Every year, the World Meteorological Organization, or WMO, tracks a list of key climate indicators – including the amount of carbon dioxide in the atmosphere and the Earth’s temperature – to assess how global warming is progressing. In their latest report, released last Sunday, the authors decided to include a new dimension: the imbalance of Earth’s power.
“Climate change is often discussed in terms of global warming,” John Kennedy, the report’s lead author and science coordinator, said in an email to Grist. But annual changes in air temperature, caused by El Niño and La Niña weather patterns, can “mask the long-term trend” of global warming, Kennedy said.
However, with the introduction of this new important symbol, the authors of the WMO intended to clarify the basic processes of global warming, and to represent them easily. Earth’s energy imbalance, or EEI, is a simple concept: It’s the difference between how much energy the earth takes from the sun and how much energy is returned to space. Put even more simply, energy imbalance, Kennedy said, “is basically what climate change is all about.”
“As long as the energy imbalance persists, the Earth will continue to warm, the ice will continue to melt, and the sea level will continue to rise,” he added.
In terms of numbers, the WMO’s findings should come as no surprise to anyone following the climate crisis. Because of the greenhouse gas effect, the Earth has been holding onto more energy, mostly as heat, since the 1960s. And every year for the past nine years, that rate has set a new record.
In addition, the report shows where most of that heat is going on Earth. The oceans, the WMO reports, absorb 91 percent of the excess energy hanging over the Earth’s climate. Kennedy said that, as an important indicator of global warming, the EEI provides a context that helps to understand all the other indicators tracked by the organization, such as sea level rise and ice melting.
These rising sea temperatures also have significant effects on food webs in many ways. Warming oceans mean coral bleaching, habitat loss, and reduced fish yields. Rising sea levels also cause coastal erosion, which can damage the lives of people who work in fisheries – and cause problems for people and other animals who depend on them for food. As the ice melts, the resulting floods can also disrupt agricultural production.
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Jennifer Jacquet, a professor of environmental science and policy at the University of Miami, said she “very much appreciated” the WMO’s efforts to fix the climate problem – and emphasize the link between the oceans and global warming. Oceans are often referred to as carbon sinks – but Jacquet, who was not involved in the WMO report, prefers to refer to them as carbon sponges, as a way of showing that this environment has saturation points. Because the oceans are taking up so much carbon, he fears they are “cheating” how far climate change has progressed this century – that is, how much more heat has been absorbed than is reflected in the atmosphere.
Jacquet also said the question of how ocean warming affects food security is complex. For example, ocean heat waves can affect farmed fish a lot, because these fish cannot move freely. In Chile in 2016, a fish farmer noticed that Atlantic salmon were dying at a high rate after the algae bloom, because they couldn’t escape it.
Jacquet argues that farmed fish often end up serving high-income earners, not those in need. But as the oceans warm, wild fish are moving closer to the North Poles and South Poles where the relatively cooler water carries more oxygen. The practice has a negative impact on the lives of fishermen near the equator, Jacquet said, and could increase food insecurity.
“The oceans are reaching the limit of what they can do to help stop anthropogenic changes,” he said, adding that scientists and science communicators should try “any way we can to make that truth known.”
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