Fig. 1. Linear trends for (a) Ta, average annual air temperature; (b) MAT, maximum air temperature; (c) MIT, minimum air temperature; (d) EMAT, extreme maximum air temperature; (e) EMIT, extreme minimum air temperature; (f) TP, total precipitation; (g) MAP, maximum precipitation; (h) Ea, average vapor pressure; (i) RH, average relative humidity; (j) MIRH, minimum relative humidity; (k) VPD, average vapor pressure deficit; (l) SP, percentage of sunshine; (m) SH, sunshine hours; and (n) WS, average wind speed; from 2000 to 2011 based on data from 69 meteorological stations on the Tibetan Plateau.

Fig. 2. Linear trends for the annual drought severity index (DSI) from 2000 to 2011, for different vegetation types on the Tibetan Plateau

Fig. 3. Drought severity index trend from 2000 to 2011 on the Tibetan Plateau

Fig. 4. Relationships of the linear trend of the annual drought severity index (Slope_DSI) with climate variables on the Tibetan Plateau. (a) average annual temperature (Ta); (b) maximum annual temperature (MAT); (c) minimum annual temperature (MIT); (d) extreme maximum annual temperature (EMAT); (e) extreme minimum annual temperature (EMIT); (f) annual precipitation (TP); (g) maximum annual precipitation (MAP); (h) average annual vapor pressure (Ea); (i) annual sunshine percentage (SP); (j) annual sunshine hours (SH); and (k) average annual wind speed (WS).

Fig. 5. Relationships between the linear trend of the annual drought severity index (Slope_DSI) and the linear trends of several climate factors: (a) maximum annual temperature (Slope_MAT); (b) extreme maximum annual temperature (Slope_EMAT); (c) extreme minimum annual temperature (Slope_EMIT); (d) annual precipitation (Slope_TP); (e) annual sunshine percentage (Slope_SP); and (f) annual sunshine hours (Slope_SH).

Fig. 6. Annual trends for (a) Ta, average air temperature; (b) MAT, maximum air temperature; (c) MIT, minimum air temperature; (d) EMAT, extreme maximum air temperature; (e) EMIT, extreme minimum air temperature; (f) WS, average wind speed; from 2000 to 2011 at 69 meteorological stations on the Tibetan Plateau.

Fig. 7. Annual trends for (a) TP, total precipitation; (b) MAP, maximum precipitation; (c) Ea, average vapor pressure; (d) RH, average relative humidity; (e) MIRH, minimum relative humidity; (f) VPD, average vapor pressure deficit; from 2000 to 2011 at 69 meteorological stations on the Tibetan Plateau.

Fig. 8. Annual trends for (a) SP, percentage of sunshine; (b) SH, sunshine hours; from 2000 to 2011 at 69 meteorological stations on the Tibetan Plateau.

Fig. 9. Correlation coefficients of the drought severity index (DSI) with: (a) Ta, average air temperature; (b) MAT, maximum air temperature; (c) MIT, minimum air temperature; (d) EMAT, extreme maximum air temperature; (e) EMIT, extreme minimum air temperature; (f) WS, average wind speed; from 2000 to 2011 at 69 meteorological stations on the Tibetan Plateau.

Fig. 10. Correlation coefficients of the drought severity index (DSI) with: (a) TP, total precipitation; (b) MAP, maximum precipitation; (c) Ea, average vapor pressure; (d) RH, average relative humidity; (e) MIRH, minimum relative humidity; (f) VPD, average vapor pressure deficit; from 2000 to 2011 at 69 meteorological stations on the Tibetan Plateau.

Fig. 11. Correlation coefficients of the drought severity index (DSI) with annual: (a) SP, percentage of sunshine; (b) SH, sunshine hours; from 2000 to 2011 at 69 meteorological stations on the Tibetan Plateau.