Utility of glacier observations in climate change detection and attribution studies

In middle and low latitudes glacier mass balance is a sensitive function of temperature, since most glacier ice lies at or near the melting point. Mass balance is thus a non-delayed indicator of interannual change in climate state. Changes in terminus position or other morphological glacier characteristics, on the other hand, are mediated by ice flow, and necessitate consideration of a lag, or response time if they are to interpreted in terms of climate shifts. In addition, complications arise in the interpretation of either type of record, due to natural climate variability on the decadal-to-centennial time scales that are of the most interest in climate change detection and attribution studies. Here we attempt to assess the utility of observations on glaciers for such studies in light of these complicating factors.