Locating Risks to Biodiversity: A Carbon Balance Approach

Transcription

1 Locating Risks to Biodiversity: A Carbon Balance Approach CARBON PI: M. L. Imhoff,, NASA s s GSFC Co-I s: L. Bounoua, UMD s Earth System Science Interdisciplinary Center T. Ricketts and C. Loucks, World Wildlife Fund

2 Introduction Questions How much of Earth s terrestrial NPP-carbon (NPP-C) is required by the human population for food, fuel, and fiber? How does the rate of NPP-C demand compare to supply (NPP-C balance)? How does NPP-C balance vary regionally? How do socio-economic factors act as drivers of NPP-C demand? Where might the NPP-C balance crises be affecting food, energy, and biodiversity? Goals Explore the dynamics of human NPP-C demand and the carbon cycle. Use EO data to estimate the NPP-C supply of the planet. Create a spatially explicit NPP-C balance sheet for planet Earth. Explore the role of changing socio-economic conditions as drivers of change in global and regional NPP-C supply and demand. Explore the potential impact of NPP-C balance structure on biodiversity. Approach Develop process models interfacing with UN-FAO data on food, wood-fuel, and fiber consumption to estimate NPP-C demand at the landscape level. Create map of NPP-C demand through population indexing. Use AVHRR NDVI data to map 17 year average terrestrial NPP-C supply. Compare maps to make spatially explicit NPP-C balance sheet/map.

3 Comparing NPP Carbon Supply and Demand FAO STATS FAO STATS Methods: Develop Human Appropriation NPP (HANPP) Model (consumption-based) - Estimate the amount of NPP required in the field for food and fiber products reported in the United Nations Food and Agriculture Organization database (UNFAO-STATS). HANPP model Climate Data - Country Level and Product Specific: Annual Per Capita NPP-Carbon Demand by Country Vegetal Foods, Livestock-based Products, Wood, Paper, and Fiber. - Landscape Relevant: Bio-agronomic modules back-calculate the NPP required to produce the consumed products. Harvest, processing, and livestock parameters (literature). Separate parameterization for Developing Vs. Industrialized Countries. AVHRR 17year Ave. Monthly Max NDVI CIESIN Gridded Population CASA Make NPP Demand Map Apply HANPP of countries to population map from CIESIN using per Capita NPP consumption. Make NPP supply Map using satellite data. Compare NPP Supply with NPP Demand. Annual Sum NPP Supply NPP Demand NPP Carbon Balance

4 Results Avg. terrestrial NPP-C supply ( ) is 56.8 Pg C/yr. Discovered that global human population requires 20% of Earth s total NPP-C supply for food and fiber (Human NPP-C demand is 11.5 Pg C at 1995 population and consumption levels). Showed that balance between supply and demand varies widely among regions. (e.g., demand is 6% of supply in South America, 70% in Europe and Asia, 30,000% in major cities). Quantified how population growth and economic development will increase NPP-C demand in future years. Future steps Explore relationship between NPP-C demand and land surface change. Explore how NPP-C transport in bilateral trade. Explore how future potential future socio-economic changes affect NPP-carbon demand and land surface change.

5 NPP Carbon Demand as a % of Supply Global NPP Demand is 11.5 Pg C per year ( 20% of Supply) There are large regional and local variations 6% (South America) to over 70% (Europe and Asia), and from near 0% (Central Australia) to over 30,000% (New York City, Bejing). W. Europe North America S. Central Asia 24% 72% 300% South America 84% 6%

6 Conclusions The rate at which humans consume NPP-C C is a powerful aggregate measure of human impact on biosphere function. Global NPP-C C Demand is 20% of Supply with large regional and local variation (e.g., 6% in South America, 70% in Europe and Asia, 30,000% in major cities). Spatial Data on NPP-C C Supply and Demand illustrate the degree to which local populations depend upon NPP imports. The NPP-C C demand model structure (coupling with UNFAOSTATS) allows quantitative assessment of potential future impacts to NPP-C balance resulting from different policy and development scenarios. s. Publications M. L. Imhoff, L. Bounoua, T. Ricketts, C. Loucks, R. Harriss, and W. Lawrence. Human consumption of primary productivity. Nature (in press).