Climatic trends over the Tibetan Plateau during 1971–2000

Abstract

Trends of annual and monthly temperature, precipitation, potential evapotranspiration and aridity index were analyzed to understand climate change during the period 1971-2000 over the Tibetan Plateau which is one of the most special regions sensitive to global climate change. FAO56-Penmen-Monteith model was modified to calculate potential evapotranspiration which integrated many climatic elements including maximum and minimum temperatures, solar radiation, relative humidity and wind speed. Results indicate generally warming trends of the annual averaged and monthly temperatures, increasing trends of precipitation except in April and September, decreasing trends of annual and monthly potential evapotranspiration, and increasing aridity index except in September. It is not the isolated climatic elements that are important to moisture conditions, but their integrated and simultaneous effect. Moreover, potential evapotranspiration often changes the effect of precipitation on moisture conditions. The climate trends suggest an important warm and humid tendency averaged over the southern plateau in annual period and in August. Moisture conditions would probably get drier at large area in the headwater region of the three rivers in annual average and months from April to November, and the northeast of the plateau from July to September. Complicated climatic trends over the Tibetan Plateau reveal that climatic factors have nonlinear relationships, and resulte in much uncertainty together with the scarcity of observation data. The results would enhance our understanding of the potential impact of climate change on environment in the Tibetan Plateau. Further research of the sensitivity and attribution of climate change to moisture conditions on the plateau is necessary.

Changes in daily climate extremes in the eastern and central Tibetan Plateau during 1961–2005

“…[34] Compared with change in temperature, there is no agreement yet for precipitation change in the TP which mainly contribute to the complex terrain and sparse meteorological stations [Du and Ma, 2004;Li and Kang, 2006;Wu et al, 2007]. Some experts divide the TP into nine subregions in terms of precipitation variation regimes and find that some subregions became drier but others wetter [Lin and Zhao, 1996].…”

Millennial temperature reconstruction based on tree-ring widths of Qilian juniper from Wulan, Qinghai Province, China

“…To determine whether the increasing trend of tree-ring width index in the recent decades is due to the "fertilization effect" of CO 2 [34] or the increasing of the precipitation [35] , we compared it with the tree-ring width index from the low forest limit (3600 m a.s.l.) in the Halihatu Park [22] .…”

Spatial-Temporal Patterns and Controls of Evapotranspiration across the Tibetan Plateau (2000–2012)

“…The temperature in the region has risen at an average of 0.05 ∘ C per year from 1981 to 2010, and a warming trend of 0.02 ∘ C per year was observed in the 30 years before 2000 [38]. The daytime temperature is greater than 10 ∘ C in the growing season from June to September [39,40].…”