Research of the Grinnell Resurvey Project

NSF Grant

NSF

As of February 2007, MVZ was awarded a National Science Foundation grant to pursue the Grinnell Resurvey Project. The full Award Abstract is posted here.

The Final Report was submitted in July 2012, and can be downloaded here.

There is intense societal and scientific interest in effects of global warming on species' distributions and diversity. However, because there are so few historical records with the detail necessary to measure multi-decadal responses to past warming, most attention has been on using models to predict future responses. The present study resurveys bird and mammal diversity across 80 high-elevation sites in California for which there is an extensive, museum-based record from the early 20th C. The aims are to (i) measure how changes in climate over the past 100 years have affected species diversity, (ii) test alternative methods for predicting effects of climate change on species' distributions, and (iii) using historically-verified models, predict responses to future climate change.

Climate Models

One of the primary research questions is, how have species changed from the original survey period to the present? One aspect of that question is whether or not climate change has played a role. To answer that, we needed to seek out and develop climate models for the historic period as well as the current. Researchers attempted to develop their own through a method of interpolation called Anusplin using weather station data. These Anusplin climate surfaces were compared it to another method, PRISM, which we contrast below.

For each of these methods we have reconstructed surfaces for two time periods for the Western US:

  1. Historic : 1900 - 1940
  2. Current : 1980-2005

Reconstructions made through Anusplin are available at 2 spatial resolutions:

  1. ~1km squared
  2. ~4km squared

Reconstructions from PRISM are only available at ~4km squared.

Direct comparisons of these two historic reconstructions of climate surfaces are described in detail in:

Parra, J.L. and W.B. Monahan. 2008. Influence of climate data uncertainty in modeling geographic responses of California mammals to 20th century climate change. Global Change Biology. Abstract


Data used for historic /modern climate comparisons
  • Anusplin at 4 km and 1 km resolution ( Parra and Monahan 2008) 
    • Historic Precipitation
    • Historic maximum Temperature
    • Historic mean Temperature
    • Historic minimum Temperature
    • Current Precipitation
    • Current maximum Temperature
    • Current mean Temperature
    • Current minimum Temperature
  • PRISM at 4 km and 1 km resolution (PRISM, Daly et al)
    • Same variables as above, and bioclimatically averaged variables (see Worldclim)

For access contact Michelle Koo.

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