Saatchi, Sassan: Jet Propulsion Laboratory / Caltech (Project Lead)
Aragao, Luiz: National Institute for Space Research (INPE) (Co-Investigator)
Konings, Alexandra: Stanford University (Co-Investigator)
Moorcroft, Paul: Harvard University (Co-Investigator)
Schimel, David (Dave): JPL (Co-Investigator)
Xu, Liang (Alan): JPL (Co-Investigator)
Project Funding:
2017 - 2020
NRA: 2016 NASA: Carbon Cycle Science
Funded by NASA
Abstract:
Climate change is projected to alter both the climate mean condition and variability, leading to more intense climate extremes such as severe droughts. Recent Amazonian mega droughts from a combination of intensified El Nino and Atlantic Multi-decadal Oscillations (AMO) have drawn attention to the vulnerability of tropical forests to extreme water stress as their ecological processes are more sensitive to climate extremes than changes in mean states of climate. With potential changes of the ecosystem function, such as slowing down of the forest productivity and changes in tree demography and composition, extreme climate variability may cause major impacts on the ecosystem level carbon cycling, limiting the large carbon uptake of tropical forests. Ground measurements and satellite observations of the 2005 and 2010 mega-droughts in Amazonia have already shown anomalously extensive fires during the drought years and increasing tree mortality for a period after the droughts.
In this proposal, we use a combination of satellite observations on hydro-ecological variables combined with ecosystem modeling over Amazonia to quantify the impacts and legacy of droughts on the carbon stocks and fluxes of forests of Amazonia over a period of more than 15 years. The proposed research will focus on the magnitude and extent of the impacts of droughts on the carbon assimilation and dynamics of these forests by addressing the following questions:
1. How fast and to what degree do Amazon forests respond to and recover from extreme water stress?
2. What is the magnitude of the effects of recent drought and their legacy on the carbon stocks and fluxes of the Amazon forests?
3. To what extent does variation in forest structure and environment (climate & edaphic) impact the sensitivity and the ecological resilience of the Amazonian forests to climate variability and change?
Our research project is designed to quantify the impacts of the climate change and variability on the short and long-term carbon sequestration capacity of tropical systems. The results of the proposed work will improve our understanding of the response of tropical ecosystems to recent pervasive droughts and predict the function of the ecosystem when exposed to more frequent and extensive droughts in near future.
Publications:
Shi, M., Liu, J., Zhao, M., Yu, Y., Saatchi, S. 2017. Mechanistic Processes Controlling Persistent Changes of Forest Canopy Structure After 2005 Amazon Drought. Journal of Geophysical Research: Biogeosciences. 122(12), 3378-3390. DOI: 10.1002/2017JG003966
More details may be found in the following project profile(s):
