**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.

#### Alaska - Eastern Bering Sea

This time series shows the average integrated degree day value for Alaska’s Eastern Bering Sea region. During the last five years there has been a downward trend.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Alaska’s Eastern Bering Sea region. During the last five years there has been a downward trend.

**Indicator Source Information:**

The marine heatwave data shown here are calculated by NOAA’s National Centers for Environmental Information using Optimum Interpolation Sea Surface Temperature (OISST) data. The NOAA 1/4° OISST is a long term Climate Data Record that incorporates observations from different platforms (satellites, ships, buoys and Argo floats) into a regular global grid. The dataset is interpolated to fill gaps on the grid and create a spatially complete map of sea surface temperature. Satellite and ship observations are referenced to buoys to compensate for platform differences and sensor biases.

**Data Background and Caveats:**

Heatwave metrics are calculated using OISST, a product that uses some forms of interpolation to fill data gaps. Heatwaves are defined by Hobday et al., 2016 as distinct events where SST anomaly reaches the 90th percentile in a pixel for at least 5 days, separated out by 3 or more days.

#### Alaska - Gulf of Alaska

During the last five years there has been an increasing trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Alaska’s Gulf of Alaska region. During the last five years there has been an increasing trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

The marine heatwave data shown here are calculated by NOAA’s National Centers for Environmental Information using Optimum Interpolation Sea Surface Temperature (OISST) data. The NOAA 1/4° OISST is a long term Climate Data Record that incorporates observations from different platforms (satellites, ships, buoys and Argo floats) into a regular global grid. The dataset is interpolated to fill gaps on the grid and create a spatially complete map of sea surface temperature. Satellite and ship observations are referenced to buoys to compensate for platform differences and sensor biases.

**Data Background and Caveats:**

Heatwave metrics are calculated using OISST, a product that uses some forms of interpolation to fill data gaps. Heatwaves are defined by Hobday et al., 2016 as distinct events where SST anomaly reaches the 90th percentile in a pixel for at least 5 days, separated out by 3 or more days.

#### Alaska - Chukchi Sea

During the last five years there has been a significant downward trend but the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Alaska’s Chukchi Sea region. During the last five years there has been a significant downward trend but the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

The marine heatwave data shown here are calculated by NOAA’s National Centers for Environmental Information using Optimum Interpolation Sea Surface Temperature (OISST) data. The NOAA 1/4° OISST is a long term Climate Data Record that incorporates observations from different platforms (satellites, ships, buoys and Argo floats) into a regular global grid. The dataset is interpolated to fill gaps on the grid and create a spatially complete map of sea surface temperature. Satellite and ship observations are referenced to buoys to compensate for platform differences and sensor biases.

**Data Background and Caveats:**

Heatwave metrics are calculated using OISST, a product that uses some forms of interpolation to fill data gaps. Heatwaves are defined by Hobday et al., 2016 as distinct events where SST anomaly reaches the 90th percentile in a pixel for at least 5 days, separated out by 3 or more days.

#### Gulf of Mexico

During the last five years there has been no trend and the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the Gulf of Mexico region. During the last five years there has been no trend and the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Northeast

During the last five years there has been an increasing trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the Northeast region. During the last five years there has been an increasing trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Southeast

During the last five years there has been no trend but the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the Southeast region. During the last five years there has been no trend but the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### California Current

During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the California Current region. During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### American Samoa

During the last five years there has been a significant downward trend but the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for American Samoa. During the last five years there has been a significant downward trend but the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Caribbean

During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the Caribbean region. During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Guam & the Northern Mariana Islands

During the last five years there has been a significant increasing trend but the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the Guam and CNMI region. During the last five years there has been a significant increasing trend but the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Hawaiian Insular LME

During the last five years there has been no trend but the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the Hawaiian Insular LME region. During the last five years there has been no trend but the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Howland & Baker Islands

During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Howland and Baker Islands. During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Jarvis Island

During the last five years there has been a significant decreasing trend and the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Jarvis Island. During the last five years there has been a significant decreasing trend and the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Johnson Atoll

During the last five years there has been a significant decreasing trend but the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Johnson Atoll. During the last five years there has been a significant decreasing trend but the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Kingman Reef & Palmyra Atoll

During the last five years there has been a significant decreasing trend and the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Kingman Reef and Palmyra Atoll region. During the last five years there has been a significant decreasing trend and the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Wake Island

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the Wake Island region. During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Great Lakes

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for the Great Lakes region. During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Ontario

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Lake Ontario. During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Erie

During the last five years there has been no significant trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Lake Erie. During the last five years there has been no significant trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Huron

During the last five years there has been no trend but the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Lake Huron. During the last five years there has been no trend but the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Michigan

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Lake Michigan. During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Superior

During the last five years there has been a significant increasing trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Lake Superior. During the last five years there has been a significant increasing trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Alaska - Beaufort Sea

During the last five years there has been a significant downward trend but the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate c**umulative annual heatwave intensity and duration in a region in degree-days*

**Description of Time Series: **This time series shows the average integrated degree day value for Alaska’s Beaufort region. During the last five years there has been a significant downward trend but the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Alaska - Eastern Bering Sea

During the last five years heatwave coverage has had no trend, and the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Alaska’s Eastern Bering Sea Region. During the last five years heatwave coverage has had no trend, and the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

Heatwave metrics are calculated using OISST, a product that uses some forms of interpolation to fill data gaps. Heatwaves are defined by Hobday et al., 2016 as distinct events where SST anomaly reaches the 90th percentile in a pixel for at least 5 days, separated out by 3 or more days

#### Alaska - Gulf of Alaska

During the last five years there has been no trend and the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series:** This time series shows the monthly heatwave spatial coverage for Alaska’s Gulf of Alaska Region. During the last five years there has been no trend and the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

Heatwave metrics are calculated using OISST, a product that uses some forms of interpolation to fill data gaps. Heatwaves are defined by Hobday et al., 2016 as distinct events where SST anomaly reaches the 90th percentile in a pixel for at least 5 days, separated out by 3 or more days

#### Alaska - Chukchi Sea

During the last five years there has been a significant downward trend and the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Alaska’s Chukchi Sea Region. During the last five years there has been a significant downward trend and the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

Heatwave metrics are calculated using OISST, a product that uses some forms of interpolation to fill data gaps. Heatwaves are defined by Hobday et al., 2016 as distinct events where SST anomaly reaches the 90th percentile in a pixel for at least 5 days, separated out by 3 or more days

#### Gulf of Mexico

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **

This time series shows the monthly heatwave spatial coverage for the Gulf of Mexico Region. During the last five years there has been no trend and the five-year average is between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Northeast

During the last five years marine heatwave coverage has trended upward and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for the Northeast Region. During the last five years marine heatwave coverage has trended upward and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Southeast

During the last five years there has been no significant trend and the five-year mean is above the 90th percentile of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for the Southeast Region. During the last five years there has been no significant trend and the five-year mean is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### California Current

During the last five years there has been no trend and the five-year mean is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for the California Current Region. During the last five years there has been no trend and the five-year mean is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Caribbean

During the last five years there has been no trend and the five-year mean is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **

This time series shows the monthly heatwave spatial coverage for the Caribbean Region. During the last five years there has been no trend and the five-year mean is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### American Samoa

During the last five years there has been a significant downward trend but the five-year mean is between the 10th and the 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **

This time series shows the monthly heatwave spatial coverage for the American Samoa Region. During the last five years there has been a significant downward trend but the five-year mean is between the 10th and the 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Guam + CNMI

During the last five years heatwave coverage has had a significant upward trend and the five-year mean is higher than the 90th percentile of all observations in this record.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Guam and CNMI Region. During the last five years heatwave coverage has had a significant upward trend and the five-year mean is higher than the 90th percentile of all observations in this record.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Hawaiian Insular LME

During the last five years heatwave coverage has no trend but the five-year mean is higher than the 90th percentile of all observations in this record.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for the Hawaiian Insular LME Region. During the last five years heatwave coverage has no trend but the five-year mean is higher than the 90th percentile of all observations in this record.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Howland & Baker Islands

During the last five years there has been a significant downward trend and the five-year mean is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Howland and Baker Islands. During the last five years there has been a significant downward trend and the five-year mean is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Jarvis Island

During the last five years there has been no significant trend and the five-year mean is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Jarvis Island. During the last five years there has been no significant trend and the five-year mean is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Johnson Atoll

During the last five years there has been a significant downward trend and the five-year mean is between the 10th and 90th percentiles of all observations in this record.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Johnson Atoll. During the last five years there has been a significant downward trend and the five-year mean is between the 10th and 90th percentiles of all observations in this record.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Kingman Reef & Palmyra Atoll

During the last five years there has been a significant downward trend and the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Kingman Reef and Palmyra Atoll. During the last five years there has been a significant downward trend and the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Wake Island

During the last five years there has been no trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Wake Island. During the last five years there has been no trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Great Lakes

During the last five years there has been no significant trend and values have remained between the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for the Great Lakes Region. During the last five years there has been no significant trend and values have remained between the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Ontario

During the last five years there has been a significant upward trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Lake Ontario. During the last five years there has been a significant upward trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Erie

During the last five years there has been no trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Lake Erie. During the last five years there has been no trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Huron

During the last five years there has been a significant upward trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Lake Huron. During the last five years there has been a significant upward trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Michigan

During the last five years heatwave coverage had no significant trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Lake Michigan. During the last five years heatwave coverage had no significant trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Lake Superior

During the last five years heatwave coverage has shown no significant trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **

This time series shows the monthly heatwave spatial coverage for Lake Superior. During the last five years heatwave coverage has shown no significant trend and the five-year average is within the 10th and 90th percentiles of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

#### Alaska - Beaufort Sea

During the last five years heatwave coverage has had no trend, and the five-year average is above the 90th percentile of all observed data in the time series.

*Values indicate monthly percent of an LME area affected by heatwave*

**Description of Time Series: **This time series shows the monthly heatwave spatial coverage for Alaska’s Beaufort Sea Region. During the last five years heatwave coverage has had no trend, and the five-year average is above the 90th percentile of all observed data in the time series.

**Indicator Source Information:**

**Data Background and Caveats:**

Close

## Additional Resources

#### NOAA PSL Marine Heatwaves

Scientists at PSL are working to characterize marine heatwaves, understand how they form and dissipate, and predict them in advance. On this page, we will provide current ocean maps, forecasts of heatwaves, interactive tools for users to explore ocean heatwaves themselves, links to research results and to webpages at other institutions.

#### The California Current Marine Heatwave Tracker - Blobtracker

Developed by oceanographers from NOAA Fisheries’ Southwest Fisheries Science Center as an experimental tool for natural resource managers, the California Current MHW Tracker is a program designed to understand, describe, and provide a historical context for the 2014-16 blob.2 It also produces a range of indices that could help forecast or predict future MHWs expected to impact our coast.