Much of a recent BBC radio segment focused on the short-term reduction in the rate of atmospheric warming, and reinforced some misconceptions about climate science. Mainstream scientists are not suggesting that global warming has stalled. And mainstream scientists are not stumped by the short-term atmospheric warming rate change.
The following is a guest post by Climate Nexus. Full text in PDF here.
Global Warming Misconceptions on BBC Radio
The recent BBC radio segment on global warming correctly concludes that we are already experiencing the impacts of global warming, and scientists agree we need to act now to avert much worse impacts in the future. However, much of the piece focused on the short-term reduction in the rate of atmospheric warming, and reinforces several misconceptions. In fact:
- Variation in the rate of warming in air temperatures, with slower warming followed by faster warming, has been a regular pattern over the years and has long been expected by science.
- Ocean temperatures are soaring without rate reduction.
- Acting now is the best strategy regardless of the exact rate of warming.
The claim:
The BBC segment stated that the scientific establishment “agrees that global warming seems to have stalled” and “mainstream scientists have been puzzled by the standstill in warming.” It also suggested that a doubling of CO2 may result in a temperature increase of only 1.5 ºC (climate sensitivity) and this is an amount that “we could probably live with.”
The details:
- Mainstream scientists are not suggesting that global warming has stalled. They have noted a short-term decline in the rate of atmospheric warming, one that is consistent with predictions as well as with the overall stair-step pattern of atmospheric warming over the years, in which warming regularly slows down for a few years only to speed up again. Furthermore, mainstream scientists have found that ocean warming has soared and thus “global” warming cannot be said to have stalled.
- Mainstream scientists are not stumped by the atmospheric warming rate change. Several factors have been identified as contributing to the trend, including the temporary diversion of warming to the ocean, as well as increases in short-lived but cooling aerosol particles emitted in industrial pollution.
- Scientists are still working on refining estimates of our exact climate sensitivity, but the recent study showing a sensitivity of only 1.5 ºC is a wide outlier compared to the many other studies that have been conducted on the question. The study was conducted by Nic Lewis, a longtime vocal skeptic. And if the world continues emissions as usual, we are projected to go far beyond the levels that would spur 1.5 C change, with subsequent damage that few would expect society to easily “live with.” For a fuller understanding of climate sensitivity, see this FAQ.
It is an important scientific undertaking to refine our knowledge of different factors impacting the rate of atmospheric warming. But this discussion should not obscure the underlying fact that warming will continue as long as we continue to emit greenhouse gases, and will be dangerous for the well-being of humans around the world.
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Also see:
UK Guardian: Global warming has not stalled, insists world’s best-known climate scientist
Carbon Brief: A double dose of climate science from the BBC’s Today Programme