Ocean Heat Content
Our climate has been warming for decades but where does the excess heat generated by human activity go? The ocean absorbs more than 90% of the excess heat from global warming.
Humans live in the atmosphere, not the ocean. So you can think that the ocean doing us a huge favor… but this ”favor” is not only huge, it’s deep. And the depth that excess heat reaches in our ocean is important to monitor. And ECCO is in the unique position of tracking warming over the full depth of the ocean.
Download ECCO Ocean Heat Content data (JSON file)Our climate has been warming for decades but where does the excess heat generated by human activity go? The ocean absorbs more than 90% of the excess heat from global warming.
Humans live in the atmosphere, not the ocean. So you can think that the ocean doing us a huge favor… but this ”favor” is not only huge, it’s deep. And the depth that excess heat reaches in our ocean is important to monitor. And ECCO is in the unique position of tracking warming over the full depth of the ocean.
Download ECCO Ocean Heat Content data (JSON file)
Upper 200 Meters
But let’s start at the top, with a map showing ocean heat trend over the past 30 years in the upper 200 meters (656 feet) of the ocean. Red colors show where warming occurred over these decades. These coincide with areas where destructive hurricanes and cyclones are fueled by warm ocean water.
According to data from the U.S. Environmental Protection Agency, North Atlantic hurricane intensity had ”risen noticeably” from 2000 to 2020. ECCO reveals that ocean heat content in upper 200 meters also rose over that time period (orange line). Moreover, the heat content trend accelerated further from 2017 through 2022 (red line). This latest increase in the ocean heat content trend is an active area of investigation for ECCO researchers.
Upper 700 Meters
Now let’s dive deeper. This time-series graph compares the last 30 years of ocean heat trends between the upper 200 meters and the upper 700 meters, which is not quite half of a mile. It’s clear that ocean warming is happening at both depths and has accelerated further over the last five years.
So far we’ve shared ocean heat trends beginning in 1992. However, the trend has been calculated even further back – to 1955 – by NOAA’s National Centers for Environmental Information. The red line from ECCO agrees well with NOAA’s recent data (black line with gray error bars) and thus independently confirms their findings.
Why is NOAA's trend longer? They use the long, yet sparse record of data from in-water instruments that sample the upper ocean. ECCO augments in-water data with a wealth of observations from ocean-observing satellites that began in 1992. ECCO combines all of these observations with physical models. This yields an estimate of the time-varying ocean that is consistent with observed ocean conditions and ocean physics, which is more complete and better than either alone.
Check out the “How Deep is Your Heat?” StoryMap
Why is NOAA's trend longer? They use the long, yet sparse record of data from in-water instruments that sample the upper ocean. ECCO augments in-water data with a wealth of observations from ocean-observing satellites that began in 1992. ECCO combines all of these observations with physical models. This yields an estimate of the time-varying ocean that is consistent with observed ocean conditions and ocean physics, which is more complete and better than either alone.
Check out the “How Deep is Your Heat?” StoryMap
Full Ocean Depth
Now let’s get to the bottom of it... ECCO’s unique contribution of calculating heat content to the full depth of our ocean. It is clear that our ocean is warming at all depths. Think about it: deeper ocean depths correspond to higher volumes of seawater. Thus warming in the full depth of the ocean potentially impacts 321,003,271 cubic miles of seawater!
The trend in warming of the full ocean was fairly steady between 1992 and 2017 as shown by the orange line. Similar to the ECCO results from the top 200m meters shown earlier, the full ocean heat content trend accelerated sharply from 2017 through 2022 (red line). This latest increase in the ocean heat content trend is an active area of investigation for ECCO researchers.
