Climate Change

Warming oceans

What The Structure Deep Ocean

As ocean water warms up, it expands like the liquid in a thermometer, so sea levels rise by a small amount. But gauges like this show a much greater actual rise, indicating that melting ice is adding to the problem. The effects of rising global temperatures are often dramatic on land, causing heatwaves, wildfires, and vanishing glaciers, but their impact on the oceans is less obvious. So far the oceans have not warmed as much as the continents. This is partly because they warm up more slowly....

Power for the people

Small Scale Power Generation

Big power plants generating megawatts of electricity are essential for keeping large-scale infrastructure running, but households and small communities can provide some or even all of their own power without using fossil fuels. Some is in the form of electricity, and some in the form of heat energy. A lot of the technology used to produce this local power is still being perfected it is not as efficient as it might be, and it can cost a lot. But its efficiency will improve, and as more people...

Checks and Balances

Reasons For Checks And Balances

The energy that Earth soaks up from the Sun is more or less balanced by the energy that it radiates out into space, but only in the long term. Short-term imbalances can make the planet colder or warmer. These temperature changes can lead to mass extinctions, like the one that wiped out the dinosaurs 65 million years ago. Once the balance is upset, this can lead to other changes in Earth's climate system, which are called feedbacks. There are two types of feedback. Negative feedbacks resist...

The Greenhouse Effect

Earth Atmospheric Layers

Earth would be a lifeless ball of rock if it did not have an atmosphere. This is partly because living things rely on the atmosphere to supply them with essential elements such as carbon, nitrogen, and oxygen. Living things also depend on the atmosphere to maintain the temperature that they need to survive. The layers of air that surround the planet act as both sunscreen and insulation, shielding life from the fiercest of the Sun's rays while retaining heat that would otherwise escape back into...

Adapting to climate change

We have to combat climate change if we are to reduce the risk of catastrophic events in the future. Yet whatever we do, some change is inevitable. Even if we stopped all greenhouse gas emissions tomorrow, the average global temperature would still keep rising for the next 30 years, mainly because of the gradual release of heat stored by the oceans. The rising temperatures are bound to raise sea levels. They may also cause more droughts and floods, and create problems for agriculture and...

Predicting future climates

Predicting the future has never been easy. It is clear that adding more greenhouse gases to the atmosphere will make the planet warmer, but how much warmer will it get, and what effects will this have on the world There are a lot of factors to consider, and scientists try to take account of them all by building them into mathematical models of the climate, and using computers to see what happens when the figures for greenhouse gas emissions are increased. The resulting projections agree that if...

Heatwaves and droughts

By studying weather and climate data gathered from all over the world, and transmitted from orbiting satellites, scientists can compare it with past records to work out how much the world has warmed up. But for many people, the evidence of climate change is much more obvious. They are suffering heatwaves that can raise temperatures to lethal levels, and living with droughts that make drinking water scarce, kill their crops and farm animals, and turn fertile land to desert. Some of the droughts...

Greenhouse Gas Emissions By Weight

A number of gases released through human activity are increasing the power of the greenhouse effect. This diagram shows the relative quantities of the major human-produced greenhouse gases. The most important is carbon dioxide, because so much of it is released every year. The other greenhouse gases are emitted in smaller quantities, but they have a big effect because they are more powerful than carbon dioxide. extraction, processing, and distribution 8.4 Of all the greenhouse gases that we are...

Fossil Fuel Consumption

The main source of all the extra carbon dioxide in the atmosphere is the burning of fossil fuels. These include coal, oil in all its refined forms, and natural gas. All these fuels contain a lot of carbon. This chart shows that the annual consumption of fossil fuels varies by region and by country. The biggest consumers of fossil fuels are the United States, China, and the European Union. Coal produces far more carbon dioxide per unit of energy than the other fuels, so countries that burn a lot...

Burning the Forests

Pobble 365

Climate change is being caused by a combination of factors, but the most important is the increase of greenhouse gases in the atmosphere, and especially carbon dioxide. Most of this extra carbon dioxide is being released by burning carbon-rich fuels. This is the same process that turns sugar into energy in our bodies, but it is more violent, releasing the energy as searing heat. The most basic of all fuels is wood, which people have been burning for thousands of years to keep warm and to cook...

Climate Change

Satellite infrared image of Earth's temperature at night LONDON, NEW YORK, MELBOURNE, MUNICH, AND DELHI Project editor Margaret Hynes Managing editor Camilla Hallinan Managing art editor Owen Peyton Jones Art director Martin Wilson Publishing manager Sunita Gahir Category publisher Andrea Pinnington Picture researcher Sarah amp Roland Smithies DK picture library Lucy Claxton, Rose Horridge, Myriam Megharbi, Emma Shepherd, Romaine Werblow Production editor Hitesh Patel Senior production...

Tidal barrages

A hydroelectric dam can be built across a tidal inlet on the coast. Gates in the dam open to allow water in as the tide rises every day. At high tide the gates are closed, and as the tide falls again, the water behind the barrage is allowed out through turbines linked to electricity generators. Some systems like this tidal plant in France exploit both the incoming and outgoing tide. Tidal barrages produce clean electricity, but they can be extremely damaging to coastal wildlife habitats because...

Adding to the problem

Deforestation and the use of fossil fuels are not the only human activities causing climate change. Other aspects of modern life are adding to the problem. Some produce more carbon dioxide, as well as other greenhouse gases such as methane, nitrous oxide, and chlorofluorocarbons (CFCs). These other greenhouse gases are released in much smaller quantities than carbon dioxide, but they have a serious impact because they are much more powerful. A molecule of methane, for example, has the same...

Transportation

Nearly all forms of transportation rely on fossil fuels that release carbon dioxide. But some use fuel more efficiently than others. Trains can run on electricity, so they do not have to carry heavy fuel to power big engines. The least fuel-efficient form of transportation is air travel, especially over short distances, because of the power needed just to get airborne. Russia 11.5 tons p.a. Population 141.4 million 10.8 tons p.a. Population 127.4 million 10.7 tons p.a. Population 60.8 million...