Comments on “Microclimate Exposures of Surface-Based Weather Stations”

e commend Davey and Pielke (2005) for their recent assessment of site exposures around U.S. Historical Climatology Network (USHCN) stations in eastern Colorado. In this brief note we comment on two important points raised in their analysis. First, we provide some background on USHCN and discuss weakness in USHCN site exposure documentation. Second, we clarify the logic behind the application of USHCN in climate change studies, emphasizing the relative importance of station exposures therein. We close with a short discussion of how the U.S. Climate Reference Network, which was developed in part to control for exposure problems, will increase confidence in future estimates of climatic change.