CLIMATE CHANGE? What’s this Noise All About?
Climate Change refers to any significant change in the measures of climate lasting for an extended period of time. In order words, Climate Change includes major changes in temperature, precipitation, or wind patterns among other effects, that occur over several decades or longer. Current global concern is focused on Climate Change resulting from human activity and specifically from the release of carbon di oxide and other greenhouse gases to the atmosphere. The burning of fossil fuels, clearing of forests and certain other human activities are major sources of greenhouse gas emissions.
The Earth’s climate is changing, and people’s activities are the main cause.
Our world is always changing. Look out your window long enough, and you might see the weather change. Look even longer, and you’ll see the seasons change. The Earth’s climate is changing, too, but in ways that you can’t easily see.
The Earth is getting warmer because people are adding heat-trapping gases to the atmosphere, mainly by burning fossil fuels. These gases are called greenhouse gases. Warmer temperatures are causing other changes around the world, such as melting glaciers and stronger storms. These changes are happening because the Earth’s air, water, and land are all linked to the climate. The Earth’s climate has changed before, but this time is different. People are causing these changes, which are bigger and happening faster than any climate changes that modern society has ever seen before.
Climate refers to the average weather conditions in a certain place over many years. The average climate around the world is called global climate.
When scientists talk about global climate change, they’re talking about the global climate and a pattern of change that’s happening over many years. One of the most important trends that scientists look at is the average temperature of the Earth, which has been increasing for many years. This is called global warming.
Rising global temperatures lead to other changes around the world such as stronger hurricanes, melting ice, and the loss of wildlife habitats. That’s because the Earth’s air, water, and land are all related to one another and to the climate. This means a change in one place can lead to other changes somewhere else. For example, when air temperatures rise, the oceans absorb more heat from the atmosphere and become warmer. Warmer oceans, in turn, can cause stronger storms.
Today’s Climate Change
More than 100 years ago, people around the world started burning large amounts of coal, oil, and natural gas to power their homes, factories, and vehicles.
Today, most of the world relies on these fossil fuels for their energy needs. Burning fossil fuels releases carbon dioxide, a heat-trapping gas, into the atmosphere, which is the main reason why the climate is changing.
Heat-trapping gases are also called greenhouse gases. They exist naturally in the atmosphere, where they help keep the Earth warm enough for plants and animals to live. But people are adding extra greenhouse gases to the atmosphere. These extra gases are causing the Earth to get warmer, setting off all sorts of other changes around the world—on land, in the oceans, and in the atmosphere. And these changes affect people, plants, and animals in many ways.
History of Climate Change
The Earth’s Climate in the Past
Scientists look in many places to find clues about climate change. For example, they examine historical records; collect measurements; and observe trends in temperature, weather patterns, sea level, and other features of the environment.
Today’s climate change is different from past climate change in several important ways:
- Natural causes are not responsible. None of the natural causes of climate change, including variations in the sun’s energy and the Earth’s orbit, can fully explain the climate changes we are seeing today.
- People’s activities are the main cause. By burning lots of fossil fuels like coal, oil, and natural gas, people are overloading the atmosphere with carbon dioxide and adding to the greenhouse effect. People are also adding other heat–trapping greenhouse gases, such as methane and nitrous oxide, to the atmosphere.
- Greenhouse gases are at record levels in the atmosphere. For hundreds of thousands of years, the concentration of carbon dioxide in the atmosphere stayed between 200 and 300 parts per million. Today, it’s up to nearly 400 parts per million, and the amount is still rising. Along with other greenhouse gases, this extra carbon dioxide is trapping heat and causing the climate to change.
The Earth was formed about 4.5 billion years ago—that’s a very long time ago! It’s difficult to say exactly what the Earth’s daily weather was like in any particular place on any particular day thousands or millions of years ago. But we know a lot about what the Earth’s climate was like way back then because of clues that remain in rocks, ice, trees, corals, and fossils.
These clues tell us that the Earth’s climate has changed many times before. There have been times when most of the planet was covered in ice, and there have also been much warmer periods. Over at least the last 650,000 years, temperatures and carbon dioxide levels in the atmosphere have increased and decreased in a cyclical pattern. Can you see this pattern in the graph below?
EPA’s Climate Change Indicators (2014)
The concept and science of Climate change by Glory Oguegbu