ENVIRONMENTAL ISSUE

Global Warming

Abstract

The purpose of the paper is to discuss the phenomenon of global warming and the impact of human activities on climate change. There are a number of impacts of human activities on the environment.

Global Warming

Introduction

Global warming has been prevailing for many decades, but the effects have been intensified over the past few years. Scientists have begun to say that humans and their activities are a huge contributing factor to global warming. The changes to the Earth began in the polar regions and spread to all other areas. Since the 1970s, the occurrence of global warming is attributed to human activities.

Discussion

Over the past decade, Earth's climate has shifted many times due to a slight change in the planet's orbit, changes in solar activity and volcanic eruptions near the equator. About forty years ago, researchers began thinking that also influenced the climate, but they lacked the tools to test their ideas. Now, the evidence has become increasingly clear that human beings are altering Earth's atmosphere and oceans.

The technological advancements are making it easier to understand the causes of climate change. Thanks to a new generation of supercomputers developed in the past decade, scientists have confirmed that most global warming over the past 30 years stemmed from an unnatural build-up of greenhouse gases, says Gerald Meehl, senior scientist at NCAR in Boulder. Worldwide, the basic questions - such as, 'Is global warming happening and are humans contributing to it by burning fossil fuels?' - have been answered 'yes.' It is only in the United States that there is much debate over the phenomenon. In 2003, Naomi Oreskes, science historian at the University of California San Diego, analyzed 928 abstracts from scientific journals published from 1993 to 2003. Among the abstracts, there was not even one that disputed the fact that human activities are contributing to global warming.

Today scientists are trying to resolve other crucial questions: How quickly will the climate change, when will it reach a tipping point, what will be the consequences and is there anything we can do about it? Worldwide, the biggest worry involves the oceans as the sea levels are seen to rise. Water takes longer to heat than does air, and it takes even longer to cool. Now that the oceans are warmer (and more acidic from carbon dioxide) they will need a very long time to rebalance. The oceans make climate change a multigenerational problem. This can be seen as matter expands during times of heat and the sea and ocean levels rise due to this warmth. It has been seen that there was a 6- to 8- inch rise in ocean levels in the 20th century.

On top of that, scientists say an unusual amount of fresh water has started pouring into the oceans as polar and glacier ice melts. An in- depth study, done over several years by University of Colorado scientists, found that Antarctica is losing its ice at a rate of 36 cubic miles per ...