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Carbon emissions are the primary driver of climate change, with carbon dioxide accounting for over 80 % of the U.S. greenhouse gases, according to the Environmental Protection Agency (EPA). The combustion of fossil fuels releases CO₂ and other greenhouse gases, trapping solar heat and raising global temperatures. These changes disrupt water supplies, alter weather patterns, shift crop growing seasons, and threaten coastal communities through rising sea levels.
CO₂ remains in the atmosphere for 50–200 years, meaning today's emissions will continue to warm the planet for decades. The EPA projects that climate change will increase water demand while shrinking supply. Adequate water is critical for public health, manufacturing, energy production, and food security. In some regions, warming will amplify rainfall, which can transport sediment and pollutants into drinking water. Rising seas will push saltwater into freshwater aquifers, heightening the need for desalination and advanced treatment.
NASA warns that global warming is linked to more wildfires, droughts, and tropical cyclones. In 2012, catastrophic storms cost the United States $1 billion in damage, and events like Hurricane Sandy (2012) and Typhoon Haiyan (2013) illustrate the growing frequency of high‑impact storms. Such events can devastate infrastructure, spread water‑borne diseases, and result in significant loss of life, often requiring international assistance for recovery.
Changing climate conditions alter the growing environments for many crops. The U.S. Global Change Research Program reports that rising temperatures in California’s Central Valley will drastically reduce yields of tomatoes, wheat, rice, maize, and sunflowers. Global crop shortages will push food prices higher, and wildlife that provide protein sources are forced to relocate to cooler, higher‑altitude or northern habitats.
Small temperature shifts can produce dramatic environmental effects. During the last ice age, temperatures were only 2.5–5 °C (5–9 °F) cooler than today, yet large parts of the United States were buried under ice. The Intergovernmental Panel on Climate Change (IPCC) projects a global temperature rise of about 1.5 °C (2.5 °F) over the next century, which will reshape shorelines. Sea levels along the mid‑Atlantic and Gulf Coasts have risen more than 20 cm (8 inches) in the past 50 years, threatening densely populated coastal zones.
