Thursday, 18 January 2007: 9:00 AM
Impact of Automated Surface Observing Systems (ASOS) on the long-term temperature record: climatological significance
206A (Henry B. Gonzalez Convention Center)
The integrity of long-term temperature records is of the utmost importance. Especially now, government policy decisions about climate change must be made based upon the current long-term temperature record. The implementation of Automated Surface Observing Systems (ASOS) at many meteorological observation sites in the past 15 years may have compromised the integrity of the long-term records at these sites. Previous research suggests that ASOS temperature measurements are on the order of 1°F cooler than the replaced instrumentation. Using a 30-year temperature record at a number of ASOS sites, this study investigates the significance of the instrumentation change on the climate record. This significance is tested using monthly temperature normals and comparing with normals from Co-op stations. Linear regression and bootstrapping techniques are used to create alternate data sets used in this study to assess the impact of ASOS. The results suggest that the differences are 1-2°F, however the differences are not statistically significant for all months.