Insolation, Precipitation, and Moisture Maps for a Virginia Geographic Information System
Climate information is valuable in understanding the ecology of systems affecting wildlife. This information is often unavailable at the landscape scale. This study evaluated the applicability of several climate factor estimates at the landscape-scale, and illustrated the usefulness of estimated climate factors in ecological investigations.
Climate variables estimated for each month of the year were solar radiation, temperature, precipitation, and potential evapotranspiration. Map layers for combined temperature and precipitation, and a moisture index were also created.
Accuracy of the estimates for temperature and precipitation for each 300 m x 300 m pixel were quantitatively assessed. The methods used estimated mean monthly temperature within 1 degree C. Precipitation estimates were within 9 mm of actual recorded value. The estimates for monthly solar radiation were qualitatively assessed, and provided a reasonable relative index to actual solar radiation. Estimates of potential evapotranspiration were determined to be reasonably accurate.
Landscape-scale estimated climate factors were used in 2 case studies. The first used logistic regression to examine the importance of climate factors to the observed distribution of 21 select forest cover-types in Virginia.The second compared the observed climate characteristics for the distributions of 3 species of terrestrial salamanders in Virginia. Winter temperature was the most important climate variable in determining forest cover-type distribution. Several differences in the climate characteristics of the 3 salamander distributions were observed and discussed. The conclusions of this study were that landscape-scale climate factors can be accurately estimated, and the estimates may be helpful in ecological investigations.