Regional feedbacks under changing climate and land-use conditions L. Batlle Bayer1, B. J. J. M. van den Hurk1,2, B. J. Strengers3, and J. G. van Minnen3 1IMAU – Institute for Marine and Atmospheric research Utrecht, Utrecht University, The Netherlands 2KNMI – Royal Netherlands Meteorological Institute, De Bilt, The Netherlands 3PBL – Netherlands Environmental Assessment Agency, Bilthoven, The Netherlands
Received: 29 February 2012 – Accepted: 08 March 2012 – Published: 02 April 2012
Abstract. Ecosystem responses to a changing climate and human-induced climate forcings
(e.g. deforestation) might amplify (positive feedback) or dampen (negative
feedback) the initial climate response. Feedbacks may include the
biogeochemical (e.g. carbon cycle) and biogeophysical feedbacks (e.g. albedo
and hydrological cycle). Here, we first review the most important feedbacks
and put them into the context of a conceptual framework, including the major
processes and interactions between terrestrial ecosystems and climate. We
explore potential regional feedbacks in four hot spots with pronounced
potential changes in land-use/management and local climate: sub-Saharan
Africa (SSA), Europe, the Amazon Basin and South and Southeast Asia. For
each region, the relevant human-induced climate forcings and feedbacks were
identified based on published literature.
When evapotranspiration is limited by a soil water deficit, heat waves in
Europe are amplified (positive soil moisture-temperature feedback). Drought
events in the Amazon lead to further rainfall reduction when water recycling
processes are affected (positive soil moisture-precipitation feedback). In
SSA, the adoption of irrigation in the commonly rainfed systems can modulate
the negative soil moisture-temperature feedback. In contrast, future water
shortage in South and Southeast Asia can turn the negative soil
moisture-temperature feedback into a positive one.
Further research including advanced modeling strategies is needed to isolate
the dominant processes affecting the strength and sign of the feedbacks. In
addition, the socio-economic dimension needs to be considered in the
ecosystems-climate system to include the essential role of human decisions
on land-use and land-cover change (LULCC). In this context, enhanced
integration between Earth System (ES) and Integrated Assessment (IA)
modeling communities is strongly recommended.
Citation: Batlle Bayer, L., van den Hurk, B. J. J. M., Strengers, B. J., and van Minnen, J. G.: Regional feedbacks under changing climate and land-use conditions, Earth Syst. Dynam. Discuss., 3, 201-234, doi:10.5194/esdd-3-201-2012, 2012.