The recent floods across Europe took the world by shock, as two months’ worth of rainfall came pouring down on the countries in a span of a few days. Germany, Belgium, Netherlands, and Luxembourg were majorly affected, resulting in the loss of life, property, and infrastructure. It led to massive power outages and forced evacuations. The Ahr-Erft region in Germany and the area around the Meuse River in Belgium witnessed record breaking heights of 93mm and 106mm of rainfall within a day. These were seen as the worst affected countries with the death toll nearing 220 people. It was believed that the floods were caused by a low-pressure area over Central Europe, what German scientists dubbed Bernd, which is surrounded by high pressure systems. This low-pressure zone tapped tropical moisture from the Mediterranean and unloaded bursts of rain over a few days.
In a statement to BBC news, Annemarie Mueller, a 65-year-old resident of Mayen, Germany said “Nobody was expecting this – where did all this rain come from? It’s crazy. It made such a loud noise and given how fast it came down we thought it would break the door down.” In the aftermath of the disaster, Annemarie Mueller was not the only one left in confusion over this sudden event. In an attempt to unearth further reasons behind this sudden event, 39 scientists from Germany, Belgium, Netherlands, Switzerland, France, US, and UK, put together a study in the World Weather Attribution to understand the possible role that climate change and rising temperatures played in causing this sudden burst of rainfall and flooding.
They found that the severe flooding was caused by wet conditions that existed before the event, leading to already sodden grounds that are unable to absorb water, as well as local hydrological factors such as land cover and infrastructure. However, they could not focus purely on the floods since some of the hydrological monitoring systems—which would have given them more accurate information about the floods—were destroyed by the floods. This resulted in a lack of data on river flow over time. Thus, to understand the impact of climate change, they focused on the heavy rainfall that preceded the floods. They looked back at rainfall records and created a model to analyse how much rainfall the area might have received, both with and without the influence of climate change. They wanted to focus on the two worst impacted regions, i.e., Germany’s Ahr- Erft region and Belgium’s Meuse region. However, pinpointing the influence of climate change in these regions was harder because there are large amounts of variability every year in their local rainfall patterns. Therefore, they expanded the scope of their study to broader regions of Europe, to include Eastern France, western Germany, eastern Belgium, Netherlands, Luxemburg and northern Switzerland. They found that the amount of rainfall that falls within a day increased by 3 to19% as a result of climate change. Further, rising temperatures also increased the likelihood of such events from 2 to 9 times more likely, as warmer atmospheres can hold more water at a time, leading to bursts of torrential rainfall and severe flooding. Thus, global warming and climate change has been seen as the major cause for the European floods.
In order to assess the science related to climate change, as well as measure the impacts caused by it, a UN body called The Intergovernmental Panel on Climate Change (IPCC) was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) in 1988. It provided leaders from all around the world, periodic scientific assessments regarding climate change, as well as provided adaptation and mitigation strategies. They recently published their first report from the Sixth Assessment Report cycle, which will be completed by 2022. The report is titled “Climate Change 2021: the Physical Science Basis.” The report stated that the world is already 1.2 degrees celsius warmer than the pre-industrial levels. This is facilitated by human activities that cause climate change and global warming.
The global warming level of warning is 1.5 degrees celsius, and the sixth IPCC emphasised that unless immediate and rapid, large-scale reductions in greenhouse gas emissions take place, the world will move closer and closer to 1.5 degree celsius and even exceed it. A 1.5 degree celsius of global warming is characterized by increasing heat waves, longer warm seasons and shorter cold seasons. A 2-degree celsius global warming is characterized by heat extremes that would reach critical tolerance thresholds for agriculture and health.
The floods experienced in Europe, is just one of the many extreme events that is likely to follow with climate change and global warming. Coastal areas will continue to see a rise in sea levels, contributing to frequent flooding and soil erosion, affecting agriculture and infrastructure. Global ocean levels have risen about 20cm since the pre-industrial times, and the rate of increase has nearly tripled in the last decade. Sea levels are further affected due to reduction in the area covered by sea ice, which in the Arctic has shrunk by about 40% since 1979. If global warming is capped at 2 degrees celsius, then the ocean level will go up about half a metre over the 21st century mark. This will affect the homes of several wildlife species and possibly lead to extinction. Climate change has also resulted in an increase in the amount of carbon dioxide present in the atmosphere, which has risen by 25% since 1958, and by about 40% since the Industrial Revolution. The two most important absorbers of carbon dioxide, trees and oceans, are also affected by human activities and climate change. Increased water temperatures and higher carbon dioxide concentrations than normal results in higher acidic levels of oceans, thus affecting the lives of wildlife species and humans that depend on it for survival. The Amazon rainforests have already experienced loss of life and plantations due to forest fires caused by deforestation activities and heating up and drying out of the rainforests caused by rising temperatures. In the first seven months of 2020, more than 13,000sq km (5,019sq miles) of the Brazilian Amazon was burned.
UN Secretary-General, Antonio Guterres in a statement mentioned that to avoid such a situation and to limit the rising global temperatures, we must reduce global greenhouse gas emissions by 45% from 2010 levels by 2030 and reach net-zero emissions by 2050. We must phase out the use of coal by 2040. The Sixth Assessment report published by IPCC, also mentioned the importance of not only limiting carbon dioxide emissions, but also methane emissions. Methane emissions result from leaks in natural gas production, coal mining, landfills and livestock and manure handling. Forests, soil and oceans are our saviours in ensuring reduction of greenhouse gases, and a prevention in global warming. They are said to absorb about 56% of all the carbon dioxide emissions released by humans. We need to work towards conserving forests, preventing soil erosion and saving oceans and wildlife.
The recent flooding, followed by the reports published, is hopefully a wake-up call about the gravity of the situation we face in front of us. As Boris Johnson, Prime Minister of the United Kingdom mentioned, “We know what must be done to limit global warming—consign coal to history and shift to clean energy sources, protect nature and provide climate finance for countries on the frontline.” We just need to start taking the right action, and commit to aggressively fighting climate change.
Shreya Ramchandran is a second-year undergraduate Economics and Finance student at Ashoka University, and a prospective minor in psychology.