By Dima Kulakov
So far, the world has warmed 1.1 degrees (celsius) above pre-industrial temperatures, according to the United
Nations. Most scientists believe that contemporary human activities contribute considerably to this trend.
Keeping a 1.5 degree cap on pre-industrial levels on global warming is one of the main challenges of the ongoing United Nations climate conference, COP26. That’s the lower of the two targets mentioned in the 2015 Paris Agreement on climate change.
Article 2.1.a of the Paris Agreement names a key goal as: “holding the increase in the global average temperature to well below 2 degrees above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 degrees above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change.”
A 2 degree target had been prevalent for a long time. But, in 2010, an agreement was reached to review whether there was enough new scientific evidence to suggest that the goal needed to be lowered, by 2015. A 1.5 degree goal was called for by some groups representing developing countries, including the Alliance of Small Island States (AOSIS). “That process concluded that the globally agreed goal of two degrees as a kind of guardrail was not safe … for the most vulnerable,” said Frances Fuller, the advisor on mitigation and science for AOSIS.
The Intergovernmental Panel on Climate Change (IPCC) released a special report about the difference in consequences between 1.5 degrees and 2 degrees of warming in 2018. They found that an extra half a degree of global warming may lead to more intense extremes of heat, heavy precipitation and drought and other natural disasters being more frequent.
“Every bit of global warming matters and makes things worse,” said Kirsten Zickfeld, professor of climate science at Simon Fraser University in Burnaby, B.C., one of the report’s lead authors.
In the Arctic, the melting of white ice exposes water, which is dark and absorbs more heat, making the sea ice melt faster, exposing more water, etc. Therefore Canada, especially its Arctic region, is warming faster than the world average.
“If we talk about 1.5 degree warming [on average globally], it may actually mean five degree warming in some regions of the Arctic” said Zickfeld. Scientists are concerned about tipping points that may lead to irreversible consequences, such as the melting of the Greenland or East Antarctic ice. Zickfeld said that a tipping point is estimated to be at around 2 degrees of warming. The report showed that a half-degree difference in global temperature could expose significantly more people to health, safety, and livelihoods risks. “The global population exposed to increased water shortages would be 50 percent less under 1.5 degree than 2 degree warming, Zickfeld noted.
By 2100, the sea level will be 10 centimetres higher with 2 degrees of warming than with 1.5 degrees. It will expose 10 million more people to risks of deadly flooding due to sea-level rise.
Above 1.5 degrees of warming and sea-level rise will “engulf entire nations” Fuller said. “We cannot let go of the 1.5 goal, and to go beyond that would be accepting the destruction of our communities, livelihoods, nations, culture.” More plants, animals, insects, and coral reefs will become extinct with 2 degrees of warming compared to 1.5 degrees, potentially leading to the near extinction of coral reefs. IPCC modelling shows that the world must cut emissions to 45 per cent below 2010 levels by 2030 and reach net zero by around 2050 to limit global warming to below 1.5 degrees.
Net-zero means that heat-trapping greenhouse gases would no longer be added to the atmosphere. Some greenhouse gases would still be emitted, but they would be “cancelled out” by the removal of an equivalent amount of greenhouse gases. The IPCC estimates that current countries’ pledges to cut emissions by 2030 would lead to 2.6 degree – 2.7 degree global warming, while pledges to get to net-zero, mostly by 2050, would reduce global warming to 2.2 degrees, if fully implemented.
We are behind the curve and fresh, innovative approaches and actions by governments, businesses and a new generation of leaders are desperately needed!
On a positive note, just today, Justin Trudeau announced that “Canada will put a cap on oil and gas sector emissions… [to] ensure they decrease…at a pace and scale needed to reach net-zero by 2050” at the COP26 summit, a good first step.