Why should I be concerned about climate change? - FOX 29 News Philadelphia | WTXF-TV

Why should I be concerned about climate change?

Source: NASA

Global climate change has already had observable effects on the environment. Glaciers have shrunk, ice on rivers and lakes is breaking up earlier, plant and animal ranges have shifted and trees are flowering sooner.

Effects that scientists had predicted in the past would result from global climate change are now occurring: loss of sea ice, accelerated sea level rise and longer, more intense heat waves.

Scientists have high confidence that global temperatures will continue to rise for decades to come, largely due to greenhouse gasses produced by human activities. The Intergovernmental Panel on Climate Change (IPCC), which includes more than 1,300 scientists from the United States and other countries, forecasts a temperature rise of 2.5 to 10 degrees Fahrenheit over the next century.

According to the IPCC, the extent of climate change effects on individual regions will vary over time and with the ability of different societal and environmental systems to mitigate or adapt to change.

The IPCC predicts that increases in global mean temperature of less than 1.8 to 5.4 degrees Fahrenheit (1 to 3 degrees Celsius) above 1990 levels will produce beneficial impacts in some regions and harmful ones in others. Net annual costs will increase over time as global temperatures increase.

"Taken as a whole," the IPCC states, "the range of published evidence indicates that the net damage costs of climate change are likely to be significant and to increase over time."

Below are some of the regional impacts of global change forecast by the IPCC:

  • North America: Decreasing snowpack in the western mountains; 5-20 percent increase in yields of rain-fed agriculture in some regions; increased frequency, intensity and duration of heat waves in cities that currently experience them.
  • Latin America: Gradual replacement of tropical forest by savannah in eastern Amazonia; risk of significant biodiversity loss through species extinction in many tropical areas; significant changes in water availability for human consumption, agriculture and energy generation.
  • Europe: Increased risk of inland flash floods; more frequent coastal flooding and increased erosion from storms and sea level rise; glacial retreat in mountainous areas; reduced snow cover and winter tourism; extensive species losses; reductions of crop productivity in southern Europe.
  • Africa: By 2020, between 75 and 250 million people are projected to be exposed to increased water stress; yields from rain-fed agriculture could be reduced by up to 50 percent in some regions by 2020; agricultural production, including access to food, may be severely compromised.
  • Asia: Freshwater availability projected to decrease in Central, South, East and Southeast Asia by the 2050s; coastal areas will be at risk due to increased flooding; death rate from disease associated with floods and droughts expected to rise in some regions.

Global Climate Change: Recent Impacts

Phenomena Likelihood that trend occurred in late 20th century
Cold days, cold nights and frost less frequent over land areas Very likely
More frequent hot days and nights Very likely
Heat waves more frequent over most land areas Likely
Increased incidence of extreme high sea level * Likely
Global area affected by drought has increased (since 1970s) Likely in some regions
Increase in intense tropical cyclone activity in North Atlantic (since 1970) Likely in some regions

* Excluding tsunamis, which are not due to climate change.

Global Climate Change: Future Trends

Phenomena Likelihood of trend
Contraction of snow cover areas, increased thaw in permafrost regions, decrease in sea ice extent Virtually certain
Increased frequency of hot extremes, heat waves and heavy precipitation Very likely to occur
Increase in tropical cyclone intensity Likely to occur
Precipitation increases in high latitudes Very likely to occur
Precipitation decreases in subtropical land regions Very likely to occur
Decreased water resources in many semi-arid areas, including western U.S. and Mediterranean basin High confidence

For more information, visit NASA's website on Climate Change.

*DISCLAIMER*: The information contained in or provided through this site section is intended for general consumer understanding and education only and is not intended to be and is not a substitute for professional advice. Use of this site section and any information contained on or provided through this site section is at your own risk and any information contained on or provided through this site section is provided on an "as is" basis without any representations or warranties.
Powered by WorldNow

WTXF-TV
330 Market Street
Philadelphia, PA 19106-2796

Phone: (215) 925-2929
Fax: (215) 982-5494

Didn't find what you were looking for?
All content © Copyright 2000 - 2014 Fox Television Stations, Inc. and Worldnow. All Rights Reserved.
Privacy Policy | New Terms of Service What's new | Ad Choices