climate change

Climate Change

Jiangzhenghui Southern New Hampshire University

1 Introduction

Is human activity a substantial cause of climate change? Since the early 20th century, earth's mean surface temperature has increased by about 0.8 °C (1.4 °F), with about two-thirds of the increase occurring since 1980[1]. Due to the temperature becomes higher, the related changes has varied from region to region around the globe.

The impacts of global warming include a rise in sea levels and a change in the amount and pattern of precipitation, as well a probable expansion of subtropical deserts. The strongest effects of global warming is in the Arctic and would be associated with the continuing retreat of glaciers, permafrost and sea ice. For example, warming would be more appropriate for pathogens breeding, the incidence of malaria, Lyme disease,West Nile fever and other infectious diseases continue to increase. Extreme weather will make floods more frequently, which will affect more than one regions' safe drinking and weaken the natural self-cleaning ability. These negative impacts of climate change is the most serious in the Indian Ocean and the Pacific Rim as well as the Sahara desert in the hinterland of the least developing African countries. Further, scientists estimate that the earth's average temperature will rise by 1.4 ℃ to 5.8 ℃. In short, the global climate change will greatly harm to human health, the destruction of ecosystems, and thus bring about huge economic losses to society as a whole.

Many people argued that wether is human activity a substantial cause of global climate change the human or not. Even some people think that global warming is a fraud, they contend that our forests and oceans are capable of absorbing these small increases, and that 20th century warming has resulted from natural processes including fluctuations in the sun's heat and ocean currents. They say that global climate change is based on bunk science and scare tactics. However, global warming has actually happened. So it is agreed that greenhouse gas levels are rising due to human activities such as burning fossil fuels and deforestation which are causing significant climate changes.This will be proven by analysing three reasons. The first reason is that human activities produce CO2 is warming the earth is warming the earth. The second is that Human release greenhouse cannot be balanced by nature and the

third is many organizations believe that human activity is a substantial cause of global climate change.

2 The reasons of why human activity is a substantial cause of global climate change

2.1 Human activities produce CO2 is warming the earth

Figure1 The relative importance of these gases

A greenhouse gas (sometimes abbreviated GHG) is a gas(include water vapour, carbon dioxide, methane, nitrous oxide, and ozone) in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect[2]. Greenhouse gases greatly affect the temperature of the Earth. Some people believe that rising temperatures are caused primarily by water vapor, not by CO2,which concentrations in the atmosphere are driven by natural storm systems and ocean currents. However, the role of carbon dioxide accounts for about half of the total greenhouse effect which is shown in Figure1[3].Human-produced CO2 is warming the earth, not natural CO2 released from the ocean and other "carbon sinks." CO2from fossil fuel combustion has a specific isotopic ratio [4] that is different from CO2 released by natural "carbon sinks." 20th century measurements of CO2 isotope ratios in the atmosphere confirm that the rise results from human activities, not natural processes[5] .