Sensitivity of Land Surface Temperature to Lengthened Vegetation Growing Season in Boreal Forest

Abstract

Vegetation phenology are important for shaping seasonal climate over the northern boreal forests. However, the biophysical effects of phenological changes on the land surface temperature (LST) are still unclear. Here, we estimated LST sensitivity to advanced start of growing season (SOS) and delayed end of growing season (EOS) during corresponding green-up and senescence periods over boreal deciduous forests based on experimental set of Community Land Model version 5. Estimated LST sensitivities to advanced SOS and delayed EOS during green-up and senescence periods were ？2.1 × 10？2 K day？1 and ？2.8 × 10？2 K day？1, respectively, denoting cooling land surface due to phenological changes. Reduced the aerodynamic resistance to SOS and EOS changes and relevant turbulent heat release could explain the higher LST sensitivity to EOS than that to SOS. Hence, the reduced aerodynamic resistance due to phenological shifts could be an important consideration for projecting seasonal climate change.