This article was published in our September 2018 newsletter. Sign up here.
A quick glance at the satellite images to check whether I will need a rain jacket for the commute into work. And for my next weekend away I will find myself a place with plenty of sunshine, pleasant temperatures in the mid-twenties and a light breeze. These days, we can all access our personal weather forecasts online.
Forecasting the longer-term future
Just as weather forecasts are based on weather models, climate change predictions also rely on modelling, but with one key difference: climate models relate not only to the next few days but to the next 50 to 100 years at least. Among other things, they chart man-made climate change, that is to say the build-up of carbon dioxide in the atmosphere that is due in part to the burning of fossil fuels such as coal and oil, and the resulting warming of the lower atmosphere.
Data from the air and from the sea
By how much will carbon dioxide levels increase in the future? And how quickly will the average temperature on Earth rise? To compile reliable forecasts based on models, climate researchers depend on the data they feed into their models. These data are supplied by research ships, observatories, aircraft and satellite systems. The Alfred Wegener Institute (AWI) in Bremerhaven operates a number of research vessels, one being the Polarstern, which has been cruising the polar seas for more than 25 years. On 10 July 2018, the ship set off on a journey to the Arctic Ocean with 48 scientists on board. Its mission is to recover moorings fitted with probes from the sea between Greenland and Spitsbergen. They will provide information about water temperature and currents; it is also hoped that they will explain among other things why the warm West Spitsbergen Current from the Atlantic mixes with the colder currents from the Arctic.
Simulating climate change
The complex climate models developed at the Max Planck Institute for Meteorology in Hamburg – to name but one example – illustrate the global weather dynamics in our planet’s atmosphere. They can be used to take a very detailed look at specific periods of time or processes. By contrast, models of medium complexity are particularly well-suited to studying the climate system as a whole over periods lasting centuries or even millennia. These are the kind of models used by the natural and social science experts at the Potsdam Institute for Climate Impact Research (PIK). "For one thing, we can run up to 1,000 consecutive simulations with these models, which allows us to calculate how probable it is that certain future scenarios will occur. And for another thing, such models can be combined", explains PIK Scientific Coordinator Dr Ingo Bräuer. This means that reciprocal effects can be more easily studied, for instance between processes in the atmosphere and oceans, or between vegetation development, land use and agricultural policy decisions.
Testing out climate protection strategies
For the purposes of their simulations, PIK researchers take not only physical data but also social developments into account. They ask for example what impact it would have if other countries followed the example of the United Kingdom and the Netherlands and imposed charges on carbon emissions.
One current PIK study found that one controversial strategy aimed at limiting global warming has only little potential. The idea is to use large-scale plantations to capture CO2 from the atmosphere. Although the burden on the atmosphere would be relieved if excess CO2 were to be removed in this way, however, vital commodities such as clean water or land for growing food would be reduced at the same time.
Germany: a climate research hot spot
Since 2007, climate researchers in Germany have joined forces in the German Climate Consortium. Besides PIK (which was founded in 1992) and the AWI, more than 20 other research institutions and universities belong to the consortium, as do official agencies such as the German Environment Agency, Germany’s national meteorological service Deutscher Wetterdienst and the Max Planck Institute for Meteorology in Hamburg.
The team responsible for the next assessment report of the Intergovernmental Panel on Climate Change (IPPC) comprises 721 experts from 90 countries – more than a third of whom work in Germany. There is also a European platform for researching climate change and its consequences – AXIS. One of the jobs of the climate researchers in the AXIS network is to make sure that the data gathered around the world, the methods by which they are recorded and the various climate models are comparable. This is so that societies can better prepare themselves to cope with storms, heavy rainfall and drought – the kind of extreme weather events that climate change is already causing. And so that they can halt man-made climate change. After all, unlike the weather, we can do something about climate change.
Climate Service Center
While climate researchers study the climate and the consequences of climate change, policymakers, governments and companies have the job of developing adaptation strategies. To what extent do cities need to adapt their waste water management systems to heavy rainfall, and how should farmers change their growing methods? What impact will climate change have on global supply chains? Natural and social scientists, economists and architects at the Climate Service Center (GERICS) work together to devise climate and climate change services. These include prototypes that are developed for a specific purpose and then transferred to other regions, users or sectors.www.climate-service-center.de