Dear Hubbard Brook Colleagues,

I thought the HBES community would be interested in a paper that has been recently accepted for publication in Scientific Reports (Nature).  The title of the paper is “Arctic Vortex changes alter the sources and isotopic values of precipitation in northeastern US” with the following authors:

T. Puntsag (an international Ph.D. [GPES] student from Mongolia), M.J. Mitchell (Distinguished Professor Emeritus), J. Campbell (U.S. Forest Service, Durham, NH), E. Klein (U. of Alaska Anchorage), G. Likens (Carey IES, Millbrook, NY) and J. Welker (U. of Alaska Anchorage).

This paper shows a close linkage between climate change, the hydrological cycle and the changing water sources from precipitation over the study period. Altered atmospheric circulation, reductions in Arctic sea ice, ocean warming, and changes in evaporation and transpiration are driving changes in the global hydrologic cycle. Precipitation isotopic (d18O and d2H) measurements can help provide a mechanistic understanding of hydrologic change at global and regional scales. To study the changing water cycle in the northeastern US, we examined the longest (1968-2010) record of precipitation isotope values, collected at the Hubbard Brook Experimental Forest in New Hampshire, US (43o56'N, 71o45'W). We found a significant reduction in d18O and d2H values over the 43-year record, coupled with a significant increase in d-excess values. This gradual reduction in d18O and d2H values unexpectedly occurred during a period of regional warming. We provide evidence that these changes are governed by the interactions among the Atlantic Multidecadal Oscillation, loss of Arctic sea ice, the fluctuating jet stream, and regular incursions of polar air into the northeastern US.

I have provided files of a preprint and supplemental information of this article that are attached to this email as PDF files.

Tamir Puntsag is continuing to work on her Ph.D. Dissertation and analyses will include comparison over time (among years) and among watersheds of changes in the stable isotopes of water in precipitation and stream discharge.  She is will also do a paper on the seasonal changes in water isotopes in precipitation and stream discharge.

If you have any questions or need any further information, please let me know.

Myron

Myron J. Mitchell

Distinguished Professor Emeritus

SUNY-ESF

1 Forestry Drive

Syracuse, NY 13210

Email: mitchell@syr.edu

Phone: 315-470-6765

Fax: 315-470-6996