euronews.com
Climate Change Triples Frequency of Extreme Weather-Causing Planetary Waves
A new study published in PNAS reveals that climate change has tripled the frequency of atmospheric planetary waves causing extreme summer weather in the last 75 years, from roughly one event per summer in the 1950s to about three now; this is linked to events like the 2021 Pacific Northwest heatwave and the 2003 European heatwave, and explains why computer models underestimate the surge in extreme weather.
- How has climate change amplified the frequency of atmospheric planetary wave events, and what are the direct consequences for extreme summer weather?
- A new study reveals that climate change has tripled the frequency of atmospheric planetary wave events linked to extreme summer weather over the past 75 years. This surge in events, from roughly one per summer in the 1950s to approximately three per summer currently, is implicated in recent devastating weather events such as the 2021 Pacific Northwest heatwave and the 2003 European heatwave. These waves, when amplified, become "stuck", leading to prolonged periods of extreme heat, drought, or rainfall.
- What is the specific mechanism by which Arctic warming contributes to the increased frequency of amplified planetary waves and subsequent extreme weather events?
- The increased frequency of these amplified planetary waves is directly attributed to human-caused climate change, specifically the Arctic warming at a rate three to four times faster than the global average. This reduced temperature difference between the tropics and the Arctic weakens the jet stream, making it more susceptible to becoming locked in place. This mechanism, previously underrepresented in climate models, helps explain why the increase in extreme weather events has surpassed model predictions.
- How can the findings of this study improve climate models and lead to more accurate predictions of future extreme summer weather events, especially considering the role of El Niño?
- This research highlights a critical gap in current climate models' ability to accurately predict the frequency and intensity of extreme summer weather events. The failure to account for the amplified planetary wave mechanism leads to underestimation of future risks. The increased frequency of these events, exacerbated by El Niño events like the one in 2024, necessitates refining climate models to incorporate this crucial factor for more accurate and impactful forecasting of future extreme weather.
Cognitive Concepts
Framing Bias
The article presents a clear and consistent narrative emphasizing the link between climate change and the increased frequency of extreme weather events. The headline and opening paragraph effectively set the stage for this focus. While the article acknowledges natural variability (El Niño), the overall framing strongly emphasizes the role of human activity.
Language Bias
The language used is largely neutral and objective, relying on scientific terminology and direct quotes from experts. Terms like "killer heatwaves" are used, but given the context (describing deadly events), they don't seem unduly sensationalized.
Bias by Omission
The article focuses primarily on the increased frequency of planetary waves and their connection to extreme weather events. While it mentions the role of El Niño, a more in-depth exploration of other contributing factors to extreme weather (e.g., land use changes, deforestation) could provide a more comprehensive understanding. The article also doesn't delve into the socio-economic impacts of these extreme weather events, which could be a significant omission.
Gender Bias
The article features multiple male climate scientists (Mann, Francis). While this doesn't inherently indicate bias, seeking out and including diverse voices, including female scientists, would enhance the article's inclusivity.
Sustainable Development Goals
The article highlights that climate change, driven by human activities, has tripled the frequency of atmospheric wave events leading to extreme weather such as heatwaves, droughts, and floods. This directly impacts climate action goals by exacerbating the effects of climate change and making it harder to mitigate its impacts. The increased frequency of these events is a direct consequence of human-caused climate change, primarily from burning fossil fuels, and the amplified warming in the Arctic.