Decreasing “alpine tundra” climatic type with global warming in the Tibetan Plateau

Abstract

Rapid elevation-dependent warming (EDW) in high mountain environments can accelerate the rate of change in permafrost and further induce the degradation of alpine tundra systems. However, how changes in area of alpine tundra response to EDW is difficult to be directly quantified at regional scales. Here, we project future changes in areal extent of the Koppen “alpine tundra” climate type in the Tibetan Plateau (TP), which is a potential indicator describing the climate conditions for the development of alpine tundra system, based on a suite of latest Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models under two emission scenarios (representative concentration pathways: RCP 4.5 and RCP 8.5). The results indicated that the Koppen “alpine tundra” climate type would gradually decrease in the TP for three future periods: 2011–2040, 2041–2070, and 2071–2100, especially under the RCP8.5 scenario. The decline in area of Koppen “alpine tundra” climate type mainly occurs above 2500 m above sea level (ASL) due to the EDW (> 10 °C) in the warmest months. The projected changes in area of “alpine tundra” climate type are overall consistent among different climate models, emission scenarios, and post-processing approaches (bias correction or not) used. The results obtained would thus deepen our understanding of future elevation-dependent warming and its potential influences on alpine tundra ecosystems in the Tibetan Plateau.