Agriculture, fisheries, and ecosystems will be increasingly compromised over the next century by climate change impacts. Farmers can explore new crop options, but these adaptations are not cost- or risk-free. Moreover, adaptive capacity, which varies throughout the region, could be overwhelmed by a changing climate.

This finding is from chapter 16 of Climate Change Impacts in the United States: The Third National Climate Assessment.

Process for developing key messages: Results of the Northeast Regional Climate assessment workshop that was held on November 17-18, 2011, at Columbia University, with approximately 60 attendees, were critically important in our assessment. The workshop was the beginning of the process that led to the foundational Technical Input Report (TIR).5f2be58e-4fcf-439c-bba8-1ed29be711fe That 313-page report consisted of seven chapters by 13 lead authors and more than 60 authors in total. Public and private citizens or institutions who service and anticipate a role in maintaining support for vulnerable populations in Northeast cities and communities indicated that they are making plans to judge the demand for adaptation services. These stakeholder interactions were surveyed and engaged in the preparation of this chapter. We are confident that the TIR authors made a vigorous attempt to engage various agencies at the state level and non-governmental organizations (NGOs) that have broader perspectives. The author team engaged in multiple technical discussions via teleconferences, which included careful review of the foundational TIR5f2be58e-4fcf-439c-bba8-1ed29be711fe and approximately 50 additional technical inputs provided by the public, as well as the other published literature and professional judgment. Discussions were followed by expert deliberation of draft key messages by the authors and targeted consultation with additional experts by the lead author of each key message.

Description of evidence base: The key message summarizes extensive evidence documented in the Northeast Technical Input Report.5f2be58e-4fcf-439c-bba8-1ed29be711fe Technical Input reports (48) on a wide range of topics were also received and reviewed as part of the Federal Register Notice solicitation for public input. The Traceable Account for Key Message 1 provides the evidence base on sea level rise, flooding, and precipitation. Various regional assessments were also consulted to capture key issues, concerns and opportunities in the region with particular focus on managed (agriculture and fisheries) and unmanaged (ecosystems) systems (for example, Buonaiuto et al. 2011; Wolfe et al. 20114c695b45-dbf9-4485-be19-df4a292ec02b 95ba9f76-77f9-481d-8137-6600f5a95d84 bdc2678b-d11f-4fb5-abf4-ba646dd7e582). Species and ecosystem vulnerability have been well documented historically in numerous peer-reviewed papers in addition to the ones cited in the TIR.5f2be58e-4fcf-439c-bba8-1ed29be711fe There have also been many examples of impacts on agriculture of climate variability and change in the Northeast (for example, Wolfe et al. 200841452674-2b8f-472c-8388-02c670541943). Most note that there is potential for significant benefits associated with climate changes to partially offset expected negative outcomes for these managed systems (for example, Hatfield et al. 2011a2704ef3-5be4-41ee-8dfa-4c82e416a292)

New information and remaining uncertainties: Important new evidence (cited above, plus Najjar et. al. 2010,11bd4ad9-197f-4041-bfef-ab4c405c7cac for example) confirmed many of the findings from the prior Northeast assessment (http://nca2009.globalchange.gov/northeast) which informed the 2009 NCA.e251f590-177e-4ba6-8ed1-6f68b5e54c8a These new sources also relied on improved models that have been calibrated to new observational data across the region. Agriculture, fisheries, and ecosystems in the Northeast are strongly linked to climate change and to other changes occurring outside the region and beyond the boundaries of the United States. These changes can influence the price of crops and agricultural inputs such as fertilizer, for example, as well as the abundance of ecosystem and agricultural pests and the abundance and range of fish stocks. Other uncertainties include imprecise understandings of how complex ecosystems will respond to climate- and non-climate-induced changes and the extent to which organisms may be able to adapt to a changing climate.

Assessment of confidence based on evidence: Based on our assessment, we have very high confidence for climate impacts (especially sea level rise and storm surge) on ecosystems; and we have high confidence for climate impacts on agriculture (reduced to some degree, compared to our level of confidence about ecosystems, by uncertainty about the efficacy and implementation of adaptation options). Confidence in fisheries changes is high since confidence in both ocean warming and fish sensitivity to temperature is high.

References :

• Projected change in climate thresholds in the Northeastern U.S.: implications for crops, pests, livestock, and farmers (41452674)
• Responding to Climate Change in New York State: The ClimAID Integrated Assessment for Effective Climate Change Adaptation in New York State (95ba9f76)
• Responding to Climate Change in New York State: The ClimAID Integrated Assessment for Effective Climate Change Adaptation in New York State (bdc2678b)
• Climate Impacts on Agriculture: Implications for Crop Production (a2704ef3)
• Potential climate-change impacts on the Chesapeake Bay (11bd4ad9)
• Climate Change in the Northeast: A Sourcebook. Draft Technical Input Report prepared for the U.S. National Climate Assessment (5f2be58e)
• Global Climate Change Impacts in the United States (e251f590)
• Responding to Climate Change in New York State: The ClimAID Integrated Assessment for Effective Climate Change Adaptation in New York State (4c695b45)