The earth is burning – what is the state of our climate?

Climate change - a widely used, meaningful term. There are many other terms, such as climate change and climate change. But what exactly does that mean? It is about the global change in the Earth's climate - through cooling or warming, the latter is currently happening. Both have existed since the Earth was created and both pose great risks for people and the environment, as the extent and consequences are very difficult to estimate.

What is probably well known is that it is getting hotter and drier, the sea ice in the Arctic and glaciers around the world are melting, the oceans are warming, becoming more acidic and sea levels are rising. And all of this has happened even faster since this millennium than in the decades before.
And one thing is now clear: we humans are responsible for a significant part of the increase in temperature. The IPCC recently confirmed this in its latest report on the current status of international climate research. This report scientifically underpins the links between extreme weather events and climate change.

Who and what is the IPCC?

The Intergovernmental Panel on Climate Change (IPCC) , based in Geneva, is a United Nations institution that regularly compiles the current state of knowledge on climate change and evaluates it from a scientific perspective. It presents different options for action without proposing concrete solutions and therefore lays the foundation for science-based political decisions. The reports are considered within the scientific community to be the most credible and well-founded representation of the current state of scientific, technical and socio-economic research on the climate and its changes.

In mid-August 2021, the first part of a six-part report on the current climate situation was published, on which my statements in this article are also based.

Facts about climate change

1. THE WORLD IS GETTING WARMER

The Earth's temperature varies from year to year, that's clear, but it has risen enormously in the last 50 years. 16 of the 17 warmest years on record occurred after 2000, and the five warmest since 2010. Since 1977 - four decades now - there hasn't been a year on Earth that was cooler than the 20th century average.

In the current discussion, there is often talk of global warming of “1.5 degrees Celsius” or “well below 2 degrees”. What exactly does that mean? In the Paris Climate Agreement of 2015, 195 countries signed to limit average global warming to the aforementioned “1.5” or “well below 2 degrees”. This refers to the warming from the time before industrialization to today, i.e. before we humans increased greenhouse gas emissions through production and progress. The global temperature has currently risen by around 1.1 degrees Celsius compared to the period between 1850 and 1900. The IPCC report presents possible scenarios for the consequences of a rise in temperature. A very likely scenario shows that we will have reached the increase of 1.5 degrees Celsius by 2030 instead of only by the middle of the century, as previously assumed. Depending on how emissions are reduced in the coming years, researchers assume that we will have exceeded 1.5 degrees by 2040 at the latest. The question is therefore no longer whether we can stop global warming by 1.5 degrees, but how long we can delay it and at what temperature we can keep it.

2. CLIMATE CHANGE IS MAN-MADE

According to the IPCC report, there is no longer any doubt about the human influence on global warming. It is now clear to almost everyone: carbon dioxide is warming the planet. The global CO2 concentration in the air has increased by almost 50% since the beginning of industrialization, most of it since the 1960s.
First, of course, attempts are made to find a natural cause for the rise in temperature, but none can explain the warming trend of the last 50 years. Solar radiation naturally fluctuates over a longer period of time and, according to climate researchers, volcanic eruptions can sometimes even cool a planet. Only CO2 and other greenhouse gases show a steady increase and ensure that less heat can escape from the planet. More than nine out of ten climate scientists are certain that our CO2 emissions are the main cause of global warming.

3. THE ICE IS MELTING RAPIDLY

Arctic sea ice, like glaciers worldwide, is melting. Since records began in 1850, the average area of ​​sea ice in the Arctic has never been as low as it was between 2011 and 2020. The Arctic has warmed faster than the rest of the planet, and its ice sheet has become smaller and thinner as a result. It's a vicious circle: As sunlight is absorbed by the dark sea instead of being reflected by the ice, global warming continues to accelerate.
By the year 2100, sea levels could rise by 90 centimeters or more. However, melting sea ice is not responsible for sea level rise, because it is already in the water. The ice on land, i.e. mountain glaciers, is the problem. Their melting is responsible for rising sea levels, which has already caused devastating floods in coastal regions. Worldwide, 40 percent of humanity, about 2.8 billion people, live less than 100 km from a coast - by 2030, this figure could be 50 percent. For every centimeter of sea level rise, up to one meter of coastal land is lost to the sea. The fact that acute changes are underway here is also shown by the fact that at the highest point of the Greenland ice sheet, 3,216 meters above sea level, it rained for the first time since weather records began in August this year. So far, only precipitation in the form of snow has been measured here.

4. THE SEAS ARE BECOMING ACIDIFIED

To stay with the seas: The oceans are gigantic carbon reservoirs and absorb significant amounts of CO2 from the atmosphere. They currently contain around 60 times as much carbon (38,000 gigatons) as the pre-industrial atmosphere. However, this constant exchange between the sea and the atmosphere is happening too slowly, or we humans are emitting too much CO2 too quickly. The sea is no longer able to absorb CO2 quickly enough. In addition, the CO2 storage capacity decreases with higher water temperatures and falling pH values. Another vicious circle: the absorption of CO2 in the water forms a weak acid, which in total causes the pH value to fall. This is referred to as ocean acidification. Since the beginning of industrialization, the acidity of the sea surface has increased by 30 percent. The change in pH value also has consequences for marine life, because phytoplankton, the first link in the marine food chain, only reproduces very slowly in acidic water. The calcification that corals need is also affected by ocean acidification.

5. THE WEATHER BECOMES MORE DESTRUCTIVE

Climate change is making storms and droughts more likely and more severe, especially in the case of heat waves. The Intergovernmental Panel on Climate Change has even found that the number of extremes is increasing far more than the earth is warming. Parts of the earth could therefore become uninhabitable by the end of the century - especially around the equator - and cause many people to lose their homes and have to flee.
An example from the report: heat events over land that are so severe that they only occurred once every 50 years in the 19th century are now about five times as frequent, i.e. on average every ten years. If the planet warms by 1.5 degrees by 2100, such an event would occur approximately every six years (8.6 times more likely), and if it warms by 2 degrees, it would occur slightly more often than every four years (13.9 times more likely). And if it warms by 4 degrees, it would be almost 40 times more likely, meaning extreme heat basically every year.

Global warming also removes moisture from the land and the sea, which collects in the air and makes droughts more likely and more extreme. Precipitation in the form of rain or snow can also be more severe, for example in July with the floods in North Rhine-Westphalia, Rhineland-Palatinate and Bavaria. According to the IPCC report, droughts will increase particularly in the Mediterranean region and western North America, but also in western and central Europe and many parts of Africa. Only in northern Australia could droughts become less frequent. However, there is insufficient data on this for many regions.

The report also looks at tropical cyclones, which according to the researchers have been observed more frequently in categories three to five over the past forty years and have changed their movement patterns that cannot be explained by natural influences. Rather, the report explains that such cyclones, which occur during heavy rain events and are most likely to increase in intensity in this combination, can be attributed with a high degree of certainty to human influence.

6. ANIMALS AND PLANTS ARE AFFECTED

The climate is warming so quickly that evolution cannot keep up. We are already seeing the disappearance of animal and plant species in areas that are now too warm for them. The extinction of species is the final step. And to stay with the melting sea ice: the retreat of the ice is driving thousands of walruses towards the mainland of Alaska. Ocean warming and the resulting acidification of the oceans are also leading to coral bleaching and reef deaths worldwide.

Of course, there will also be adaptations: humpback whales are taking advantage of the new ice-free waters of the Antarctic and sea urchins are also more resilient than previously thought - to name just two examples. Nevertheless, the question remains: how many species can adapt to the new circumstances and up to what maximum temperatures?

Researchers from the Intergovernmental Panel on Climate Change have shown that even if we humans reduce our greenhouse gas emissions, we will not see results until much later, because many changes that are due to past and future greenhouse gas emissions cannot be reversed for centuries and thousands of years, especially changes in the oceans, ice sheets and global sea levels.

The scenarios of the IPCC report

What exactly are the possible temperature developments? The report calculates different scenarios, which I would like to briefly present to you.

The most favorable and desired scenario for us:

If we were able to radically reduce man-made greenhouse gas emissions this decade, i.e. by the end of 2030, we could manage to keep global temperatures from rising by around 1.5 degrees compared to the period between 1850 and 1900, as the Paris Climate Agreement envisages. According to the IPCC, in order to achieve this, only 500 billion tons of greenhouse gases should be released into the air - at current levels of emissions, this amount would be reached in just 13 years. Unfortunately, there is currently no indication that emissions could be reduced so quickly and significantly. Politicians would have to act here and present and implement a suitable, binding action plan.

The two pessimistic scenarios:

The IPCC also shows extreme scenarios with CO2 levels in the air in which greenhouse gas emissions would triple or double over a period of decades and continue to rise until the end of the century. In this case, global warming would increase to four to five degrees. Fortunately, climate researchers have rejected these scenarios or classified them as unrealistic, since humanity would have to expand the burning of fossil fuels in an unrealistic way to achieve these extreme scenarios.

The optimistic scenario:

In this scenario, global greenhouse gas emissions will begin to decline steadily in this decade and will reach zero in the 2070s. According to the IPCC, this would allow the two-degree target of the Paris Climate Agreement to be met. Humanity would only be allowed to release a good 1,300 gigatons of greenhouse gases into the air, which would be reached after 34 years at today's levels.

The realistic scenario:

The development that seems most realistic assumes a further increase in greenhouse gas emissions until the middle of the century and a gradual decline around 2070. This would result in a warming of almost three degrees compared to the end of the 19th century, i.e. almost two degrees more than today.

Federal election is climate election

How much temperatures increase depends on CO2 emissions. And one thing is clear: the sooner we act, the better. Admittedly, given the precarious facts and the climatic consequences that global warming has already caused, we often feel hopeless and helpless. And honestly, these situations often worry me too. But precisely because we now know the facts, we must act! The optimistic scenario is not unattainable and unchecked global warming caused by unregulated greenhouse gas emissions poses an enormous threat to health, prosperity and peace worldwide. We must force politicians to take climate change seriously and set the framework that is needed to achieve this or at least the realistic scenario.

Your JUNGLÜCK team