The Big Heat Sink

Over the past 30 years, the Earth has absorbed unbelievably huge amounts of heat… substantially more than in prior decades. Now, scientists have discovered the whereabouts of this abnormality of excessive heat… deep in the oceans, the Earth’s Big Heat Sink! As time passes, the ocean heat sink may one day run over, in turn, prompting global warming to accelerate rapidly, very rapidly.

A little over one year ago, Dr. James Hansen, one of the world’s foremost climate scientists and former Head of NASA Goddard Institute for Space Studies, spoke at the TED Conference in Long Beach, California, explaining the heat imbalance of the planet, and he compared the imbalance to the equivalent of 400,000 Hiroshima atomic bombs per day, which is nearly impossible to fathom. But, it is how much heat the Earth absorbs per day due to global warming. According to Dr. Hansen, the imbalance means we must reduce CO2 from approximately 400 ppm, which is a new 3-million-year record, back to less than 350 ppm to restore the planet’s energy balance.

But, unfortunately, CO2 continues rising, year-by-year, and there are no signs of tapering. In fact, the rate of increase is increasing, and according to the Mauna Loa Observatory, Hawaii, as of July 9, 2013, “The concentrations of CO2 in the atmosphere are increasing at an accelerating rate from decade to decade. The latest atmospheric CO2 data is consistent with a continuation of this long-standing trend,” and confirmed by the National Oceanic & Atmospheric Administration.

Forty years ago, Hansen published an article in Science magazine that changed the world’s perception of climate, and the article was repeated on the front page of the New York Times. The article concluded that observed warming of 0.4 degrees C the prior century was consistent with the greenhouse effect on increasing CO2. And, that Earth would likely warm in the 1980s. And, that the 21st century would see shifting climate zones, creation of drought-prone regions in North America and Asia, erosion of ice sheets, rising sea levels and opening of the fabled Northwest Passage — all of these impacts have happened or are well under way.

Hansen’s paper resulted in his testifying to Congress in the 1980s. His testimony emphasized that global warming increases both extremes of the Earth’s water cycle, meaning, heat waves and droughts on the one hand directly from the warming but also, because a warmer atmosphere holds more water, rainfall will become more extreme with stronger storms and greater flooding.

Forty years later, the climate is proving him correct… on all counts.

Today, he is more concerned that ever before.

The distribution of the Heat Content of Earth

According to the Journal of Geophysical Research, the total heat content of the Earth is contained within the land and the atmosphere and the oceans. The journal publishes a graph of this relationship, which shows 90% of the Earth’s heat is contained in the oceans. The graph starts in 1960, and ever since the late 1970s, its slope looks eerily similar to Mount Everest. Starting in the late 1970s, and accelerating in the 1980s, the graph slopes steeply upwards commensurate with China discovering state capitalism and spewing enormous amounts of CO2 into the atmosphere. [To get a fuller overview, one should take into account, inter alia, per capita CO2 emissions; China is ranked relatively low. -- DV Ed.]

As well, the National Oceanic and Atmospheric Administration (“NOAA”) has numerous charts that show the oceans rapidly heating during this same time frame, and it is expected that, over time, the ocean heat will come back up, which is one reason why climatologists predict a looming climate shift to rapid acceleration of surface warming. As well, the enormous uptake of heat by the oceans may offer an additional explanation for why the Arctic Ocean is melting at such a rapid rate with a great deal of the ice melting from underneath.

Ocean Heat Measurement Techniques

The ocean temperature is measured by Argo floats of which 3,000 are deployed every 3 degrees (or 300km) in oceans around the world. Every 10 days, Argo floats descend to a target depth, typically to 2000m (1.24 miles), and over a period of six hours, the floats rise to surface while measuring temperature and salinity. Once back to surface, Argo floats relay data to satellites via an international collaboration with the Jason Satellite Altimeter Mission. (Argo is named after Jason’s ship in Greek mythology.)

The Payback –Acceleration of Global Warming

The uptake of heat by the oceans, serving as a giant ‘sink’, may account for the recent hiatus in land temperature, as its rate of warming slowed; however, the totality of the earth’s heat is what counts, not just the land temperature, and according to a research paper written by Scott Doney (Woods Hole Oceanographic Institution)1 :

The ocean slows climate change by storing excess heat and by removing CO2 from the atmosphere… [however] The ocean CO2 sink may become less effective in the future due to warming, increased vertical stratification, and altered ocean circulation, which would act to accelerate climate change.

Additionally, according to “Ocean Carbon Biogeochemistry and U.S. CLIVAR Joint Meeting Summary,”2 :

Atmospheric emissions of CO2 not only contribute to warming our climate, but are expected to have a significant impact on ocean circulation, biogeochemistry and ecosystem structure. Those changes will then feedback onto the atmosphere… resulting in a decrease the rates at which the ocean takes up and stores atmospheric carbon dioxide, further enhancing global warming.

As well, the Catalan Institute of Climate Sciences in Barcelona,3 analyzing the slow down of rising surface temperatures during the first decade of this century, concluded: Most of the excess energy was absorbed in the top 700m of the ocean at the onset of the warming pause with 65% of it confined to the tropical Pacific and Atlantic oceans. The uptake by the oceans, according to the lead scientist, resulted in hidden heat from the surface, but it is heat that may return to the atmosphere over the decade, which will stoke global warming.

The Earth’s total heat content since 1960, as illustrated by the Journal of Geophysical Research graph shows where the Earth’s heat has been going: Go to: Institute of Climate Studies, USA to see the graphic display (The heading of the graph is “Earth’s Total Heat Content Anomaly.”)

As mentioned earlier, it is interesting to note the dramatic liftoff in the chart, nearly perpendicular since 1970-80, as the world’s oceans have absorbed extraordinary levels of heat, ever since China discovered state capitalism (1970s-80s) and began powering CO2 into the atmosphere like there is no tomorrow, and as a result, there may not be a tomorrow… as we know it.

Postscript: “You come back impressed, once you’ve been up there, with how thin our little atmosphere is that supports all life here on Earth. So if we foul it up, there’s no coming back from something like that.” (John Glenn, first American, 1962, to orbit the Earth and former U.S. Senator.)

  1. U.S. Clivar Variations (U.S. Climate Variability and Predictability Research Program, Washington, DC), Summer 2012, Vol. 10, No.1 []
  2. Annalisa Bracco, Georgia Institute of Technology and Ken Johnson, Monterrey Bay Aquarium Research Institute, U.S. Clivar Variations, Summer 2012, Vol. 10, no. 1 []
  3. “Retrospective Prediction of the Global Warming Slowdown in the Past Decade,” Nature Climate Change, April 7, 2013, by Virginie Guemas, Francisco J. Doblas-Reyes, Isabel Andreu-Burillo and Muhammad Asif []

Robert Hunziker (MA, economic history, DePaul University) is a freelance writer and environmental journalist whose articles have been translated into foreign languages and appeared in over 50 journals, magazines, and sites worldwide, like Z magazine, European Project on Ocean Acidification, Ecosocialism Canada, Climate Himalaya, Counterpunch, Dissident Voice, Comite Valmy, and UK Progressive. He has been interviewed about climate change on Pacifica Radio, KPFK, FM90.7, Indymedia On Air and World View Show/UK. He can be contacted at: Read other articles by Robert.