Climate change - a much-used term with many meanings. There are numerous other terms, such as climate change and climate variability. But what exactly does it mean? It refers to the global change in the Earth's climate - through cooling or warming, the latter of which is currently happening. Both have occurred since the earth has existed and both pose major risks for humans and the environment, as the extent and consequences are very difficult to assess.

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 been happening even faster since this millennium than in previous decades.
And one thing is now also clear: we humans are responsible for a significant proportion of the rise in temperature. This was recently confirmed by the Intergovernmental Panel on Climate Change (IPCC) in its latest report on the current state of international climate research. This report scientifically underpins the links between extreme weather events and climate change.

Who and what is the Intergovernmental Panel on Climate Change?

The global climateat oalso known as the Intergovernmental Panel on Climate Change (IPCC), based in Geneva, is an institution of the United Nations, which regularly compiles the current state of knowledge on climate change and evaluates it from a scientific perspective. It maps out different options for action without proposing specific solutions and therefore lays the foundation for science-based climate protection.political decisions. Within the scientific community, the reports are regarded as the credible and well-founded presentation of the state of scientific, technical and socio-economic research on the climate and its changes.

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

Facts about climate change

Let's start with the basics: What exactly is happening as a result of global warming, what does the report say about it and what does it mean for us?

1. THE WORLD IS GETTING WARMER

The earth's temperature fluctuates from year to year, that is clear, but it has risen enormously in the last 50 years. 16 of the 17 warmest years since records began occurred after the year 2000, the five warmest since 2010. Since 1977 - i.e. for four decades now - there has not been a year on Earth that was cooler than the 20th century average.

In the current debate, there is often talk of global warming of up to "1.5 degrees Celsius" or "well below 2 degrees". What exactly does this mean? In the Paris Climate Agreement of 2015, 195 countries signed up to limiting average global warming to the aforementioned "1.5" or "well below 2 degrees". This refers to the warming since before industrialization until today, i.e. before we humans increased greenhouse gas emissions through production and progress. Currently, the global temperature has risen by around 1.1 degrees Celsius compared to the period between 1850 and 1900. The IPCC report sets out possible scenarios for the consequences of a rise in temperature. One very likely scenario shows that we will have reached the 1.5 degree Celsius increase by 2030 instead of by the middle of the century, as previously assumed. However, depending on how emissions are reduced in the coming years, the 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 now no longer any doubt about the human influence on global warming. It is now clear to almost everyone that carbon dioxide is warming the planet. The global concentration of CO2 in the air has risen by almost 50% since the beginning of industrialization, most of it since the 1960s.
Initially, 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 fluctuates naturally over a longer period of time and, according to climate researchers, volcanic eruptions can sometimes even cool a planet down. 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 cover 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 is further accelerated.
Sea levels could rise by 90 centimetres or more by 2100. However, the melting sea ice is not responsible for the rise in sea levels, as it is already in the water. The ice on land, i.e. mountain glaciers, is the problem. Their melting is responsible for a rise in the seas, which has already caused devastating flooding in coastal regions. Worldwide, 40 percent of humanity, around 2.8 billion people, live less than 100 km from a coast - by 2030, this could rise to 50 percent. For every centimeter of sea rise, up to one meter of coastal land is lost to the sea. The fact that it rained for the first time since weather records began at the highest point of the Greenland ice sheet, 3,216 meters above sea level, in August this year also shows that acute changes are underway here. Previously, only precipitation in the form of snow had been measured here.

4. ACIDIFY THE OCEANS 

To stay with the oceans: The oceans are gigantic carbon reservoirs and absorb considerable 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 ocean and the atmosphere is happening too slowly, or we humans are emitting too much CO2 too quickly. The ocean is no longer able to absorb CO2 fast enough. In addition, the CO2 storage capacity decreases with higher water temperatures and sinking pH-value . Another vicious circle: the absorption of CO2 in the water forms a weak acid, the sum of which causes pH-value to fall. This is known as ocean acidification. Since the beginning of industrialization, the acidity of the sea surface has risen by 30 percent. The change in pH value also has consequences for marine life, as phytoplankton, the first link in the marine food chain, reproduce very slowly in acidic water. The formation of calcium carbonate, which corals need, is also affected by the acidification of the oceans.

5. THE WEATHER BECOMES MORE DESTRUCTIVE 

Climate change is making storms and droughts more likely and more severe, especially in the case of heatwaves. The Intergovernmental Panel on Climate Change has even been able to establish that the number of extremes is increasing disproportionately faster 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.
One example from the report: heat events over land that were so severe that they only occurred once every 50 years in the 19th century are now around 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), at 2 degrees somewhat more frequently than every four years (13.9 times more likely). And with 4 degrees of warming it would be almost 40 times more likely, which means: extreme heat basically every year.

Global warming also removes moisture from the land and 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 heavier, for example the flooding in NRW, Rhineland-Palatinate and Bavaria in July. According to the IPCC report, droughts will increase particularly in the Mediterranean region and in western North America, but also in western and central Europe and in many parts of Africa. Only in northern Australia could droughts become less frequent. However, there is insufficient data available 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, which cannot be explained by natural influences. Rather, the report explains that such cyclones, which occur during heavy rainfall events and are highly 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 distribution areas solid that are now too warm for them. Species extinction is the final step. And to stay with the melting sea ice: The retreat of the ice is driving walruses by the thousands towards the Alaskan mainland. Global warming and the resulting acidification of the oceans is also leading to global coral bleaching and reef mortality.

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

Researchers at the Intergovernmental Panel on Climate Change show that even if we humans reduce our greenhouse gas emissions, we will only see the results much later, because many changes that are attributable to past and future greenhouse gas emissions cannot be reversed for centuries or even thousands of years, especially changes to the oceans, ice sheets and global sea levels.

The scenarios of the IPCC report

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

The most favorable and desired scenario for us:

If we were able to radically reduce man-made greenhouse gas emissions as early as this decade, i.e. by the end of 2030, the global temperature could rise by only around 1.5 degrees compared to the period between 1850 and 1900. As envisaged by the Paris Climate Agreement. According to the IPCC, only 500 billion tons of greenhouse gases would need to be blown into the air to achieve this - at current emission levels, this amount would already be reached in 13 years. Unfortunately, there is currently no indication that emissions can be reduced so quickly and significantly. Politicians need to take action 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. However, climate researchers have fortunately rejected these scenarios or classified them as unrealistic, as mankind would have to increase the burning of fossil fuels in an unrealistic manner in order to achieve these extreme scenarios.

The optimistic scenario:

In this scenario, global greenhouse gas emissions begin to fall steadily in this decade and 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 achieved after 34 years at today's levels.

The realistic scenario:

The development that seems most realistic anticipates a further increase in greenhouse gas emissions by the middle of the century and a gradual decrease 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.

Bundestag election is a climate election

The extent to which temperatures rise therefore depends on CO2 emissions. And one thing is clear: the sooner we act, the better. Admittedly, in view of the precarious facts and the climatic consequences that global warming has already caused, we often feel hopeless and helpless. And to be honest, these conditions often worry me too. But precisely because we now know the facts, we have to act! The optimistic scenario is not unattainable and unchecked global warming due to 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 conditions that are needed to achieve this or at least the realistic scenario.

On September 26, i.e. next Sunday, there will be a climate election and your cross will help decide whether and how quickly these urgently needed framework conditions for the national and international reduction of greenhouse gases are set.

We put our cross - for the climate. Are you with us? 

Your JUNGLÜCK team