Forest Ecosystem Ecology at UW-Madison

NASA. S.T. Gower (PI), J.M. Norman (Co-PI), G. Diak (Co-PI) and K. Davis (Co-PI). 1998-2000.

The objective of this proposed work is to provide a unique and cost-effective set of verification and supporting measurements for ASTER (the Advanced Spaceborne Thermal Emission and Reflection Radiometer) land-surface temperature and emissivity and MODIS (the Moderate-Resolution Imaging Spectroradiometer) surface temperatures and vegetation-related products. The ASTER/MODIS products to be directly validated in this program are:

Land surface temperature (LST) and emissivity at the scale of ASTER and MODIS pixels;

Leaf Area Index (LAI);

Fraction Intercepted Photosynthetically Active Radiation (FIPAR);

Above-Ground Net Primary Production (NPP) and the net ecosystem CO2 exchange (NEE);

Snow and land cover

The above tasks will be accomplished by enhancing the measurement capabilities of an existing Ameriflux tower situated in northern Wisconsin and also by making detailed complementary in-situ measurements on scales ranging from the flux footprint of the tower to the pixel sizes of ASTER and MODIS. Additionally, we will compare flux measurements made by tower-based instrumentation to values obtained from a calibrated remote sensing method and to those derived from vegetation characteristics, estimated both from in-situ measurements and remote-sensing data. Remote sensing and in-situ data will be used to estimate Photosynthetically Active Radiation (PAR) for the area surrounding the tower location.

The project will be a collaboration among the University of Wisconsin-Madison Department of Soil Science, Department of Forest Ecology and Management, the University of Wisconsin-Madison Space Science and Engineering Center and the University of Minnesota Department of Soil, Water and Climate.

Relevant Publications
Anderson, MC, JM Norman, GR Diak and WP Kustas. 1997. A two-source time integrated model for estimating surface fluxes for thermal infrared satellite observations. Rem. Sens. Environ. 60: 195-216.

Chen, J, PW Rich, ST Gower, JM Norman and S Plummer. 1997. Leaf area index of boreal forests: Theory, techniques, and measurements. J. Geophys. Res. 102 (D24): 29,429-29,443.

Diak, GR, WL Bland and JR Mecikalski. 1996. A note on first estimates of surface insolation from GOES-8 visible satellite data. Agr. For. Meteor. 82: 219-226.

Fassnacht, KS, ST Gower, MD MacKenzie, EV Nordheim and TM Lillesand. 1997. Estimating the leaf area of north central Wisconsin forests using the Landsat Thematic Mapper. Remote Sens. Environ. 61: 229-245.

Fassnacht, KS and ST Gower. 1997. Interrelationships among the edaphic and stand characteristics, leaf area index, and aboveground net primary production of upland forest ecosystems in north central Wisconsin. Can. J. For. Res. 27: 1058-1067.