Posts
Ocean Heat
9
November, 2015
Sea
Surface Temperatures
Sea surface temperatures were as high as 15.8°C or 60.4°F near Svalbard on November 7, 2015, a 13.7°C or 24.7°F anomaly. Let this sink in for a moment. The water used to be close to freezing point near Svalbard around this time of year, and the water now is warmer by as much as 13.7°C or 24.7°F.
Sea surface temperatures were as high as 15.8°C or 60.4°F near Svalbard on November 7, 2015, a 13.7°C or 24.7°F anomaly. Let this sink in for a moment. The water used to be close to freezing point near Svalbard around this time of year, and the water now is warmer by as much as 13.7°C or 24.7°F.
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Above
image further shows that sea surface temperature anomalies as high
as 6.7°C or 12.1°F were recorded on November 7, 2015, off the
coast of North America, while anomalies as high as 6°C or 10.9°F
were recorded in the Bering Strait.
NOAA analysis shows that the global sea surface in September 2015 was the warmest on record, at 0.81°C (1.46°F) above the 20th century average of 16.2°C (61.1°F). On the Northern Hemisphere, the anomaly was 1.07°C (1.93°F).
NOAA analysis shows that the global sea surface in September 2015 was the warmest on record, at 0.81°C (1.46°F) above the 20th century average of 16.2°C (61.1°F). On the Northern Hemisphere, the anomaly was 1.07°C (1.93°F).
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How did temperatures get so high near Svalbard? The answer is that ocean currents are moving warm water from the Atlantic Ocean into the Arctic Ocean. The ocean is warmer underneath the sea surface and at that location near Svalbard warm water from below the surface emerges at the surface.
Ocean Heat
The oceans are warming up rapidly, especially the waters below the sea surface. Of all the excess heat resulting from people's emissions, 93.4% goes into oceans. Accordingly, the temperature of oceans has risen substantially over the years and - without action - the situation only looks set to get worse.
NOAA's ocean heat content figures for 0-2000 m are very worrying, as illustrated by the image below.
The image below was created with data for January through to March, while adding non-linear trendlines for ocean heat at depths of 0-700 m and 0-2000 m.
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While
growth of ocean heat content for 0-700 m appear to follow a
polynomial trend, growth of ocean heat content for 0-2000 m appears
to be rising even more strongly, following an exponential
trend.
The danger is that, as ocean heat continues to grow, ocean currents will keep carrying ever warmer water from the Atlantic and Pacific Oceans into the Arctic Ocean.
Merely watching temperatures at the surface of the ocean may underestimate the warming that is taking place below the sea surface. At the sea surface, evaporation takes place that cools the water. Furthermore, melting of sea ice and glaciers will make that a layer of cold freshwater spreads at the surface, preventing much transfer of heat from the ocean to the atmosphere, as discussed at this earlier post. The blue-colored areas on the Northern Hemisphere on the top image are partly the result of this meltwater. There is another reason why these areas are relatively cool, i.e. sulfates, as further discussed in the section below.
Sulfate
Particulates, in particular sulfate, can provide short-term cooling of the sea surface. Large amounts of sulfate are emitted from industrial areas in the east of North America and in East Asia. On the Northern Hemisphere, the Coriolis effect makes that such emissions will typically reach areas over the nearby ocean to the east of such industrial areas, resulting in the sea surface there being cooled substantially, until the particulates have fallen out of the sky. Since the sulfate is emitted on an ongoing basis, the cooling effect continues without much interruption.
The danger is that, as ocean heat continues to grow, ocean currents will keep carrying ever warmer water from the Atlantic and Pacific Oceans into the Arctic Ocean.
Merely watching temperatures at the surface of the ocean may underestimate the warming that is taking place below the sea surface. At the sea surface, evaporation takes place that cools the water. Furthermore, melting of sea ice and glaciers will make that a layer of cold freshwater spreads at the surface, preventing much transfer of heat from the ocean to the atmosphere, as discussed at this earlier post. The blue-colored areas on the Northern Hemisphere on the top image are partly the result of this meltwater. There is another reason why these areas are relatively cool, i.e. sulfates, as further discussed in the section below.
Sulfate
Particulates, in particular sulfate, can provide short-term cooling of the sea surface. Large amounts of sulfate are emitted from industrial areas in the east of North America and in East Asia. On the Northern Hemisphere, the Coriolis effect makes that such emissions will typically reach areas over the nearby ocean to the east of such industrial areas, resulting in the sea surface there being cooled substantially, until the particulates have fallen out of the sky. Since the sulfate is emitted on an ongoing basis, the cooling effect continues without much interruption.
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This
sulfate has a cooling effect on areas of the sea surface where ocean
currents are moving warm water toward the Arctic Ocean. Because the
sea surface gets colder, there is less evaporation, and thus less
heat transfer from the ocean to the atmosphere during the time it
takes for the water to reach the Arctic Ocean. As a result, water
below the sea surface remains warmer as it moves toward the Arctic
Ocean.
The Threat
Ocean heat will increasingly threaten to reach the seafloor and unleash huge methane eruptions from destabilizing clathrates. Such large methane eruptions will then warm the atmosphere at first in hotspots over the Arctic and eventually around the globe, while also causing huge temperature swings and extreme weather events, contributing to increasing depletion of fresh water and food supply, as further illustrated by the image below, from an earlier post.
The Threat
Ocean heat will increasingly threaten to reach the seafloor and unleash huge methane eruptions from destabilizing clathrates. Such large methane eruptions will then warm the atmosphere at first in hotspots over the Arctic and eventually around the globe, while also causing huge temperature swings and extreme weather events, contributing to increasing depletion of fresh water and food supply, as further illustrated by the image below, from an earlier post.
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Climate
Plan
The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan.
The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan.
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