Dryness limits vegetation pace to cope with temperature change in warm regions

Climate change leads to increasing temperature and more extreme hot and drought events. Ecosystem capability to cope with climate warming depends on vegetation's adjusting pace with temperature change. How environmental stresses impair such a vegetation pace has not been carefully investigated. Here we show that dryness substantially dampens vegetation pace in warm regions to adjust the optimal temperature of gross primary production (GPP) ( TGPP opt) in response to change in temperature over space and time. TGPP opt spatially converges to an increase of 1.01 degrees C (95% CI: 0.97, 1.05) per 1 degrees C increase in the yearly maximum temperature (Tmax) across humid or cold sites worldwide (37 degrees S-79 degrees N) but only 0.59 degrees C (95% CI: 0.46, 0.74) per 1 degrees C increase in Tmax across dry and warm sites. TGPP opt temporally changes by 0.81 degrees C (95% CI: 0.75, 0.87) per 1 degrees C interannual variation in Tmax at humid or cold sites and 0.42 degrees C (95% CI: 0.17, 0.66) at dry and warm sites. Regardless of the water limitation, the maximum GPP (GPPmax) similarly increases by 0.23 g C m-2 day-1 per 1 degrees C increase in TGPP opt in either humid or dry areas. Our results indicate that the future climate warming likely stimulates vegetation productivity more substantially in humid than water-limited regions.

Automated summary

Climate change leads to increasing temperature and more extreme hot and drought events. The ability of vegetation to cope with climate warming depends on their adjusting pace with temperature change. However, the impact of environmental stresses on such vegetation pace has not been thoroughly investigated.