Climate change means drastic and long-term effects like rising sea levels and the increased likelihood of extreme weather events. But across the world, we are already witnessing the consequences of a warming world.

In the U.S., climate change means that allergies are getting worse as pollen counts increase, and some of your favorite foods -- from apples to oysters to coffee and wine -- are also in jeopardy. Warmer winters in northern latitudes also mean worsening conditions for outdoor sports like hockey, dog sled racing and skiing. There is also increased pressure on an already fragile water supply.

On a global level, sea level rise poses an existential threat to low-lying nations in the Pacific, while in Africa, climate change is making droughts and deadly famines more likely.

Dramatic change is already evident in the Arctic. After record sea ice melt in 2012, NOAA research shows that the Arctic will see ice-free summers by 2050, if not within the next decade or two. It has been suggested that "what happens in the Arctic doesn’t stay in the Arctic," and melting there may contribute to more extreme weather at moderate latitudes.

Scientists are nearly unanimous in their findings that climate change is both real and manmade. Research has shown that current human activities, like the burning of fossil fuels, are inevitably going to cause atmospheric warming and sea level rise for at least another 1,000 years.

International leaders have stressed the imperative to address climate change and warned that the global development of low-carbon energy may be happening too slowly.

Learn about some of the most evident effects of climate change in the slideshow below.

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  • A Bumpier Ride?

    Researchers in Britain have found that <a href="http://www.bbc.co.uk/news/science-environment-22076055" target="_blank">climate change could cause increased turbulence</a> for transatlantic flights by between 10 and 40 percent by 2050. (ALEXANDER KLEIN/AFP/GettyImages)

  • Not A Drop To Drink

    A 2012 study from the U.S. Forest Service found that without "major adaptation efforts," parts of the U.S. are likely to see "<a href="http://www.treesearch.fs.fed.us/pubs/42363" target="_blank">substantial future water shortages</a>." Climate change, especially for the Southwest U.S., can both <a href="http://thinkprogress.org/climate/2013/02/25/1638541/study-climate-change-dry-up-us-reservoirs-lake-powell-lake-mead" target="_blank">increase water demand and decrease water supply</a>.

  • An International Tragedy

    Research by British government found that <a href="http://www.huffingtonpost.com/2013/03/15/somalia-famine-climate-change_n_2883088.html" target="_blank">climate change may have contributed to a famine in East Africa</a> that killed between 50,000 and 100,000 people in 2010 and 2011. At least 24 percent of the cause of a lack of major rains in 2011 can be attributed to man-made greenhouse gases, Met Office modeling showed. (TONY KARUMBA/AFP/Getty Images)

  • A Mighty Wind

    The <a href="http://www.guardian.co.uk/environment/2013/mar/25/frozen-spring-arctic-sea-ice-loss" target="_blank">dramatic and rapid loss of sea ice in recent years</a> has consequences beyond the Arctic. Scientists have found the melting shifts the position of the Jet Stream, bringing cold Arctic air further south and increasing the odds of intense snow storms and extreme spring weather.

  • An Itch You Can't Scratch

    Research indicates that increased levels of atmospheric carbon dioxide <a href="http://www.onearth.org/blog/poison-ivy-climate-change" target="_blank">result in larger poison ivy plants</a>. Even worse, climate change will mean that the plant's irritating oil will also get more potent.

  • Worsening Allergies

    The <a href="http://www.livescience.com/28320-climate-change-allergies.html" target="_blank">spring 2013 allergy season could be one of the worst ever</a>, thanks to climate change. Experts say that increased precipitation, along with an early spring, late-ending fall and higher levels of atmospheric carbon dioxide may bring more pollen from plants and increased mold and fungal growth.

  • Gators In The Yard

    North American alligators require a certain temperature range for survival and reproduction, traditionally limiting them to the southern U.S. <a href="http://www.slate.com/articles/health_and_science/animal_forecast/2013/02/alligators_in_virginia_climate_change_could_be_pushing_cold_blooded_species.single.html" target="_blank">But warming temperatures could open new turf</a> to gators with more sightings farther north.

  • Melting Blitz In South America

    High in the Peruvian Andes, parts of the world's largest tropical ice sheet have melted at an unbelievable pace. Scientists found that significant <a href="http://www.nytimes.com/2013/04/05/world/americas/1600-years-of-ice-in-perus-andes-melted-in-25-years-scientists-say.html" target="_blank">portions of the Quelccaya Ice Cap that took over 1,600 years to form have melted in only 25 years</a>. (Perito Moreno Glacier pictured)

  • Wine To Go?

    Along with other agricultural impacts, <a href="http://www.huffingtonpost.com/2013/04/08/climate-change-wine_n_3039673.html" target="_blank">climate change may have a dramatic effect on the world's most famous winemaking regions</a> in coming decades. Areas suitable for grape cultivation may shrink, and temperature changes may impact the signature taste of wines from certain regions.

  • Home Sweet Home

    Thanks to climate change, <a href="http://www.guardian.co.uk/sustainable-business/blog/polar-arctic-greenland-ice-climate-change" target="_blank">low-lying island nations may have to evacuate</a>, and sooner than previously expected. Melting of the Greenland and west Antarctic ice sheets has been underestimated, scientists say, and populations in countries like the Maldives, Kiribati, Tuvalu and others may need to move within a decade.

  • Trouble On The Ice

    Warmer winters in northern latitudes could mean <a href="http://www.cbc.ca/news/technology/story/2013/01/18/hamilton-climate-change-rinks.html" target="_blank">fewer days for outdoor hockey</a>. An online project called RinkWatch aims to collect data on the condition of outdoor winter ice rinks in Canada and the northern U.S. and educate people on the impacts of climate change.

  • A Damper On Your Raw Bar?

    Experts speculate that <a href="http://news.nationalgeographic.com/news/2010/08/100806-oyster-herpes-global-warming-climate-change-science/" target="_blank">warming oceans may have played a part in a strain of herpes</a> that has killed Pacific oysters in Europe in recent years.

  • The Color-Changing Bears

    As Arctic ice melts and polar bears see more of their habitat disappear, the <a href="http://www.huffingtonpost.ca/2013/03/14/polar-bears-turn-brown-climate-change_n_2878684.html" target="_blank">animals could lose their famous white coats</a>. Researchers have already witnessed polar bears hybridizing with their brown cousins, but note that it would take thousands of years from them to adapt themselves out of existence.

  • Less Time On The Chair Lift

    Climate change means warmer winters in northern latitudes and a shorter ski season. By 2039, <a href="http://www.nytimes.com/2012/12/13/us/climate-change-threatens-ski-industrys-livelihood.html" target="_blank">more than half of the Northeast's ski resorts</a> will not be able to maintain a 100-day season, according to the New York Times. Ski areas will be less likely to receive regular snowfall, and warmer daily low temperatures mean fewer opportunities for snowmaking.

  • Sour Apples

    Apples produced in one Himalayan state of India are already losing their taste and even turning sour, experts say. <a href="http://zeenews.india.com/news/eco-news/arunachal-apples-losing-taste-due-to-climate-chang_831169.html" target="_blank">Increased rainfall and erratic weather in the region mean less than ideal conditions</a> for famously-sweet Kashmiri apples.

  • A Tough Time For Mushers

    With climate change already impacting northern latitudes, <a href="http://www.nytimes.com/2013/02/06/sports/warm-weather-forces-changes-ahead-of-iditarod-race.html" target="_blank">warmer winters in Alaska could mean less than ideal conditions</a> for the famous Iditarod sled dog race. “It definitely has us concerned,” a musher and Iditarod spokeswoman who's already breeding dogs with thinner coats told The New York Times.

  • A Cold Cup Of Coffee

    <a href="http://news.nationalgeographic.com/news/2012/11/121108-climate-change-coffee-coffea-arabica-botanical-garden-science/" target="_blank">Climate change may dramatically shrink the area suitable for coffee cultivation</a> by the end of the century and cause the extinction of Arabica coffee plants in the wild. Starbucks has already declared that "<a href="http://www.starbucks.com/responsibility/environment/climate-change" target="_blank">Addressing climate change is a priority</a>."

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