Abstract Details
| ID: | 1539 |
| Title: | Networks of palaeohydrological data from peatlands and the spatial structure of North American drought |
| Content: | Synoptic networks of late Holocene records of hydroclimate variation are important for assessing the spatial structure of past drought events and long-term dynamics of the coupled ocean-atmosphere system. Ombrotrophic peatlands are increasingly being used in these efforts, particularly because of recent advances in our understanding of peatland responses to climate change. A network of peatland records has recently been developed from sites in mid-continental and eastern North America using testate amoebae and measurements of peat humification. Bayesian age-depth modeling approaches were used to develop chronologies of past hydroclimate from individual sites, and stacked records were developed from sites in the Great Lakes region (n=4) and Maine (n=3). When viewed in conjunction with other continental records of late Holocene hydroclimate (e.g., tree-ring record from western United States) this network provides a regional-to-continental scale view of past moisture variation in North America spanning the past 3000 years. The records reveal that droughts during the Medieval Climate Anomaly and during the late 16th century were more widespread than previously recognized, extending from the western United States to Maine. Droughts spanning multiple decades with similarly widespread footprints have not occurred during the past century. Comparison to proxy sea surface temperature (SST) records and modeling studies suggests that anomalous SSTs in the Atlantic and Pacific may have contributed to the widespread droughts, although a full explanation requires additional research. Peatland archives are well suited to studies of past drought variability, and their wide distribution at mid- to high latitudes in the northern and southern hemispheres make them particularly useful in multi-archive syntheses of hydroclimate variation at hemispheric-to-global scales. |
| Session: | 12 Integrating peatland data for past climate and carbon cycle dynamics |
| Authors: |
Bob Booth |
| Presenter: | Bob Booth |
| Type: | oral |
