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Abstract The boreal summer climate is of significant societal importance and is trending toward increased risks of extreme climate events such as heatwaves. The summer North Atlantic Oscillation, as the primary mode of atmospheric variability in the northern hemisphere, has been long considered lacking predictability on seasonal time scales. Here we show that the summer North Atlantic Oscillation is predictable with a 2‐month lead for the recent decades. The primary predictor is the March North Atlantic jet strength, which is correlated with the summer North Atlantic Oscillation index at a correlation coefficient of 0.66 over 1979–2018. Spring stratosphere‐troposphere coupling plays a critical role in this extended predictability from spring to summer, in contrast to the common knowledge that this dynamical coupling is relatively inactive outside the winter season. These results may bring sound prospects for summer seasonal prediction of boreal climate that benefits the energy and public health sectors.
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Climate-driven changes in the predictability of seasonal precipitation
Abstract Climate-driven changes in precipitation amounts and their seasonal variability are expected in many continental-scale regions during the remainder of the 21st century. However, much less is known about future changes in the predictability of seasonal precipitation, an important earth system property relevant for climate adaptation. Here, on the basis of CMIP6 models that capture the present-day teleconnections between seasonal precipitation and previous-season sea surface temperature (SST), we show that climate change is expected to alter the SST-precipitation relationships and thus our ability to predict seasonal precipitation by 2100. Specifically, in the tropics, seasonal precipitation predictability from SSTs is projected to increase throughout the year, except the northern Amazonia during boreal winter. Concurrently, in the extra-tropics predictability is likely to increase in central Asia during boreal spring and winter. The altered predictability, together with enhanced interannual variability of seasonal precipitation, poses new opportunities and challenges for regional water management.
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- PAR ID:
- 10426646
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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