Floods, droughts, tornadoes and hurricanes; most would consider these forces of nature. For the last four hundred years, humans have been added to that list. “Because of our numbers and our technology, it now seems likely that we have begun altering the climate of our planet” (Karl 78). Nowhere is this more apparent than in the gradual but disastrous rise in the Earth’s temperature. The effects of global warming are as varied as the causes. Among them are: loss of habitat due to the melting of ice caps and tropical deforestation, increased danger due to extreme weather patterns, increases in disease and famine, and conflict over resources. This warming, which scientists predict will raise the average temperature of the planet by an additional three to seven degrees by the year 2100, will drastically change life on Earth.
Among the regions particularly vulnerable to warming are the polar ice caps. The icy terrain north of the Arctic Circle is the only place on Earth home to the polar bear. With the loss of more sea ice every year, the population of the polar bear dwindles, with an estimated two thirds of the population completely gone by 2050 (Walsh 50). The arctic ice also serves as a giant mirror, reflecting the sun’s rays back out into space and helping to keep the Earth cool. This rapid loss of ice in the Arctic is why scientists believe that all glaciers in Glacier National Park will be gone by 2030. The loss of these glaciers will also affect the water supply of the people dependent on it for drinking.
This melting of the ice caps, combined with the warming of the oceans will cause sea levels to rise. As water is heated, it gains volume, thus causing the existing water to take up more space. Add to this the billions of metric tons of water from once frozen continents and we will soon have a new standard for sea level. “One of the greatest concerns related to global warming is how far sea levels will rise if the vast continental ice sheets of Greenland and Antarctica begin to melt” (Smith 1489).
This rise in sea levels will affect millions of people living in coastal cities worldwide. “While a mere 2 per cent of the world’s land is less than 10 metres above the mid-tide sea level, it is home to most of the world’s population — 630 million and counting — and much valuable property and vital infrastructure” (Hansen 9). The new sea level would also threaten to destroy valuable habitats. “Half of all ducks in North America use endangered wetlands for breeding or as stopping places” on their migratory route (Seed 14).
The warming of the oceans themselves not only serves to increase the level of the waters on Earth, but will also affect our weather as well. “As the climate warms, scientists anticipate changes in tropical cyclone activity” (Karl 81). Tropical storms and hurricanes feed off warm rising air, and the warmer the oceans get, the more violent and numerous these storms will become. The summer of 2006 saw so many hurricanes that the National Hurricane Center ran out of names and began using Greek letters. Furthermore, all of the Earth’s weather is dependent on the currents of the oceans. The change in water temperature could also disrupt the currents that marine life depend on to replenish their food supply.
These dangers are further magnified by tropical deforestation. Trees serve the planet in that they help to regulate carbon dioxide. Through photosynthesis, trees intake carbon dioxide and create oxygen, thus helping to purify the air. Trees in the tropics are being removed “with more than one Tennessee’s worth of rainforest being slashed and burned each year” (Gore 23). Not only is this a profound loss to our planet’s natural defense system, these trees are being cleared to provide pasture for fast food beef. “One kilogramme of beef is responsible for more greenhouse gas emissions than a three-hour drive across the country while leaving all the lights on at home” (“Cows” 5). Deforestation for this reason serves only to accelerate the warming of our planet. Additionally, the loss of species is phenomenal. According to the biologist Tom Lovejoy “there are more species of birds in each square mile of the Amazon than exist in all of North America” (Gore 23).
The changes we are causing in our atmosphere will affect human health as well. “Poor air quality also contributes to breathing difficulties. Already, the country has seen a four-fold increase in the prevalence of asthma since 1980” (Wilson 154). Scientists predict we will see a rise in viruses such as malaria and West Nile and even more severe cases of poison ivy. As larger areas of our planet become warmer, they are more hospitable to viruses and the animals and insects that carry them. “Recent malaria outbreaks in the highlands of West Africa and elsewhere may also stem from climate change” (Fisher-Wilson 154). In the past, many virus particles died in cold weather. With the average temperature increasing, we see that these viruses now have a wider range of ambient temperatures in which to cultivate. “The World Health Organization (WHO) has estimated that warming and precipitation trends already claim at least 150,000 lives annually worldwide and that this number will climb to 300,000 annually by 2030” (Fisher-Wilson 153).
The risks to humans don’t stop there. As world resources become more scarce, people are likely to migrate as well, causing refugees to flee for clean water and more fertile soil. This could cause conflict over lack of resources. Already we engage in conflict over oil. Imagine if we had to go to war over fresh water or farmland. The human race has begun to impact our planet in ways that we previously couldn’t imagine. We must acknowledge that global warming is a threat to our wildlife, resources, and way of life.