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Ocean Acidification

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023). pH in these figures is provided on the total scale, which includes the contribution both from free hydrogen ions and hydrogen sulfate.

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

 

For the most up to date data, please reference the original source above.

Understanding the Time series plots

Time series plots show the changes in each indicator as a function of time, over the period 1980-present. Each plot also shows horizontal lines that indicate the median (middle) value of that indicator, as well as the 10th and 90th percentiles, each calculated for the entire period of measurement. Time series plots were only developed for datasets with at least 10 years of data. Two symbols located to the right of each plot describe how recent values of an indicator compare against the overall series. A black circle indicates whether the indicator values over the last five years are on average above the series 90th percentile (plus sign), below the 10th percentile (minus sign), or between those two values (solid circle). Beneath that an arrow reflects the trend of the indicator over the last five years; an increase or decrease greater than one standard deviation is reflected in upward or downward arrows respectively, while a change of less than one standard deviation is recorded by a left-right arrow.

Graph

Alaska - Aleutian Islands

Between 2016 and 2021 pCO2 showed a significant upward trend and was above the range of historical values.

AI PCO2

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed a significant upward trend and was above the range of historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±19 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Alaska - Beaufort Sea

Between 2016 and 2021 pCO2 showed no significant trend and was similar to historical values.

BEaufort

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed no significant trend and was similar to historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±60 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

California Current

Between 2016 and 2021 in pCO2 showed a significant increasing trend and is at the upper range of historical values.

CalCurrent

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 in pCO2 showed a significant increasing trend and is at the upper range of historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±18 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Caribbean

Between 2016 and 2021 pCO2 showed no trend but was mostly within the range of historical values.

Carib

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed no trend but was mostly within the range of historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±3 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Alaska - Eastern Bering Sea

Between 2016 and 2021 pCO2 showed a significant increasing trend and was above historical values.

EBS

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed a significant increasing trend and was above historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±16 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Alaska - Gulf of Alaska

Between 2016 and 2021 pCO2 showed no significant trend and was above historical values.

GOA

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed no significant trend and was above historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±23 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Gulf of Mexico

Between 2016 and 2021 pCO2 showed a significant increasing trend and is at the upper range of historical values.

GoM

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed a significant increasing trend and is at the upper range of historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±23 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Alaska - Northern Bering and Chukchi Seas

Between 2016 and 2021 pCO2 showed no significant trend and was above historical values.

NBC

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed no significant trend and was above historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±60 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Northeast

Between 2016 and 2021 pCO2 showed no trend and was mostly above the range of historical values to historical values.

NE

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed no trend and was mostly above the range of historical values to historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±22 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

US Pacific Islands

Between 2016 and 2021 pCO2 showed no upward trend and is at the top of the range of historical values.

PI

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed no upward trend and is at the top of the range of historical values.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Southeast

Between 2016 and 2021 pCO2 showed no significant trend but was near the top of the range of  historical values.

SE

The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates.

 

Description of Time Series: Between 2016 and 2021 pCO2 showed no significant trend but was near the top of the range of  historical values. The estimated uncertainty of the pCO2 values used to compute this regional average is ±3 μatm.

 

Description of Sea Surface pCO2:

Carbon dioxide (CO2) released from fossil fuel burning and other human activities (also known as “anthropogenic CO2”) not only accumulates in Earth’s atmosphere, but is also absorbed by seawater at the ocean surface. This process represents a double-edged sword for the planet: CO2, which has negative consequences for climate change, is removed from the atmosphere but it also contributes to the acidification of ocean waters, which can harm sea life like corals and crabs. The partial pressure of CO2 in seawater (pCO2) represents the relative amount of CO2 in the water. It is a critical metric for calculating the exchange of CO2 across the air–sea interface and for tracking the effects of anthropogenic carbon on surface ocean chemistry.

 

Data Source:

Global observations of pCO2 from automated shipboard systems that take in and analyze water while a vessel is moving are aggregated in the Surface Ocean CO2 Atlas (SOCAT; Bakker et al., 2016). These shipboard observations have been combined with data from available observational, model-based, and satellite products (e.g., sea-surface temperature, salinity, and wind speed) to create estimates of surface ocean pCO2 in U.S. Large Marine Ecosystems over multiple decades, using a technique known as machine learning (Sharp et al., in prep.). The pCO2 data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these mapped estimates. Uncertainty in pCO2 is estimated from a data-based validation of the machine-learning algorithms for each Large Marine Ecosystem, scaled by the data coverage in a given month.

Alaska - Aleutian Islands

Between 2016 and 2021 pH showed a small downward trend and was below historical values.

AI

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed a small downward trend and was below historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Beaufort Sea

Between 2016 and 2021 pH showed no significant trend and was similar to historical values.

Beaufort

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed no significant trend and was similar to historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

California Current

Between 2016 and 2021 pH showed a significant decreasing trend and is at the lower end of the range of historical values.

CCE

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed a significant decreasing trend and is at the lower end of the range of historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Caribbean

Between 2016 and 2021 pH showed no significant trend and was similar to historical values.

Carib

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed no significant trend and was similar to historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Eastern Bering Sea

Between 2016 and 2021 pH showed a significant decreasing trend and was below historical values.

EBS

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed a significant decreasing trend and was below historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Gulf of Alaska

Between 2016 and 2021 pH showed no significant trend and was below historical values.

GoA

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed no significant trend and was below historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Gulf of Mexico

Between 2016 and 2021 pH showed a significant decreasing trend and is now at the low end of the range of historical values.

GoM

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed a significant decreasing trend and is now at the low end of the range of historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Northern Bering and Chukchi Seas

Between 2016 and 2021 pH showed no significant trend and was similar to historical values.

NBC

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed no significant trend and was similar to historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Northeast

Between 2016 and 2021 pH showed no trend and was largely below the range of historical values.

NE

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed no trend and was largely below the range of historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

US Pacific Islands

Between 2016 and 2021 pH showed no significant trend but was at the low end of the range of historical values.

PI

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed no significant trend but was at the low end of the range of historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Southeast

Between 2016 and 2021 pH showed no significant trend and was below historical values.

SE

The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 pH showed no significant trend and was below historical values.

 

Description of Sea Surface pH:

Man-made (or “anthropogenic”) CO2 that is taken up by the ocean influences the chemistry of seawater, resulting in an increase in hydrogen ion concentration of the surface ocean (i.e. a decrease in surface ocean pH). pH can be viewed as a “master variable” in ocean chemistry, controlling acid-base balance in the sea. It is also a common way to quantify ocean acidification: average surface ocean pH has decreased by more than 0.1 units since the beginning of the industrial revolution (Jiang et al., 2023).

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface ocean pH across the U.S. LME’s. The pH data shown here as an ecosystem indicator of ocean acidification represent regional annual averages of these estimates. Uncertainty in pH is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Aleutian Islands

Between 2016 and 2021 Sea Surface Ωar showed a significant decreasing trend and was lower than historical values.

AI

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed a significant decreasing trend and was lower than historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Beaufort Sea

Between 2016 and 2021 Sea Surface Ωar showed no significant trend and was similar to historical values.

BEaufort

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed no significant trend and was similar to historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

California Current

Between 2016 and 2021 Sea Surface Ωar showed a downward trend but was mostly within the range of historical values.

CCE

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed a downward trend but was mostly within the range of historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Caribbean

Between 2016 and 2021 Sea Surface Ωar showed a significant decreasing trend but was mostly within the range of historical values.

Carib

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed a significant decreasing trend but was mostly within the range of historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Eastern Bering Sea

Between 2016 and 2021 Sea Surface Ωar showed no significant trend and was similar to historical values.

EBS

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed no significant trend and was similar to historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Gulf of Alaska

Between 2016 and 2021 Sea Surface Ωar showed a significant downward trend and was similar to historical values.

GoA

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed a significant downward trend and was similar to historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Gulf of Mexico

Between 2016 and 2021 Sea Surface Ωar showed a significant downward trend but was below the range of historical values.

GoM

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed a significant downward trend but was below the range of historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Alaska - Northern Bering and Chukchi Seas

Between 2016 and 2021 Sea Surface Ωar showed a significant downward trend and was similar to historical values.

NBC

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed a significant downward trend and was similar to historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Northeast

Between 2016 and 2021 Sea Surface Ωar showed no significant trend and was similar to historical values.

NE

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed no significant trend and was similar to historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

US Pacific Islands

Between 2016 and 2021 Sea Surface Ωar showed no significant trend but was at the low end of the range of historical values.

PI

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed no significant trend but was at the low end of the range of historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Southeast

Between 2016 and 2021 Sea Surface Ωar showed a significant downward trend and was below historical values.

SE

The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates.

 

Description of Time Series: Between 2016 and 2021 Sea Surface Ωar showed a significant downward trend and was below historical values.

 

Description of Sea Surface Ωar:

Many marine animals and plants build shells or other hard parts from the minerals aragonite and calcite, which are forms of the chemical compound calcium carbonate. The chemical building blocks of these minerals are calcium and carbonate ions, which are common constituents of seawater. However, one effect of ocean acidification is to reduce the carbonate ion concentration in seawater, making it more difficult for these minerals to form. The chemical expression that describes the tendency of these minerals to form at equilibrium is called the saturation state of that mineral: higher values support mineral formation, while lower values inhibit mineral formation, or even promote the dissolution of these minerals. We present here saturation-state estimates for the mineral aragonite (Ωar), which is used by many marine organisms including corals, mollusks, and some zooplankton to create hard parts. At 20°C, saturation state of the mineral calcite is about 50% higher than aragonite (Mucci, 1983)

 

Data Source:

Mapped estimates of surface-ocean pCO2 in U.S. Large Marine Ecosystems (LME’s) (Sharp et al., in prep.), based on observations from the SOCAT database, have been paired with another key ocean-carbon variable called total alkalinity (TA), estimated from salinity, temperature, and spatial information using algorithms called ESPERs (Carter et al., 2021), to calculate surface-ocean Ωar across the U.S. LME’s. The Ωar data shown here as an ecosystem indicator of ocean acidification represent regional averages of these estimates. Uncertainty in Ωar is determined by propagating pCO2 and TA uncertainties through calculations, using reasonable estimates of uncertainty in required chemical constants and ancillary variables.

Surface Ocean CO2 Atlas

SOCAT version 2022, made public in 2022, includes data from more than 10 countries. It has 37.3 million quality controlled surface ocean fCO₂ measurements from 1957 to 2022, as well as calibrated sensor data. The SOCAT data set uses IOCCP recommended formats for metadata and data reporting. SOCAT quality control is carried out by regional working groups with a global group for coordination.

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