Could Climate Change Cause Deadly Epidemics?
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The effects of global warming are frequently projected decades into the future, but two recent reports -- one from theU.S. Global Change Research Program
and the otherfrom the U.N.
-- put into sharp focus visible consequences of our warming planet. An increase in temperature, extreme weather, loss of ice and rising sea level are just a few of changes we can measure right now. Let's take a look at some of the most concerning trends.BLOG: War Of The Words: Climate Change Or Global Warming?
Glaciers are shrinking worldwide and permafrost is thawing in high-latitude and high-elevation areas, reports this year's Fifth Assessment Report from the Intergovernmental Panel on Climate Change.BLOG: Dire Outlook For Climate Impacts, New Report Says
Only a few extinctions are attributed to climate change, reports the IPCC, but climate change that occurred much more slowly, over millions of years, caused major ecosystem shifts and species extinctions. Land and sea animals are changing their geographic ranges and migratory patterns due to climate change.NEWS: Climate Change: Why Haven't We Done More?
Sea level around the world has increased by about 8 inches since 1880, reports the 2014 National Climate Assessment, which projects a 1 to 4 foot rise by the end of the century.PHOTOS: Craziest Environmental Ideas (That Could Work)
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Excess CO2 is dissolving in the ocean and decreasing the pH of seawater. The ocean is about 30 percent more acidic than it was in pre-industrial times. More acidity in the oceans makes it harder for animals to form calcium carbonate shells and skeletons and erodes coral reefs.11 Health Threats from Climate Change
The probability of a Sandy-like storm deluging New York, New Jersey and other parts of the East Coast has nearly doubled compared to 1950, according to the American Meteorological Society. Even weaker storms will be more damaging now than they were 10 years ago because of rising sea levels. Superstorm Sandy cost the nation $65 billion, according to the 2014 National Climate Assessment, and 2012's Hurricane Isaac cost $2.3 billion.
The global sea level rises along with the temperature for two major reasons. For one, heat causes water to expand, which causes the existing water to take up more space and encroach on the coast. At the same time, ice at the poles and in glaciers melts and increases the amount of water in the oceans.PHOTOS: Melting Glaciers
Across the United States, heavy downpours are on the rise, especially in the Northeast and Midwest. Increases in extreme precipitation are expected for all U.S. regions, reports the 2014 National Climate Assessment.NEWS: Shrinking Greenland Glacier Smashes Speed Record
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The most recent IPCC report states with "very high confidence" that current climate-related extremes like heat waves, droughts, floods, cyclones and wildfires are showing that countries around the world, at all development levels, are significantly unprepared. The American Meteorological Society estimates that approximately 35 percent of the extreme heat in the eastern United States between March and May 2012 resulted from human activities' effects on climate. The AMS warned that deadly heat waves will become four times more likely in the north-central and northeastern United States as the planet continues to warm.NASA: Global Warming Goes On
If people aren’t as concerned about climate change as they should be, one reason may be that the gradual rise of temperatures and ocean waters seems to give us plenty of time to take mitigating measures, such as seawalls to protect coastal cities and genetically-engineered crops that would be able to flourish in the altered environment. It’s harder to understand that climate change may endanger us in other ways that will be more difficult to combat. For example, it may cause a slew of deadly diseases, which are now seen mostly in poorer regions in the tropics, to spread to developed nations in temperate zones.
The latest concern: A newly-published study in BMC Public Health looked at dengue fever, a virus spread by mosquitoes that sickens 50 million people and kills about 12,000 people worldwide each year, mostly in tropical areas.
The researchers found that dengue eventually could become a significant health problem in parts of Europe, including Mediterranean and Adriatic coastal areas that are popular with tourists. Europe is becoming hotter and more humid, conditions that foster the growth of the mosquitoes.
The researchers studied data from Mexico about the occurrence of dengue fever and the effect of climate variables such as temperature, humidity and rainfall, as well as socioeconomic factors, such as population density and income, on the spread of the disease. They then used that data to model the infection rate in various regions of Europe over the next century. In some places, they predicted that rate of dengue fever cases will quintuple, to up to 10 cases per 100,000 inhabitants.
Almost all of the excess risk will fall on the coastal areas of the Mediterranean and Adriatic seas and the northeastern part of Italy, particularly the Po Valley, University of East Anglia medical school professor Paul Hunter said in a press release.
That comes after a 2013 study warned that people in the United States are also at risk from dengue due to climate change. Traditionally, America has only had a few hundred reported cases of dengue each year, usually involving international travelers. But the Natural Resources Defense Council says that the mosquito that transmits dengue now is found in 28 states.
Another 2014 study found that climate change may be increasing the spread of Lyme disease.