Jim Johnstone

James A. Johnstone, Ph.D. (Berkeley 2008)                                        Climatologist 'Dr. Fog'      
Seattle, WA 

Available for scientific, business consultation, speaking engagements. 


Coastal NE Pacific temperatures respond to pressure/wind variations and changes:  

Johnstone, J. A. and Mantua, N. J. 2014. Atmospheric controls on northeast Pacific temperature variability and change, 1900-2012.        Proceedings of the National Academy of Sciences.

pdf   PNAS link

Summary and FAQ from the NOAA SW Fisheries Science Center

Seattle Times

New York Times

Monthly northeast (NE) Pacific sea level pressure (SLP) and sea surface temperature (SST). The red curve illustrates the monthly SST anomaly in a NE Pacific 'Arc' region that stretches around the North American coast from Alaska to California and offshore toward Hawaii.  The blue curve shows monthly SST modeled from current and prior SLP over the open NE Pacific, which largely regulates wind speeds over the Arc.  

SST tends to follow SLP by about 4 months, and SLP is oriented with higher index values reflecting lower pressure.  Lower SLP corresponds generally with weaker winds, and warmer surface waters.  Study data covered the period from 1900-2012. More recent data (January 2013 - August 2014) are marked with the shaded bar.  Recent warming in the past 12 months was generated largely by low SLP and weakening of the ocean winds.

1900-Aug 2014

1980-Aug 2014

Coast redwood responses to climate

Johnstone, J. A., Roden, J. S. and Dawson, T. E. 2013. Oxygen and carbon stable isotopes in coast redwood tree rings respond to spring and summer climate signals. Journal of Geophysical Research: Biogeosciences 118, 1438-1450.  pdf

Northern California fog

Johnstone, J. A. and Dawson, T. E. 2010. Climatic context and ecological implications of summer fog decline in the coast redwood region. Proceedings of the National Academy of Sciences 107, 4533-4538. pdf    PNAS link

Western US precipitation

Johnstone, J. A. 2010. A quasi-biennial signal in western US hydroclimate and its global teleconnections. Climate Dynamics 36, 663-680.  pdf