Climate Matters•November 14, 2023
New National Climate Assessment
KEY CONCEPTS
On November 14, the U.S. Global Change Research Program released the Fifth National Climate Assessment (NCA5).
This major report, with hundreds of expert authors, reviews the latest science on climate change trends, impacts, and solutions across the U.S.
Learn what the NCA5 covers, what’s new since previous reports, and how to access and report on NCA5 findings for specific topics or regions.
KEY LINKS:
The NCA5 is freely available on the USGCRP website upon publication.
Stay up-to-date on NCA5’s release by subscribing to the USGCRP newsletter.
Learn more about the report including FAQs, timelines, and a chapter summary.
What’s the National Climate Assessment?
The National Climate Assessment (NCA) is an authoritative assessment of all aspects of climate science, with a focus on the United States.
A new NCA, mandated by Congress in the Global Change Research Act of 1990, is presented to the President and Congress every four years.
NCA reports assess the many ways that climate change affects the U.S. natural environment, agriculture, energy, land and water resources, human health, social systems, biodiversity, and much more.
Why do National Climate Assessments matter?
According to The White House, “the National Climate Assessment is the preeminent source of climate information for the United States, used by hundreds of thousands of people across the country and around the world. This report assesses the science of climate change, its impacts, and our options for reducing present and future risk.”
The NCA is used by communities, cities and states, the private sector (e.g., agriculture, energy), and the federal government to prepare for the current and future impacts of climate change in the U.S.
Because these reports are published approximately every four years, each installment is an up-to-date valuable resource for years into the future.
Who produces National Climate Assessments?
The U.S. Global Change Research Program (USGCRP) is responsible for producing NCA reports.
The USGCRP is made up of 14 federal departments and agencies that conduct or use research on global change and its impacts on society and nature. NOAA is the administrative agency for the upcoming NCA.
NCA reports don’t make policy recommendations or evaluate specific policies. They are peer-reviewed technical assessments, written by hundreds of scientists and other climate experts, that summarize the latest available knowledge.
Learn more about report authors and the drafting and review process here.
What does the Fifth National Climate Assessment cover?
The NCA5 process started in 2020. A draft opened for public comment and scientific review in the fall of 2022. During summer 2023, the NCA5 went through final revisions.
The previous installment, the Fourth National Climate Assessment, was released in 2017-2018 over two volumes:
Climate Science Special Report covered foundational climate science
Impacts, Risks, and Adaptation in the United States focused on impacts and future pathways.
NCA5 is a technical scientific assessment and does not make policy recommendations, consistent with all previous NCA reports.
The NCA5 has four major thematic sections:
Physical Science: reviewing past and projected future climate trends and changes in the Earth system
National Topics: assessing trends and impacts on 17 key topics including: water, energy, forests, biodiversity, coasts and oceans, cities, agriculture, air quality, health, economics, and more
Regions: summarizing current and future climate risks in ten U.S. regions, with a chapter for each: Northeast; Southeast; U.S. Caribbean; Midwest; Northern Great Plains; Southern Great Plains; Northwest; Southwest; Alaska; and Hawai‘i and U.S.-affiliated Pacific Islands
Responses: focusing on adaptation and mitigation options and scenarios for the U.S.
What’s new in the Fifth National Climate Assessment?
There are many exciting new developments in NCA5. Here are a few:
Social science and justice. Plans for NCA5 include new chapters that focus on economics and social systems and justice.
Focus features. A new set of “focus” features will explore emerging or cross-cutting topics: compound extremes, western wildfires, COVID-19 and climate change, risks to supply chains, and blue carbon.
Art x Climate. The NCA5 will feature visual art by 92 artists of all ages from across the U.S., the result of a first-ever open call for art to feature in an NCA.
Spanish translation. During the public comment period, a Spanish translation of the draft U.S. Caribbean chapter was made available for public comment. Details about Spanish versions of the full NCA5 are not yet available.
LOCAL STORY ANGLES
The NCA5 will assess different indicators of climate change in each major U.S. region. Climate change indicators are specific data or metrics that are linked to our warming climate. Long-term trends in climate indicators are evidence of the local effects of global change.
Climate Matters often features indicators of climate change. Here are a few recent examples for each region featured in the NCA5:
The Northeast is experiencing more heavy downpours, rapid ocean warming, and rising sea levels.
The Southeast faces more coastal flooding, damaging hurricane intensification, and more risky heat days.
The U.S. Caribbean is experiencing more ocean heatwaves, extreme heat boosted by climate change, and rising cooling demand with warming.
In the Midwest, growing and allergy seasons are expanding, tornado activity is rising, and Great Lakes ice coverage is shrinking.
In the Northern Great Plains, winter is warming fast, and fire weather and extreme rainfall occur more often.
The Southern Great Plains is experiencing extreme heat boosted by climate change, and rising cooling demand.
The Northwest is experiencing declining snowpack, more fire weather, and more humid heat.
In the Southwest, wildfire risk and rainfall extremes are all increasing while snowpack is declining.
In Alaska, ocean temperatures are rising and sea ice is declining.
In Hawaiʻi and U.S.-Affiliated Pacific Islands, warming oceans, rising sea levels, and increasing atmospheric CO2 concentrations measured on Mauna Loa are key climate indicators.
FIND EXPERTS
Submit a request to SciLine from the American Association for the Advancement of Science or to the Climate Data Concierge from Columbia University. These free services rapidly connect journalists to relevant scientific experts.
Browse maps of climate experts and services at regional NOAA, USDA, and Department of the Interior offices.
Explore databases such as 500 Women Scientists, BIPOC Climate and Energy Justice PhDs, and Diverse Sources to find and amplify diverse expert voices.
Reach out to your State Climate Office or the nearest Land-Grant University to connect with scientists, educators, and extension staff in your local area.