Sustainability Science Program

Overview

Sustainable Development of the Amazon and its Surrounding Regions: The Interplay of Changing Climate, Hydrology, and Land Use

Overview

This initiative is examining the linkages between land use decisions in Brazil and their impacts on climate and water availability within the Amazon and surrounding regions. Agricultural expansion and other land use transformation is continuing in the Amazon and surrounding regions as global demand for food and biofuel increases and regional economies expand. Analyses indicate that the conversion of forest and cerrado ecosystems to pastureland and agricultural crops creates warmer and drier atmospheric conditions than the native vegetation. In addition, human-induced climate change arising from increasing levels of greenhouse gases is also expected to push the region towards a warmer and drier state. This study will rigorously quantify the key sustainability thresholds for the hydrologic functioning of the Amazon basin and surrounding regions under different land transformation and climate change scenarios, focusing on its impacts on the hydropower and agricultural productivity.

The sustainable development problem
Agriculture and hydropower are two cornerstones of Brazil’s ongoing economic expansion. This initiative will examine the long-term sustainability of agriculture and hydropower in the Amazon basin and surrounding areas in the face of the human-driven changes in the region’s water cycle arising from land-use transformation and global climate change. 

Research questions
At what point does deforestation and associated increases in cultivated area in the Amazon and surrounding areas cause declines in rainfall large enough that the changes in region’s water cycle begin to significantly impact the integrity of the remaining forest ecosystems, the region’s agricultural productivity,  and its hydropower? Are these environmental responses to increasing land transformation and human-induced climate change relatively smooth or are there key thresholds beyond which abrupt changes occur?

Solving a practical problem of sustainable development
Continuing expansion of agriculture and hydropower are key components of Brazil’s economic development strategy for the 21st century. This project will help determine the environmental externalities of this development trajectory arising from the feedbacks of land-use transformation onto the region’s hydrologic cycle, and how this will interact with anthropogenic climate change arising from greenhouse gas emissions.

Research strategy
We developed a constrained implementation of a regional-scale coupled biosphere-atmosphere model ED2-BRAMS to explore the interactions between ecosystems, hydrology, and climate in the Amazon region. The ED2-BRAMS model is unique in its ability to realistically represent the dynamics of heterogeneous landscapes comprised mosaics of natural ecosystems and ecosystems impacted by human activities such as agriculture and forest harvesting and land-abandonment. We then used the constrained model to conduct a retrospective analysis of the impacts of climate and land-use change in the Parana River basin. Since the 1970s, river-flow in the Parana basin has increased despite reductions in rainfall. Our results indicate that these seemingly paradoxical observations can be explained by concomitant changes in land cover that occurred during this period. Simulations of the observed patterns of land-use change from the 1970s to the present day show that land-use is the primary driver of the changes in stream-flow, and can account for both increased annual total stream-flow and the observed increase in seasonality.

Following this retrospective analysis, we have initiated a forward-looking case study examining the expected impacts of climate and land-use change on the planned hydropower developments in the Tapajós River basin. Preliminary coupled atmosphere-biosphere model simulations of rainfall for the 2001-2009 period agree well with satellite-based estimates of the region’s precipitation patterns. Given the anticipated land-use and climate changes in the Amazon, our ongoing effort to evaluate the impacts associated with the hydrologic changes on the Tapajós river will be very timely and crucial, particularly as the Brazilian government plans to build a series of new hydropower facilities in the region in the near future.

During the remainder of the Initiative we will conduct prospective simulations to examine the sustainability of hydropower in Amazonia and the surrounding regions, and explore the key sources of uncertainty in the predicted changes in the region’s climate, hydrology and ecosystems.

Key components of this activity will be:

  1. new land-use change and climate scenarios based on the feedback from the hydropower stakeholder communities obtained from the May 2013 stakeholder workshop that was hosted by ANA (the Brazilian national water agency) and the scenarios used in the IPCC 5th assessment report. These will shape the coupled model simulations.
  2. Increased realism in the representation of agricultural landscapes within the terrestrial biosphere model.
  3. interfacing the output from the coupled biosphere-atmosphere simulation output with hydrologic models used to assessing hydropower implications of changes in precipitation and runoff.

We will also conduct a series of sensitivity analyses to identify the principal sources of uncertainties in predicting the future state of the region’s hydrologic cycle over the coming decades. 

Outreach
The work conducted under this project will be communicated to the scientific community through publication in scientific journals and presentation of results at major scientific meetings.  These include the annual Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) meetings that are held in the region, and the American Geophysical Union (AGU), a major forum for climate science research.

Our results will be communicated to the relevant practitioner communities in Brazil, drawing upon the experiences and feedback from the in-country stakeholder workshop that we held in Brazilia in May 2013. Angela Livino, a fellow funded through this project will attend a workshop at the ABRH (Water Resources Brazilian Association) meeting in Bento Gonçalves, Brazil in November 2013. The workshop is organized by The Nature Conservancy (TNC), Brazil as part of their Great Rivers Partnership (GRP) and will discuss the issues of power generation, river transportation and deforestation / forest uses in the Tapajos region.

Engaging colleagues from the region
We will engage with the Brazilian sustainable development, agricultural, and hydropower communities via workshops that will be held in Brazil. A key in-country liaison is Professor Marcos Heil Costa at the Federal University of Viçosa (UFV), a longstanding colleague of PI Moorcroft. As well as being a leading Brazilian climate researcher, Costa recently served as the coordinator of Climate Change at Secretariat of Policies and Programs of Research and Development (SEPED) in the Brazilian Ministry of Science and Technology. In addition the co-PI on the project, Professor John Briscoe, was the former Country Director for Brazil at the World Bank has excellent contacts with individuals in both agricultural and hydropower sectors.

Key participants will be representatives from ANA (the Brazilian National Water Agency), and governmental and non-governmental organizations involved in sustainable environmental development issues in Brazil, in particular The Nature Conservancy (TNC) Brazil and the World Wildlife Fund (WWF) Brazil. Other institutions that will be engaged in the workshops include: National Institute of Amazon Research (INPA), Brazilian Foundation for Sustainable Development (FBDS), National Institute of Space Research (INPE), International Program and the Amazon Scenarios Program (IPAM) and the Center for Sustainable Development (CDS) at University of Brasília (UnB) and the Brazilian National Energy Planning Agency (EPE).

We are planning to hold a pair of workshops during 2014 to engage with different components of the hydropower community.