When exactly did climate change make itself felt?

The consequences of climate change

Climate change is already clearly visible in the polar regions. Just a few decades ago, the Arctic Ocean was largely covered by ice. But this ice sheet is melting due to the rising temperatures: in the last 30 years its area has almost halved. At the same time, the ice layer is getting thinner and thinner. Climate researchers have calculated that the ice could melt completely in the next 20 years. The sea level would rise by a few meters as a result. But it's not just the ice sheets on the poles that are melting. The high mountain glaciers are also losing mass.

Because the sea level rises as the ice melts, ever larger coastal areas are flooded. Low-lying island states, such as the Maldives in the Indian Ocean or Tuvalu in the Pacific, are therefore increasingly threatened by storm surges. And not only the sea level, the water temperature also rises with climate change. As a result, more water evaporates and more water vapor is stored in the air. This increases the greenhouse effect, which further heats the atmosphere. This also increases the risk of severe weather such as heavy rain and hurricanes.

In arid regions, deserts are spreading due to rising temperatures. More and more droughts are causing rivers to dry up and areas of land that were previously green wither. In the south of Spain, for example, the usual rainfalls that are urgently needed for agriculture have been absent for years. And the water shortage in southern Europe continues to intensify.

All of these consequences of climate change can already be observed. Climate researchers are trying to calculate how things will continue with the help of computer models. But the future is difficult to predict because so many influences determine our climate. The salty sea water is diluted with fresh water by the melting of the glaciers. However, the salinity of the sea drives the ocean currents. So what could happen if the warm Gulf Stream breaks off due to the lower salt content? Will it be colder instead of warmer in Europe? What would happen if the permafrost thawed in the far north? Do tons of the greenhouse gas methane then escape from the ground? And will it accelerate climate change?

So far, no one has been able to give an exact answer. With all the unanswered questions, one thing seems certain: if we don't drastically reduce our carbon dioxide emissions, temperatures on this globe will continue to rise.

12.8.2013

The ice-bear melts the clod from under his paws. As a result of global warming, the sea ice around the North Pole is disappearing, and faster and faster. This is due to the greenhouse effect, which is caused by the emission of carbon dioxide and other gases that are harmful to the climate.

In 1980 the Arctic Ocean was still frozen over 7.8 million square kilometers, an area about the size of Australia. Within 30 years the ice surface has shrunk to about half! The ice sheets are already thawing in spring. If it continues like this, the "eternal ice" will soon be completely gone.

This is a disaster for the polar bear. Environmental organizations fear that polar bears and seals will become extinct in the next 20 years. Migratory birds are also losing their breeding grounds in the Arctic due to the changed climate.

Another marine predator, on the other hand, is already finding new habitat: Because the ice continues to recede, the orca can now also search for food high up in the north.

Short cut through the Arctic Ocean

The ice in the Arctic Ocean is melting dramatically. This has opened up a trade route between Europe and Asia: the Northeast Passage. This sea route runs along the north coast of the continents of Europe and Asia. In the past, large transport ships could only pass this route in midsummer. Because the Northeast Passage was frozen over most of the year and was much too dangerous because of the ice masses. Ships traveling between Rotterdam and Tokyo therefore took the long route through the Mediterranean, the Suez Canal and around India.

New satellite images show that the path through the Arctic Ocean is becoming more and more ice-free. This makes the journey easier for ships - even without an icebreaker. This saves time and transport costs, because the route through the Arctic Ocean is several thousand kilometers shorter than the old route through the Suez Canal.

15.6.2014

It is the mightiest of all Alpine glaciers: the Aletsch Glacier in the Bernese Alps is over 23 kilometers in length. Its ice cover is up to 900 meters thick. Still! Because the white splendor of the glaciers could soon be history.

For decades, researchers have observed that the ice masses are decreasing. They lose an average of half a meter in thickness every year. Climate change is to blame, which is causing temperatures on earth to rise: In the ever warmer summers, more ice melts than is added in the cold season. The ice giant was particularly troubled by the hot summer of 2003: at that time, large parts of the glaciers had melted away. It is now even feared that the alpine glaciers could have disappeared in 30 years.

That would be a great loss for the landscape of the Alps - and a catastrophe for tourism: many winter sports locations make their living from ski areas on glaciers. When the ice and snow melt, tourists stay away too. In addition, there will be water supply problems when the glaciers die. Because huge amounts of fresh water are stored in their ice masses. Many places would then have to transport their drinking water expensively and from far away.

Cling film for glaciers

To protect their glaciers from rising temperatures, the Austrians have come up with something: they cover their glaciers with plastic cling film in summer. The almost four millimeter thick, white film is supposed to reflect the sun's rays and thus prevent ice and snow from melting. And indeed: Glacier researchers confirm that the film greatly reduces melting.

Glacier foils are now also being used in Switzerland and Germany. The Zugspitze now also gets a “sun hat” on a regular basis. Climate activists criticize that while this slows down the melting of the ice for some time, global warming cannot be stopped in this way.

30.11.2011

The frozen soils of the Arctic are thawing faster than previously thought due to climate change. This could release huge amounts of the greenhouse gas methane into the atmosphere. That would additionally accelerate the warming of the earth.

Permafrost soils extend over huge areas in the northern hemisphere. They are mainly found in large parts of Siberia and Alaska. Their name comes from the fact that they are frozen all year round - at least so far. But temperatures on earth are rising. For some years now, the frozen soils in the far north have been warming, starting to thaw and turning into huge swamps.

Scientists suspect that the thawing permafrost could accelerate climate change. Because the soils contain methane, a gas produced by microorganisms. This greenhouse gas has about 20 to 30 times more impact on the climate than carbon dioxide. In addition, large amounts of carbon are stored in the frozen ground. A devilish cycle begins here with rising temperatures: If the permafrost thaws due to climate change, methane and carbon dioxide are released into the air. The greenhouse gases warm the atmosphere, the earth heats up, the ice melts - and climate change is exacerbating itself.

So far, researchers have disagreed about how quickly the permafrost will thaw. The question of how many greenhouse gases are actually released has not yet been clarified.

Koala bear in climate change

Gloomy prospects for the koala bear: The cute marsupial is massively threatened by climate change. Because the greenhouse gas carbon dioxide makes the leaves of his favorite food inedible: eucalyptus leaves become inedible by the rising CO2-Content in the air leathery and inedible. Because their nutrient content is reduced, the koala has to eat significantly more eucalyptus in order to be satisfied. This also applies to other marsupials and marsupials similar to them. Many other animal species are also directly at risk from climate change, especially in the polar regions. Ringed seals and emperor penguins are losing their habitat due to the receding ice. And the arctic beluga whale is finding less and less prey. What to do? The World Conservation Union (IUCN) emphasizes that the individual is not powerless. Everyone can reduce their carbon dioxide emissions and stand up for climate protection.

17.10.2009

The rise in sea levels could soon doom the Maldives. If climate change is not stopped, much of the islands will be submerged by 2100. President Mohamed Nasheed wants to raise awareness of this threat. So he went to a diving station with his cabinet.

It was a spectacular action: Maldives President Mohamed Nasheed jumped into the turquoise blue sea in a diving suit, followed by his eleven ministers. The cabinet held a climate conference on the ocean floor. The message to the rest of the world: Save the Maldives from ruin!

The Maldives are best known as a vacation paradise. But the islands in the Indian Ocean are threatened by climate change: their highest point is only two and a half meters above sea level. And if the water continues to rise due to global warming, that will soon mean “land under” for the dream islands. According to climate researchers, an increase of 20 to 60 centimeters would be enough to make the Maldives largely uninhabitable. In addition, storms and storm surges are becoming more frequent due to climate change - the situation for the island nation is getting worse.

The coral reefs around the islands form a protective barrier against storm surges. But these too are suffering from climate change and some of them are already badly damaged.

Corals in danger

A colorful underwater world is what makes the Maldives so special. Coral reefs, which are home to many marine animals and plants, surround the islands. The reefs are a natural protective barrier from the tides. With a gently rising sea level, the reefs could even grow with it - provided they are healthy. But this is where the problem begins: the reefs themselves are threatened by climate change and are already severely damaged. This is due to the so-called coral bleaching, also known as "coral bleaching". The coral sticks initially bleach and eventually die. This disease is caused by the warming of the sea. Because coral bleaching occurs not only around the Maldives, but already in many places, it is considered a global threat to reefs.

15.8.2011

East Africa is experiencing the worst drought in 60 years. Hardly a drop of rain fell for seven months - with catastrophic consequences: the harvest has dried up, water is scarce, and millions of people are hungry and thirsty. Hundreds of thousands of Somalis are fleeing across the border into Kenya and Ethiopia. But the refugee camps there have long been overcrowded.

Due to the lack of water, neither fields can be irrigated nor cattle supplied. Poor harvests mean that food prices continue to skyrocket. Political conflicts in Somalia, a country with a civil war, make the situation even worse. And the drought continues.

The United Nations has already declared famine in five areas of Somalia. More than twelve million people are dependent on outside help, hundreds of thousands are on the run. In July, 40,000 starving people arrived in Dadaab, the largest refugee camp in northern Kenya, and more than a thousand are added every day. But even when they reach the camps - for many refugees from hunger, any help comes too late: More and more people are dying of malnutrition.

Because the onslaught of refugees continues, more emergency shelters have to be set up quickly. Drinking water and hygienic supplies in the camps are becoming scarce, and living conditions are deteriorating every day. Aid organizations call for donations worldwide.

When the rain stops

Somalia once had two reliable rainy seasons, they were called Gu and Deyr. If they failed, it was a rare disaster. Grandchildren and great-grandchildren were also told about it. But for a few decades now, droughts have been increasing in Somalia and East Africa. In the last five years there has only been one with the usual rainy seasons. It is probably not a coincidence. Climate experts have long predicted that climate change will spread the earth's arid zones. Africa will therefore be plagued by droughts even more in the future. In East Africa this suspicion is being confirmed in a shocking way.

4.11.2011

Global carbon dioxide emissions have never been as high as they are today. In 2010, it even rose more sharply than ever before. This has now been announced by the US Department of Energy. The numbers exceed even worst fears.

For years, experts have warned of the speed of global warming. Apparently without success: The proportion of the climate-damaging gas carbon dioxide in the air is increasing rapidly. In the industrialized countries in particular, it gushes continuously from chimneys and exhaust pipes. The new numbers are frightening: In total, the world emitted over 33,500 million tons of carbon dioxide in 2010. That is 1,900 million tons more than in the previous year, an increase of six percent!

According to the US study, China and India are primarily responsible for the increase in horror. The two countries are on a growth path economically. They get their energy primarily from coal-fired power plants - and thus produce a lot of CO2. Overall, China is the record holder for greenhouse gas emissions, followed by the USA, Russia and India.

The policy for global climate protection has so far failed completely. China and the US refuse to sell their CO2- to reduce emissions. Russia, Canada and Japan also no longer want to comply with guidelines if the main polluters are reluctant to comply with international limit values. Bad for the climate, as the new study clearly confirms on the basis of the figures.

The Keeling curve

The first CO2-Measuring station in the world was opened far away from car exhaust fumes and factories: In 1958, the American climate researcher David Keeling began to regularly measure the carbon dioxide content of the air on the Mauna Loa volcano on the island of Hawaii. This place was chosen deliberately. Because neither chimneys nor forests influenced the result, an average value of the trace gas in the air could be measured here. A second station in Antarctica also met these conditions. After two years, Keeling presented his results to the world: The level of carbon dioxide in the air rose! In the following years, Keeling continued to fight for regular CO2-Measurements of the atmosphere. With success: The result is the so-called Keeling curve, a collection of data that continues to record the carbon dioxide content of the air and the significant increase in CO2 documented.

The global warming

It is getting warmer and warmer on earth. In the last hundred years alone, the average temperature has risen by almost one degree Celsius. The main reason for this warming is the increased proportion of carbon dioxide in the air. This CO2-The main cause of the increase is the industrialized countries through the burning of oil, gas and coal.

Plants, on the other hand, have a protective effect on the climate. They can absorb carbon dioxide from the air and convert it into organic compounds during photosynthesis. The tropical forests store a particularly large amount of carbon dioxide. Because large areas of forest are being cleared in the tropics, this storage function is becoming smaller and smaller. Because where there is no tree, no more carbon dioxide is taken from the air. The greenhouse effect increases and the atmosphere warms up.

So will we soon be swimming in the lake in winter instead of sledding? Difficult to predict. Scientists are trying to calculate by how many degrees Celsius the earth will heat up in the future with the help of computer models. According to these models, the average temperature on earth could rise by a further one to six degrees by the year 2100. How the temperature curve will actually run depends above all on whether the proportion of carbon dioxide continues to rise.

The serious consequences of climate change can already be seen: The ice masses are melting, the sea level is rising, storms and droughts are increasing. It is all the more important to reduce greenhouse gas emissions, especially CO2. Because this trace gas remains in the atmosphere for a long time. Only if we blow less of it into the atmosphere can man-made climate change at least be slowed down.

Some industrialized countries have therefore committed to reducing their greenhouse gas emissions and certain CO2-Values ​​not to be exceeded. But despite a series of climate summits, the global community has not yet succeeded in curbing the rise in carbon dioxide in the air.

The greenhouse effect

In a greenhouse, vegetables or flowers can thrive even when it's cold outside. That's because greenhouses are built out of glass.The glass - or a transparent film - allows the short-wave rays of the sun to enter the interior unhindered: the air warms up. On the other hand, the glass is impermeable to long-wave heat radiation, so the heat can no longer get out. That’s why it’s cozy and warm in a greenhouse.

Something similar is happening on a large scale on earth. The greenhouse gases carbon dioxide (CO2) and water vapor are naturally present in the atmosphere. Water vapor enters the air through evaporation, carbon dioxide through the exhalation. Volcanic eruptions also contribute to the natural carbon dioxide content of the air. Both gases have the same effect as the glass in a greenhouse: They allow the short-wave rays of the sun to penetrate to the earth. At the same time, like an invisible barrier, they hinder the long-wave thermal radiation on its way back into space. The heat builds up and the atmosphere heats up.

Without this natural greenhouse effect, life on earth would hardly be possible, because it would be far too cold for most living things. Instead of the current average temperature of plus 15 degrees, it would be an icy minus 18 degrees Celsius. The surface of the earth would be frozen!

The problem starts when we increase the amount of greenhouse gases in the atmosphere. This is mainly done by burning oil, natural gas and coal. Heating the apartment, driving a car, burning garbage: all of these processes emit carbon dioxide. This CO2 has the largest share in the man-made greenhouse effect. But the cultivation of rice or cattle farming also increase the effect: Large amounts of methane (CH4) - also a greenhouse gas. In addition, nitrous oxide, ozone and fluorocarbons are among the greenhouse gases. Because all these gases slow down the earth's heat radiation, the temperatures on our globe continue to rise.

Who will be hardest hit by climate change?

We already have less snow in winter than there was a few decades ago. In return, the plant growth begins earlier in the year and we can now bathe well into autumn. But the lack of white splendor and the longer bathing season are among the more harmless consequences of the rise in temperature.

No country on earth will be spared from climate change. When the sea level rises, large areas of land on all coasts of the world will be flooded. For rich countries like Germany or the Netherlands this is expensive, but not an insoluble problem. Here dams are built against the floods, which can withstand a strong rise in water.

The situation is different in poor countries: large parts of Bangladesh, for example, are only a few meters above sea level - and the poor country cannot afford expensive coastal protection. If the sea level rises by one meter, many millions of people lose their homes and have to relocate. The Maldives and the South Sea islands of Tuvalu can be even worse: These islands protrude only a few meters above sea level and could be completely flooded - then an entire country would have to move.

Regions that depend on the glaciers' freshwater reservoirs are particularly affected by climate change: If these glaciers thaw, there is a risk of flooding at first, and then, in the long term, of severe drought. Areas in the Himalayas and the Andes are particularly at risk. Over 200 million people could be left there in the future, will hardly have any drinking water and will not be able to irrigate their fields.

Increasing water shortages also threaten the arid regions, which are spreading further on earth. In 2011, for example, East Africa experienced a drought from which hundreds of thousands of people had to flee. Thousands were killed in the disaster. Many countries lack the money to protect themselves from climate change and its consequences. And it is often precisely the countries that produce only a few greenhouse gases that are particularly hard hit by the effects of climate change.

Warm times - cold times

There were times on earth when large areas of land were buried under a thick sheet of ice. The ice masses even penetrated close to the equator at times. In alternation with the ice ages, this planet was hit by gigantic heat waves. For millions of years it was so hot that palm trees could even grow at the North Pole. Ice and warm periods have alternated since the earth has existed. Climate change occurred long before humans inhabited the earth. And these natural climate changes left their mark.

During the ice ages, the glaciers expanded. Ice masses grinded the subsoil, planed valleys and pushed masses of debris in front of them. As long as it was cold, large amounts of water remained bound in the ice, which caused the sea level to drop. As soon as the temperatures rose again, the ice melted and the sea level rose again. Valleys and depressions filled with water, became rivers and lakes.

Animals and plants appeared or disappeared with the temperature changes. For example, many different types of dinosaurs lived in a particularly warm phase. When it got cooler, many of them died out. Animals such as mammoth, reindeer and bison were typical of the last ice age. With the rising temperatures, they disappeared from the scene or they moved to cooler regions. Reindeer, for example, still have their home in Northern Europe, Siberia and Canada.