Główne pojęcia
Climate model projections underestimate the increase in the longest annual dry spells globally by 42-44% on average compared to current high-end scenarios.
Streszczenie
The article presents a new emergent constraint (EC) approach to reduce the uncertainty in climate model projections of a core drought indicator, the longest annual dry spell (LAD). By constraining the model projections with observations, the study finds that the increase in LAD will be significantly greater than what is currently projected under 'mid-range' or 'high-end' future forcing scenarios.
The key insights are:
- The EC-corrected projections reveal that the increase in LAD will be 42-44% greater on average than currently indicated by climate models.
- By the end of this century, the global mean land-only LAD could be 10 days longer than currently expected.
- The study identifies global regions where historical LAD biases in climate models affect the magnitude of projected LAD increases, and explores the role of land-atmosphere feedbacks in these biases.
- The findings suggest that societies and ecosystems in certain regions may face higher and earlier-than-expected drought risks compared to current projections.
- The study points to potential mechanisms underlying the biases in the current generation of climate models, which could help improve future projections of drought extremes.
Statystyki
The increase in the longest annual dry spell (LAD) will be 42-44% greater on average than currently projected by climate models.
By the end of this century, the global mean land-only LAD could be 10 days longer than currently expected.
Cytaty
"Climate models indicate that dry extremes will be exacerbated in many regions of the world1,2. However, confidence in the magnitude and timing of these projected changes remains low3,4, leaving societies largely unprepared5,6."
"Our EC-corrected projections reveal that the increase in LAD will be 42–44% greater, on average, than 'mid-range' or 'high-end' future forcing scenarios currently indicate."