Climate change for beginners

 You’ve heard the terms “global warming”, “climate change” and “greenhouse effect”, among many other environment related terms, but what exactly do they mean? Here are some basics to help you understand why we are in a crisis.

The Earth gets its heat from the sun. However, the heat the Earth absorbs directly from the sun is not enough for our survival, since most of it radiates back into the atmosphere. It is estimated that the Earths’ temperatures would be about 33C/ 59F degrees cooler. So where does the rest of the heat come from?

Surrounding the Earth in the atmosphere are gases known as “greenhouse” gases. These gases trap some the heat that radiates from the Earth, keeping them around the Earth rather than allowing them to escape into space, providing us with the additional heat needed to survive. The higher the greenhouse gas concentration in the atmosphere, the more heat gets trapped to warm the Earth. This is what is referred to as the “greenhouse effect”. Greenhouse gases include water vapor, carbon dioxide (CO2), methane (CH4), and ozone (O3).

Greenhouse gas levels have fluctuated over the Earth’s history, but they have been reasonably constant for the past few thousand years, until recently. Since the Industrial Revolution of the 18th and 19th centuries, the amount of greenhouse gases in the atmosphere has increased, believed to be due to human activity- mainly the use of fossil fuels in cars, factories, and to produce electricity. As a result, temperatures have risen at much faster rates since. In fact, eleven of the twelve hottest years since thermometer readings became available occurred between 1995 and 2006. This abnormal rise in temperatures is known as “global warming”. The concentration of CO2, for example, has increased by 36% since the 1700s, while methane has increased by 148%. Most of the increase, in fact, has occurred only in the past few decades. Changes this great have historically happened over thousands of years, but are now happening within decades.

The burning of fossil fuels, such as coal and oil, has produced most of the increase in CO2. The rest of the increase is largely due to deforestation. Deforestation is the large scale cutting down of trees to make paper, building materials, provide flatlands for cattle grazing, population expansion, mining and oil extraction, among other purposes. Plants do us a service by absorbing CO2, reducing the amount that enters into the atmosphere as a greenhouse gas. Consequently, eliminating plants increases the amount of CO2 into the atmosphere.

As scientists have been improving their understanding of global warming, the term “climate change” has been found to be more accurate, because global warming leads to various climate changes. With the increase in temperature, winds and ocean currents move heat around in ways that can warm some areas and cool others. Changes in temperature also change the average amount of rain and snowfall.

So why is climate change a problem?

Climate change is problem for many reasons. First, the rapid changes in climate make it difficult for some living things to adapt. Plants and animals survive under certain climate conditions, but with the current changes, some species are having a hard time growing and living where they have been for thousands of years, while some are even becoming endangered. This not only reduces the richness of wildlife on Earth, but disrupts food chains and ecosystems, and may impact humans in areas where the crops and animals they depend on for food are decreasing.

In addition, even an increase in temperature of just a few degrees can set off a series of changes that cause weather to become more extreme, meaning more intense storms, rain, and longer droughts, which makes survival more difficult for all living things. For example, the increase in temperatures is causing ice sheets on Earth to melt, in areas such as Antarctica and Greenland. This affects animals, such as polar bears, which are already declining in number due to their shrinking habitat. Also, the melting of the ice sheets causes sea levels to rise significantly, putting coastal areas at high risk for flooding. Islands are particularly at risk for not only flooding, but significant or complete submersion under water.

Is Egypt at risk?

Egypt is highly vulnerable to climate change. Millions of Egyptians could be forced to migrate as a result of climate change, possibly within the next few decades. Egypt’s coastal zones, home to more than 40 per cent of the population, will be hit hardest. As the sea-level rises and coastal zones become submerged under water, millions will be forced to move. The salt water from the rising Mediterranean Sea is seeping into the fresh water of the Nile- the only source of fresh water in Egypt, and the surrounding soil, which will be detrimental to agriculture, the livelihoods of farmers, and Egypt’s economy. The large movement of people as a result of flooding and abandoning of agricultural land into urban areas, eco-refugees, are likely to fuel social tensions.

It is clear that climate change is both real and dangerous. If we do not change our policies, priorities and habits, the risk for climate catastrophes will continue to increase, which can potentially lead to economic and social disasters. It is time that tackling climate change be an individual, national, and global priority.

BM