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Accelerating towards runaway climate change

Wind turbines and other clean-energy sources can help to bend the Keeling Curve and substantially reduce atmospheric CO2. Photo by Tyler Casey/Unsplash

“I have been impressed by the urgency of doing. Knowing is not enough, we must apply. Being willing is not enough, we must do.”

— Leonardo da Vinci (1452-1519)

Humans are one of the dominant forces on climate and the environment and climate change is arguably the defining issue of the 21st century, dubbed the Anthropocene era.

During the past year, we have endured unprecedented scorching heat waves all over the planet and the past seven years have been the hottest on record. Last year, a Canadian record temperature of 49.6 C was recorded at Lytton, B.C., the day before the town burned to the ground. The heat dome that seared the Pacific Northwest was one of the most anomalous extreme heat events ever observed.

There is a litany of climate change consequences ranging from heat waves, droughts, floods, wildfires, polar ice melt, sea-level rise, the disappearance of rivers, lakes and reservoirs, marine heat waves and the like.

Opinion: Unless we can effectively bend the Keeling Curve and substantially reduce atmospheric CO2, climate conditions will continue to deteriorate, writes David Levy. #ClimateFinance #ClimateJustice

The Earth’s energy imbalance has increased due to the greenhouse effect and considerably more radiation now enters the atmosphere than is radiated out to space.

The energy imbalance is increasing, raising the spectre of further destabilization of the ocean-atmosphere system that regulates the climate.

The most meaningful metric for monitoring climate change is CO2 concentration in the atmosphere.

Reliable measurements began at Hawaii’s Mauna Loa Observatory in 1958 and the so-called Keeling Curve has accurately tracked the inexorable increase of atmospheric CO2.

In 1958, atmospheric CO2 concentration registered 313 parts per million (ppm). As shown on the graph below, this year, CO2​​​​​​​ surpassed 420 ppm. International organization 350.org maintains that 350 ppm represents a safe concentration of CO2 in the atmosphere.

Chart Description automatically generated

This graph, known as the Keeling Curve, depicts the upward trajectory of carbon dioxide in the atmosphere as measured at the Mauna Loa Observatory by the National Oceanic and Atmospheric Administration and the Scripps Institution of Oceanography. Credit: Scripps Institution of Oceanography.

Except for the melting polar ice caps, which are several kilometres thick, it is conceivable the Earth could become essentially ice-free within a human lifetime. The consequences of a global ice and snow meltdown would fundamentally alter the planet's livability.

While the situation continues to evolve, politicians have waded in with emission targets, global confabs, pledges and strategies that collectively have had no impact whatsoever on the Keeling Curve, the bottom line for climate change mitigation.

Simply put, unless we can effectively bend the Keeling Curve and substantially reduce atmospheric CO2​​​​​​​, climate conditions will continue to deteriorate.

Separate from the Keeling Curve, the emissions curve will also need to bend, something that is yet to occur on a global basis. There is an unknown time lag between emission decreases and atmospheric CO2 reductions due to the elevated CO2 content in the oceans, which will dampen the atmospheric response.

The atmosphere doesn’t care how we collectively reduce CO2 and other greenhouse gases, whether by emission reductions or other means, but until this occurs, the climate will continue to get hotter. Mitigation attempts have tried to control emissions, but global emissions continue to rise, and few countries have lived up to their climate pledges.

The 2015 Paris Agreement established 1.5 C as a relatively safe increase to support life as we know it. To moderate the most severe impacts, global emissions need to decline to net-zero. Achievement of this target by 2050 will require a highly unlikely emissions reduction of around 40 per cent by 2030.

Social, political and technological inertia have been identified as factors that work against the achievement of the 1.5 C target and will create an overshoot situation with the magnitude and duration dependent on the actions we take in the near future. Presently, global emissions and temperatures are increasing, leaving precious little time for human response.

Canada produces around 1.5 per cent of global emissions and while it is crucial to get our house in order, until the largest emitters, including China, the U.S. and India, rein in their emissions (which collectively contribute around 50 per cent of the total), the Keeling Curve will continue to increase.

War can result when nations and human livelihoods are threatened. The most pressing war we can engage in is a war on inaction. We urgently require actions that drive down atmospheric CO2 concentrations coupled with an unprecedented societal transformation and a shift away from the pursuit of economic growth.

David Levy is an ecologist who has worked on salmon and climate change in the Fraser River.




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