NorWeST announces stream temperature climate scenarios for upper Missouri

stream thermal-scape for upper MissouriStream temperature climate scenarios for the upper Missouri (SW Montana) that were developed from data the local aquatics community contributed are now available on the NorWeST website. The stream temperature database for this area is a compilation from the more than a dozen resource agencies and consists of 1,145 summers of monitoring effort at 578 unique stream sites. The NorWeST team has done its best to develop “value added” products from these data that we hope are useful to you. These products consist of three basic things, all of which can be readily summarized, displayed, or queried in ArcMap and other databases.

  1. GIS shapefiles showing the temperature predictions from an accurate model fit to all the data (r2 = 0.91; Average prediction error = 1.17°C) and used to develop a consistent set of historical climate scenario maps at 1-kilometer resolution for all 25,000 stream kilometers in this area. Historical scenarios consist of each year’s mean August stream temperature from 1993-2011 and two scenarios that are 10- and 19-year averages over this period. Scenarios representing future conditions will be forthcoming but are also easily derived from the historical average scenarios now available. We modeled mean August temperature because it’s the one month monitored most consistently across the region, it allowed us to use the largest proportion of everyone’s data in the model, because August is a thermally stressful period for many fishes, and it’s also relatively easy to directly link a monthly mean stream temperature model to outputs from a global climate model to create an integrated system that ensures the most accurate climate scenarios.
  2. GIS shapefiles showing the precision associated with the temperature model predictions, which is useful for identifying areas in streams that are not redundant with existing information and could aid in designing efficient monitoring strategies. 
  3. Daily summaries (max/min/mean) of temperature data (that we have permission to distribute) and georeferenced locations of monitoring sites across all agencies to facilitate coordinated monitoring efforts and new temperature research.

Thanks again to everyone for a willingness to share data and make this project possible. We hope the NorWeST data products are useful to you and help enable more efficient use of the resources we have to conserve and manage aquatic species and their habitats. If you have any questions or concerns regarding the temperature data summaries, please contact Sherry Wollrab or Gwynne Chandler. If you have any questions regarding the ArcMap GIS files, please contact Dave Nagel. If you have more general questions about the project, please contact one of the scientists listed below. 

The NorWeST temperature team,
Dan Isaak, Seth Wenger, Erin Peterson, Jay Ver Hoef, Charlie Luce, Steve Hostetler, Jason Dunham, Jeff Kershner, Brett Roper

>> Visit NorWeST
>> View stream thermal-scape map for upper Missouri