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C limate refers to the average weather pattern of a par- ticular area. Weather is the state of the atmosphere of a particular region. The fac- tors that contribute to the weather of a given place are rainfall, temperature, air pressure, and humidity. Weather changes every day. Climate change, however, is a much more complex phe- nomenon, with great consequences on ecology. The rise in global temperatures over the decades has proved that cli- mate is indeed changing. Much of this change is attributed to various human activities. Adapting to climate change is not always easy, but there is no al- ternative than to adjust. To prevent further damage, people need to adopt a more responsible attitude toward nature and restrict the activities that harm it in the longer run. INTRODUCTION

The Younger Dryas About 14,500 years ago, the earth’s tem- perature began to change from a glacial state to a warmer state (interglacial). How- ever, the climate again changed to glacial conditions for a brief period. This period is called the Younger Dryas. It lasted for about 1,200 to 1,300 years and occurred around 12,800 to 11,500 years ago. 8.2 Kiloyear Event The earth’s temperature started rising at the beginning of the Holocene Period. However, around 8,200 years ago, the climate changed abruptly and the planet cooled down. This lasted for about two to four centuries. There- after, the temperatures returned to the pre- vious state. Scientists called this abrupt cool- ing of earth the 8.2 K event. Climate in the Past About 2.7 billion years ago, the earth expe- rienced its first glacial period known as the first ice age. During this period, everything was covered in thick ice sheets. Then the planet warmed up until another ice age be- gan about 850 million years ago. The last ice age ended about 11,000 years ago, be- ginning the present period known as the Holocene Epoch.

CLIMATE CHANGE: Problems and Progress

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