We continue work on effects of changing climate on hydrology and biogeochemistry of forest watersheds. There are two components to this work. First we continue long-term measurements and experiments on climate change at Hubbard Brook. A focus of this work is on winter climate change, including effects on snowpack accumulation and below ground winter processes. We believe that climate change is driving the northern forest toward a condition of oligiotrophication (Groffman et al., 2018). This research has expanded with an NSF-funded project examining the effects of ice storms on the structure and function of the northern forest. Plots were established and experimental icing treatments ice storm conducted during winters 2016 and 2017. The National Science Foundation developed a video on this research project . I was invited to give a presentation on this ice storm at an American Geophysical Union Chapman Conference on effects of extreme climatic events in January 2017.

The second component of this research program on climate change effects is the application of statistically-down scaled climate projections from global general circulation models (GCMs) as inputs to PnET-BGC to simulate the long-term hydrology and hydrochemical response to forest watersheds to future climate change. Simulations have been conducted at long-term watershed sites across the US (e.g., Hubbard Brook, NH; Huntington Forest, NY; Sleepers River, VT; Fernow Experimental Forest, WV, Niwot Ridge CO, Loch Vale, CO, H.J. Andrews, OR) (Zheng Dong).

Figure 6. Inputs of coarse woody debris to plots of different levels of experimental icing at the
Hubbard Brook Experimental Forest, NH; Low ¼ inch. Mid ½ inch and High ¾ inch.

Current Work on Climate Change

References:

Dong, Z., C.T. Driscoll, K. Hayhoe, S. Johnson, J. Campbell, A. Pourmokhtarian, A. Stoner. In review. Dynamics of water, carbon, and nitrogen under future climate change in an old-growth Douglas-fir forest. Water Resources Research.

Groffman, P. M., C. T. Driscoll, J. Durán, J. Campbell, L. Christenson, T. Fahey, M.  Fisk, C. Fuss, G. Likens, G. Lovett, L. Rustad and P. Templer. 2018. Nitrogen oligotrophication in northern hardwood forests. Biogeochemistry. doi:10.1007/s10533-018-0445-y.