The GEAT department is pleased to welcome Dr. Jiafu Mao from Oak Ridge National Laboratory as our first seminar speaker for Fall 2017!
Title: “Driving mechanisms and feedbacks of the land greening”
When: Tuesday, August 29 @ 4:10 pm
Where: 2050 Agronomy Hall
Bio: Dr. Mao studies the response and feedback of land surface to climate change. His work primarily involves understanding hydrology, carbon cycling, and vegetation dynamics in the terrestrial ecosystems with field measurements, satellite data, process-oriented land surface and Earth system models; investigating the land surface response to multiple-factor global change and to attribute the variations of terrestrial ecosystem dynamics to natural and anthropogenic drivers; and global scale coupling research primarily concentrating on land-climate interactions with the integrated Earth system modeling framework. His research has been published in leading journals including Nature Climate Change, Nature Communications, Scientific Reports, Biogeosciences, Global Change Biology and Journal of Climate among others.
Abstract: The land greening, characterized by the change of vegetation indices, has been documented to significantly increase over the past 3 decades, especially in the northern extratropical land surface. Drivers of this enhanced vegetation growth have been extensively investigated using multiple estimates from observed and modeled datasets and various statistical methods. Spatialtemporal changes of the main climate drivers (e.g., temperature, precipitation and radiation) have been widely accessed to modulate the variation in vegetation growth. The combined anthropogenic effects, particularly the rising atmospheric concentrations of well-mixed GHGs, was recently clearly identified as the dominant factor controlling this observed land greening. On the other hand, the enhancement of vegetation activity can potentially accelerate the photosynthetic removal of atmospheric CO2 and decrease the surface air temperature causing a negative forcing on climate system. Also, through the complicated biophysical feedbacks (e.g., the increased evapotranspiration and absorption of solar radiation), the land greening can intensify or diminish negative climate forcing induced via its biogeochemical feedbacks. Future vegetation growth and feedbacks, however, remain to be determined because of nonlinear human-ecosystem-climate interactions under global warming.