Issues: Global Warming

The Consequences of Global Warming
On Weather Patterns

Higher temperatures could lead to increased droughts and wildfires, heavier rainfall and a greater number of Category 4 and 5 hurricanes.

More Powerful and Dangerous Hurricanes
Warmer water in the oceans pumps more energy into tropical storms, making them stronger and potentially more destructive.

Warning signs today:


• The number of category 4 and 5 storms has greatly increased over the past 35 years, along with ocean temperature.



• The 2005 Atlantic hurricane season was the most active Atlantic hurricane season in recorded history, with a record 27 named storms, of which 15 became hurricanes. Seven of the hurricanes strengthened into major storms, five became Category 4 hurricanes and a record four reached Category 5 strength.



• Hurricane Katrina of August 2005 was the costliest and one of the deadliest hurricanes in U.S. history.

Drought and Wildfire
Warmer temperatures could increase the probability of drought. Greater evaporation, particularly during summer and fall, could exacerbate drought conditions and increase the risk of wildfires.

Warning signs today:


• The 1999-2002 national drought was one of the three most extensive droughts in the last 40 years.



• Warming may have lead to the increased drought frequency that the West has experienced over the last 30 years.



• The 2006 wildland fire season set new records in both the number of reported fires as well as acres burned. Close to 100,000 fires were reported and nearly 10 million acres burned, 125 percent above the 10-year average.



• Firefighting expenditures have consistently totaled upwards of $1 billion per year.

Intense Rainstorms
Warmer temperatures increase the energy of the climatic system and can lead to heavier rainfall in some areas.

Warning signs today:


• National annual precipitation has increased between 5 and 10 percent since the early 20th century, largely the result of heavy downpours.



• The Intergovernmental Panel on Climate Change reports that intense rain events have increased in frequency during the last 50 years and human-induced global warming most likely contributed to the trend.



• According to the National Oceanic and Atmospheric Administration, the Northeast region had its wettest summer on record in 2006, exceeding the previous record by more than 1 inch.

Find out more about the consequences of global warming on:
Weather patterns | Health | Wildlife | Glaciers & sea levels

» Consequences main page

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Photo credits: hurricane: Photodisc; wildfire: Corbis; flood: iStock.