Details

Autor(en) / Beteiligte

• Adam, Ori
• Shourky Wolff, Maya
• Garfinkel, Chaim I.
• Byrne, Michael P.

Titel

Increased Uncertainty in Projections of Precipitation and Evaporation Due To Wet‐Get‐Wetter/Dry‐Get‐Drier Biases

Ist Teil von

• Geophysical research letters, 2023-12, Vol.50 (24), p.n/a

Ort / Verlag

Washington: John Wiley & Sons, Inc

Erscheinungsjahr

2023

Link zum Volltext

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• A key implication of the well known wet‐get‐wetter/dry‐get‐drier (WGW) scaling is that model biases in the representation of precipitation and evaporation in the present climate lead to spurious projected changes under global warming. Here we estimate the extent of such spurious changes in projections by 60 models participating in phases 5 and 6 of the Coupled Model Intercomparison Project. Utilizing known thermodynamic constraints on evaporation, we show that the WGW scaling can be applied to precipitation and evaporation separately (specific WGW scaling), which we use to correct for spurious projected changes in precipitation and evaporation over tropical oceans. The spurious changes in precipitation can be of comparable amplitude to projected changes, but are generally small for evaporation. The spurious changes may increase the uncertainty in projections of tropical precipitation and evaporation by up to 30% and 15% respectively. Plain Language Summary It is well established that if winds are assumed unchanged, the response of the hydrological cycle to global warming will follow the simple rule that wet regions get wetter and dry regions get drier. A key implication of this rule is that climate model errors in the representation of precipitation and evaporation in the present climate lead to artificial simulated responses in a warming climate. Here we show that this simple rule can be applied separately to precipitation and evaporation over tropical oceans. We then use this rule to estimate the extent of the artificial response over tropical oceans to global warming in modern climate models, caused by errors in the representation of precipitation and evaporation. Overall, the artificial changes may increase the uncertainty in projections by up to 30% for precipitation and 15% for evaporation. Key Points Biases in the representation of the present hydroclimate lead to spurious but correctable projected changes in precipitation and evaporation A wet‐get‐wetter/dry‐get‐drier scaling bias adjustment can be applied separately to precipitation and evaporation The spurious changes increase uncertainty in precipitation and evaporation projections by up to 30% and 15% respectively