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5 CONCLUSION - RELEVANCE TO THE KYOTO PROTOCOL
The high spatial resolution radiance calibrated map of the nighttime lights of the world and the depiction of trace gas
emissions from fossil fuel consumption has two primary applications relevant to the Kyoto Protocol:
5.1 Inverse modeling to estimate the magnitude of regional land-atmosphere and ocean-atmosphere fluxes.
Because nearly the entire Earth surface can exchange carbon with the atmosphere, it is quite difficult to make reliable
measurements of the carbon fluxes between major reservoirs. For example, how is it possible to estimate the annual
quantity of carbon absorbed by the land surface in the United States? The approach that has been developed to estimate
these fluxes is to analyze continuous observations of trace gas concentrations from networks of sites which integrate
regional carbon fluxes. These measurements come from tall towers, high altitude observatories, aircraft and sea surface
sites. The measurements document the spatial and temporal distributions of carbon gases. The magnitude of sources
and sinks are estimated using a process known as "inverse modeling". At present, only a small number of independent
source/sink components can be reliably estimated by inverse analysis and only at the largest spatial scales (e.g. Northern
Hemisphere). A major limitation of current inverse modeling is that source inputs do not include the fine spatial and
temporal detail known to be present in the pattern of fossil fuel consumption. For instance, current modeling of annual
trace gas emissions from fossil fuel combustion are simply based on national statistics on the consumption of various
types of fossil fuel products. In actuality, trace gas emissions associated with fossil fuel combustion are concentrated at
major point sources (such as electric power plants) and in the vicinity of human population centers. Incorporation of a
high spatial resolution depiction of trace gas emissions from these sources is expected to lead to major improvements in
the spatial resolution and accuracy of current inverse modeling efforts.
5.2 Evaluating the Validity of National Trace Gas Emission Estimates. Under the United Nations Framework
Convention on Climate Change and the Kyoto Protocol nations of the world are beginning to report their annual trace
gas emissions and setting targets for stabilization or reduction in their emissions. Independent methods for evaluating
the magnitude of emissions and changes in emissions are crucial to the success of any international agreements. If it
cannot be demonstrated that the nationally reported emissions can be confirmed and validated by independent means the
agreements may never be ratified. Preliminary evidence suggests that it is possible to evaluate the veracity of national
emission estimates by searching for outliers in comparisons of OLS derived cumulative radiances versus reported
emissions. within clusters of countries having comparable levels of economic development.
ACKNOWLEDGMENTS
The authors gratefully acknowledge the U.S. Air Force, Defense Meteorological Satellite Program (DMSP) and the Air
Force Weather Agency for their cooperation in the acquisition of the reduced gain OLS data used in this study. This
research was supported in part by the NASA EOS Interdiciplinary Science (IDS) Project: Assessing the Impact of
Expanding Urban Land Use on Agricultural Productivity Using Remote Sensing Data and Physically-Based Soil
Productivity Models.
REFERENCES
Elvidge, C.D., Baugh, K.E., Kihn, E.A., Kroehl, H.W., Davis, E.R., 1997. Mapping of city lights using DMSP
Operational Linescan System data. Photogrammetric Engineering and Remote Sensing, v. 63, pp. 727-734.
Elvidge,C.D., Baugh, K.E., Dietz, J.B., Bland, T., Sutton, P.C., Kroehl, H.W. 1999. Radiance calibration of DMSP-
OLS low-light imaging data of human settlements. Remote Sensing of Environment, v. 68, pp. 77-88.
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000. 401
