Abstract
Abstract Widespread negative correlations between summertime-mean temperatures and precipitation over land regions are a well-known feature of terrestrial climate. This behavior has generally been interpreted in the context of soil moisture–atmosphere coupling, with soil moisture deficits associated with reduced rainfall leading to enhanced surface sensible heating and higher surface temperature. The present study revisits the genesis of these negative temperature–precipitation correlations using simulations from the Global Land–Atmosphere Coupling Experiment–phase 5 of the Coupled Model Intercomparison Project (GLACE-CMIP5) multimodel experiment. The analyses are based on simulations with five climate models, which were integrated with prescribed (noninteractive) and with interactive soil moisture over the period 1950–2100. While the results presented here generally confirm the interpretation that negative correlations between seasonal temperature and precipitation arise through the direct control of soil moisture on surface heat flux partitioning, the presence of widespread negative correlations when soil moisture–atmosphere interactions are artificially removed in at least two out of five models suggests that atmospheric processes, in addition to land surface processes, contribute to the observed negative temperature–precipitation correlation. On longer time scales, the negative correlation between precipitation and temperature is shown to have implications for the projection of climate change impacts on near-surface climate: in all models, in the regions of strongest temperature–precipitation anticorrelation on interannual time scales, long-term regional warming is modulated to a large extent by the regional response of precipitation to climate change, with precipitation increases (decreases) being associated with minimum (maximum) warming. This correspondence appears to arise largely as the result of soil moisture–atmosphere interactions.
Highlights
Temperature and precipitation are arguably the two most critical components of surface climate over land for both terrestrial ecosystems and human society
This atmospheric control reflects the absence of soil moisture depletion following evapotranspiration in expA, since soil moisture is overridden by climatological values at every time step in the models: in this context, soil moisture exerts no control on ET, and the atmosphere is left to drive ET variability
This confirms that soil moisture–atmosphere interactions are playing no role in T–P correlations in simulation expA in Fig. 3
Summary
Temperature and precipitation are arguably the two most critical components of surface climate over land for both terrestrial ecosystems and human society. Anticorrelation of terrestrial surface temperature and precipitation has been observed over a range of time scales and regions in many prior studies. The studies mentioned above indicate distinct behavior in terrestrial temperature–precipitation covariability for different seasons, Déry and Wood (2005) report significant anticorrelations between annualmean temperature and precipitation over land for observations over the twentieth century. Portmann et al (2009) suggest that a positive trend in precipitation over recent decades may account for the postulated ‘‘warming hole’’ in the southeastern United States
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
