National Climate Assessment


Geographical coverage

Geographical scale of the assessment National,Sub-national
Country or countries covered United States
Any other necessary information or explanation for identifying the location of the assessment, including site or region name

In addition to national scale, eight sub-regions were evaluated along with two biogeographical units; the oceans surrounding US coasts, and the US coastline itself as a separate entity.

Conceptual framework, methodology and scope

Assessment objectives

As per US law, the report analyzes the effects of global change on the natural environment, agriculture, energy production and use, land and water resources, transportation, human health and welfare, human social systems, and biological diversity; and analyzes current trends in global change, both human-induced and natural, and projects major trends for the subsequent 25 to 100 years. This report additionally focuses on the interactions among several sectors at the national level and assesses key impacts on the regions of the U.S.: Northeast, Southeast and Caribbean, Midwest, Great Plains, Southwest, Northwest, Alaska and the Arctic, Hawai‘i and the Pacific Islands; as well as coastal areas, oceans, and marine resources. Finally, this report explicitly assesses the current state of adaptation, mitigation, and decision support activities in the U.S.

Mandate for the assessment

The U.S. Global Change Research Act of 1990 (Title 15 USC Sec 2921 2012) available at

Conceptual framework and/or methodology used for the assessment

Other (please specify)

The NCA conducted a series of workshops whose reports detail the elements of the framework and methodology. These were coalesced into a single strategy framework.

URL or copy of conceptual framework developed or adapted

The overall strategy can be downloaded at and the various reports at .

System(s) assessed

  • The NCA Long-Term Process
  • Our Changing Climate
  • Decision Support, Mitigation, and Adaptation
  • Research Agenda for Climate Change Science
  • Sectors and sectoral cross-cuts: Water resources, Energy supply and use, Transportation, Agriculture, Forestry, Ecosystems and biodiversity, Human health, Water, energy, and land use, Urban systems, infrastructure, and vulnerability, Tribal, indigenous, and native lands and resources, Land use and land cover change, Rural communities, Biogeochemical cycles
  • Regions and biogeographical cross-cuts: Northeast, Southeast and US-Affiliated Caribbean, Midwest, Great Plains, Southwest, Northwest, Alaska and the Arctic, Hawai‘i and US-Affiliated Pacific Islands, Oceans and marine resources, Coastal zone, development, and ecosystems

Species groups assessed

Ecosystem services/functions assessed


  • Food
  • Water
  • Timber/fibres
  • Genetic resources
  • Medicinal resources
  • Ornamental resources
  • Energy/fuel


  • Air quality
  • Climate regulation
  • Moderation of extreme events
  • Regulation of water flows
  • Regulation of water quality
  • Waste treatment
  • Erosion prevention
  • Pollination
  • Pest and disease control

Supporting Services/Functions

  • Habitat maintenance
  • Nutrient cycling
  • Soil formation and fertility
  • Primary production

Cultural Services

  • Recreation and tourism
  • Spiritual
  • inspiration and cognitive development

Scope of assessment includes

Drivers of change in systems and services


Impacts of change in services on human well-being


Options for responding/interventions to the trends observed


Explicit consideration of the role of biodiversity in the systems and services covered by the assessment


Timing of the assessment

Year assessment started


Year assessment finished

If ongoing, year assessment is anticipated to finish


Periodicity of assessment

Assessment outputs


Reports are available at

Communication materials (e.g. brochure, presentations, posters, audio-visual media)

Journal publications

Training materials

Other documents/outputs

Tools and processes

Tools and approaches used in the assessment

  • Modelling
  • Trade-off analysis
  • Geospatial analysis
  • Indicators
  • Scenarios
  • Economic valuation
  • Social (non-monetary) valuation

Process used for stakeholder engagement in the assessment process and which component

A broad range of workshops and stakeholder meetings took place during the building phase of the report. Chapter author teams of over 240 authors total then met to draft chapters. The draft report is available at and comments sought from the public over a 3 month period. Additional stakeholder meetings across the country, presentations and workshops at professional society meetings, NGOs and governmental bodies at all scales occurred and continue during the entire 4 year process leading to the report.

Key stakeholder groups engaged

Extensive outreach efforts via a network of partners with their own stakeholder networks were engaged. Groups ranged from NGOs, academic organizations, private industry, tribal and other governmental groups.

The number of people directly involved in the assessment process

More than 1000

Incorporation of scientific and other types of knowledge

  • Scientific information only
  • Resource experts (e.g. foresters etc)
  • Traditional/local knowledge
  • Citizen science

Supporting documentation for specific approaches, methodology or criteria developed and/or used to integrate knowledge systems into the assessment

Assessment reports peer reviewed



Accessibility of data used in assessment

Data underlying the report graphics will be accessible online when the report is available electronically.

Policy impact

Impacts the assessment has had on policy and/or decision making, as evidenced through policy references and actions

Independent or other review on policy impact of the assessment


Lessons learnt for future assessments from these reviews

Capacity building

Capacity building needs identified during the assessment

Actions taken by the assessment to build capacity

Fellowships/exchanges/secondments/mentoring programmes, Network and sharing experiences, Access to funding, Sharing of data/repatriation of data, Workshops, Developing/promoting and providing access to support tools, Formal training, Communication and awareness raising

How have gaps in capacity been communicated to the different stakeholders

Knowledge generation

Gaps in knowledge identified from the assessment

How gaps in knowledge have been communicated to the different stakeholders

Additional relevant information