What We Face – Climate Threats

Global warming has increased rapidly in recent years. Warmer air absorbs more moisture, resulting in both droughts and floods. Higher temperatures also increase risks to humans and other species, and cause migrations of species, e.g. Maine lobster populations moving northward in search of cooler waters. 



1. Communities
Climate change creates new risks and exacerbates existing vulnerabilities in communities across the United States, presenting growing challenges to human health and safety, quality of life, and the rate of economic growth.

2. Economy
Without substantial and sustained global mitigation and regional adaptation efforts, climate change is expected to cause growing losses to American infrastructure and property and impede the rate of economic growth over this century.

3. Interconnected Impacts
Climate change affects the natural, built, and social systems we rely on individually and through their connections to one another. These interconnected systems are increasingly vulnerable to cascading impacts that are often difficult to predict, threatening essential services within and beyond the Nation’s borders.

4. Actions to Reduce Risks
Communities, governments, and businesses are working to reduce risks from and costs associated with climate change by taking action to lower greenhouse gas emissions and implement adaptation strategies. While mitigation and  adaptation efforts have expanded substantially in the last four years, they do not yet approach the scale considered necessary to avoid substantial damages to the economy, environment, and human health over the coming decades.

5. Water
The quality and quantity of water available for use by people and ecosystems across the country are being affected by climate change, increasing risks and costs to agriculture, energy production, industry, recreation, and the environment. . Health

Impacts from climate change on extreme weather and climate-related events, air quality, and the transmission of disease through insects and pests, food, and water increasingly threaten the health and well-being of the American people,  particularly populations that are already vulnerable.

7. Indigenous Peoples
Climate change increasingly threatens Indigenous communities’ livelihoods, economies, health, and cultural identities by disrupting interconnected social, physical, and ecological systems. 

8. Ecosystems and Ecosystem Services

Ecosystems and the benefits they provide to society are being altered by climate change, and these impacts are projected to continue. Without substantial and sustained reductions in global greenhouse gas emissions, transformative impacts  on some ecosystems will occur; some coral reef and sea ice ecosystems are already experiencing such transformational changes.

9. Agriculture and Food
Rising temperatures, extreme heat, drought, wildfire on rangelands, and heavy downpours are expected to increasingly disrupt agricultural productivity in the United States. Expected increases in challenges to livestock health, declines in crop  Yields and quality, and changes in extreme events in the United States and abroad threaten rural livelihoods, sustainable food security, and  price stability.

10. Infrastructure

Our Nation’s aging and deteriorating infrastructure is further stressed by increases in heavy precipitation events, coastal flooding, heat, wildfires, and other extreme events, as well as changes  to average precipitation and temperature. Without adaptation, climate change will continue to degrade infrastructure performance over the rest of the century, with the potential for cascading impacts that threaten our economy, national security, essential services, and health and well-being.


A new study categorizes climate feedback loops and the possibility they could push the climate past planetary tipping points.

Recent climate projections may be underestimating the pace of global warming in an atmosphere damaged by greenhouse gas emissions, because the interaction of powerful climate feedback loops that can accelerate warming are not well-represented in key climate models, an international team of scientists concluded in a study published today in the journal One Earth. Their findings suggest that efforts to reduce emissions require even more urgency to avoid worst-case climate outcomes, the team reported.

“If amplifying feedbacks are strong enough, the result is likely tragic climate change moving beyond anything humans can control,” said co-author Bill Ripple, an ecologist at Oregon State University, and co-founder of the Alliance of World Scientists, which has 26,000 members in 180 countries urging decisive implementation of policies to curb global warming and meet the commitments governments made under the 2015 Paris Agreement

“We would like to see an IPCC special report that focuses on the many risky climate feedbacks and the possible acceleration towards planetary tipping points,” he said. “It’s important to understand the most optimistic estimates, but we also need to be informed of potential worst-case scenarios.”




Climate Feedback Loop Interactions