Spatiotemporal variations in the difference between satellite‐observed daily maximum land surface temperature and station‐based daily maximum near‐surface air temperature

Abstract

There is an increasing demand to integrate land surface temperature (LST) into climate research due to its global coverage, which requires a comprehensive knowledge of its distinctive characteristics compared to near‐surface air temperature (Tair). Using satellite observations and in situ station‐based data sets, we conducted a global‐scale assessment of the spatial and seasonal variations in the difference between daily maximum LST and daily maximum Tair (δT, LST − Tair) during 2003–2014. Spatially, LST is generally higher than Tair over arid and sparsely vegetated regions in the middle‐low latitudes, but LST is lower than Tair in tropical rainforests due to strong evaporative cooling, and in the high‐latitude regions due to snow‐induced radiative cooling. Seasonally, δT is negative in tropical regions throughout the year, while it displays a pronounced seasonality in both the midlatitudes and boreal regions. The seasonality in the midlatitudes is a result of the asynchronous responses of LST and Tair to the seasonal cycle of radiation and vegetation abundance, whereas in the boreal regions, seasonality is mainly caused by the change in snow cover. Our study identified substantial spatial heterogeneity and seasonality in δT, as well as its determinant environmental drivers, and thus provides a useful reference for monitoring near‐surface air temperature changes using remote sensing, particularly in remote regions.

A spatiotemporal analysis of the relationship between near‐surface air temperature and satellite land surface temperatures using 17 years of data from the ATSR series

“…These spatial patterns are very similar to those reported by Lian et al . [], who analyzed differences between MODIS/Aqua maximum monthly LSTs and T max from CRU‐TS. The tendency of LST day to fall below T max at high latitudes and during winter months can be explained by the lower insolation in these regimes resulting in cold LSTs, whereas T 2m is higher because the air has passed over warmer SSTs.…”

“…[] present an analysis of the global relationship between the annual maximum LST and T 2m using 7 years of data from MODIS/Aqua, which has a local solar overpass time of ~1:30 P.M. More recently, Lian et al . [] used 12 years of MODIS/Aqua data to analyze the global relationship between maximum monthly T 2m ( T max ) and monthly maximum LST.…”

Air temperature optima of vegetation productivity across global biomes

“…As shown in Supplementary Figure 22, the Topt_LSTeco is similar to Topteco over tropical savannas. However, over moist tropical forests Topt_LSTeco is lower than Topteco, which can be explained by the lower daytime surface temperature than air temperature as a result of strong evapotranspiration effects 71,73 . This ecosystem-dependent difference between Topt_LSTeco and Topteco suggests that the leaf thermal regulation mechanism through the physiological and morphological changes 72 is an important ecosystem process shaping spatial variations of Topteco.…”

Remote sensing of earth’s energy budget: synthesis and review

“…Note that land surface air temperature (T air ) is often needed for various applications. LST is not equal to surface air temperature numerically (Good et al 2017;Lian et al 2017). For example, LST is generally higher than Tair over arid and sparsely vegetated regions in the middle-low latitudes, but LST is lower than Tair in tropical rainforests due to strong evaporative cooling, and in the high-latitude regions due to snow-induced radiative cooling.…”