Ignoring a Warming Sea
Terry H. Schwadron
Jan. 12, 2019
The world best thermometer — its oceans — are warming faster than predicted, again hastening the effects of Climate Change and the debate about what to do about it.
New analysis published in the journal Sciencesuggests that oceans are heating up 40% faster on average than a United Nations student found even five years ago, and that yearly, the temperatures are going up steadily.
The analysis found that this warming record is contributing to increases in rainfall intensity, rising sea levels, the destruction of coral reefs, declining ocean oxygen levels, and declines in ice sheets; glaciers; and ice caps in the polar regions. Recent estimates of observed warming resemble those seen in models, indicating that models reliably project changes in what is called ocean heat content.
Climate change from human activities mainly results from the energy imbalance in Earth’s climate system caused by rising concentrations of heat-trapping gases., said Science, adding that about 93% of the energy imbalance accumulates in the ocean as increased ocean heat content (OHC). The ocean record of this imbalance is much less affected by internal variability and is thus better suited for detecting and attributing human influences than more commonly used surface temperature records.
The New York Timesbuilt on the Science report, saying that the surging water temperatures are already killing off marine ecosystems, raising sea levels and making hurricanes more destructive. As the oceans continue to heat up, those effects will become more catastrophic, scientists told The Times.
Rainier, more powerful storms like Hurricane Harvey in 2017 and Hurricane Florence in 2018 will become more common, and coastlines around the world will flood more frequently. Coral reefs, whose fish populations are sources of food for hundreds of millions of people, will come under increasing stress; a fifth of all corals have already died in the past three years.
People in tropical areas, who rely heavily on fish for protein, could be hard hit, said Kathryn Matthews, deputy chief scientist for the conservation group Oceana. “The actual ability of the warm oceans to produce food is much lower, so that means they’re going to be more quickly approaching food insecurity,” she said.
Oceans are one of the most important areas of research for climate scientists. Average ocean temperatures are also a consistent way to track the effects of greenhouse gas emissions because they are not influenced much by short-term weather patterns.
The Times noted that an authoritative United Nations report, issued in 2014 by the Intergovernmental Panel on Climate Change, presented five different estimates of ocean heat, but they all showed less warming than the levels projected by computer climate models — suggesting that either the ocean heat measurements or the climate models have been inaccurate.
Since the early 2000s, scientists have measured ocean heat using a network of drifting floats called Argo, named after Jason’s ship in Greek mythology. The floats measure the temperature and saltiness of the upper 6,500 feet of the ocean and upload the data via satellites.
Before Argo, researchers had relied on temperature sensors that ships lowered into the ocean with copper wire, Science explained. The wire transferred data from the sensor to the ship for recording until the wire broke and the sensor drifted away. That method was subject to uncertainties, particularly around the accuracy of the depth at which the measurement was taken. Those uncertainties hamper today’s scientists as they stitch together temperature data.
Waters closest to the surface have heated up the most, and that warming has accelerated over the past two decades, said Science. As the oceans heat up, sea levels rise because warmer water takes up more space than colder water. In fact, most of the sea level rise observed to date is because of this warming effect, not melting ice caps.
All this brings up the obvious: What are we going to do about it?
The United States, which has pulled away from any international agreement on Climate Change controls, in fact has been increasing in carbon emissions, despite any non-government attempts to be more energy efficient. Recent articles have noted a general rise in the number and variety of manufacturing plants in the United States to help explain rising land temperatures. Absent global action to reduce carbon emissions, the Science said, the warming alone would cause sea levels to rise by about a foot by 2100, and the ice caps would contribute more.
That, in turn, will have an effect on marine life , driving species into new grounds, driving national conflicts over fishing rights and other trade areas.
Rather than declaring a national emergency about a border Wall, perhaps the president should be looking to Climate Change as the source of a bigger and actual emergency.
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