Karlsruhe Institute of Technology: Better predictions for air quality, weather and climate

By researching short-lived components of the atmosphere from the ground to the stratosphere, the German infrastructure ACTRIS-D – in which the Karlsruhe Institute of Technology (KIT) is also involved – is intended to help researchers overcome the uncertainties in predicting the future climate to reduce. They want to gain new knowledge about the interactions between different climate processes and evaluate measures to improve air quality and their effects on health and ecosystems. For its contribution to ACTRIS-D, KIT will receive around 14 million euros to set up new measuring facilities for cloud research, existing infrastructures such as the AIDA cloud chamber and the Garmisch-Partenkirchen / Zugspitze atmosphere observatory,

Fine dust particles, clouds and most trace gases are short-lived components of the atmosphere. In contrast to the long-lived greenhouse gases such as methane and carbon dioxide, which remain in the atmosphere for decades to millennia, they are usually only on the move for a few hours or weeks. Nevertheless, they have a major impact on air quality and the climate. Tiny suspended particles, for example, reflect sunlight and thermal radiation or serve as nuclei for the formation of cloud droplets and ice crystals, which in turn can lead to precipitation. However, it is not yet sufficiently known how large the, in some cases, very different effects are in each case.

“Climate change is a big, challenging task that we can only face together – across the borders of institutions and countries. ACTRIS-D will use the latest measurement technology to collect new types of data, analyze them in a global community and thus create knowledge for society, ”says the President of KIT, Professor Holger Hanselka. “KIT is excellently positioned in atmospheric research and will make a significant contribution here with know-how and efficient infrastructures.”

Precise measurement data for the distribution of aerosols

“At KIT, we want to collect precise and quality-checked data sets for trace gases, aerosols and clouds over long periods of time. This means that important processes in the climate system can be better researched and, above all, future changes can be better identified and analyzed, ”says Dr. Ottmar Möhler from the Institute for Meteorology and Climate Research – Department Atmospheric Aerosol Research (IMK-AAF) at KIT. “With the infrared and laser radar systems, that is, ground-based remote sensing, in Garmisch-Partenkirchen and on the Zugspitze, the AIDA cloud simulation chamber on the north campus of KIT and the mobile platform KIT-Cube, the KIT brings already established infrastructures.” ACTRIS-D can be expanded considerably for long-term operation.

More efficiency for atmospheric research

The atmospheric observatories at the Garmisch-Partenkirchen site, on the Zugspitze and at the Schneefernerhaus environmental research station measure the atmospheric content of trace gases such as ozone, ethane, formaldehyde or nitrogen dioxide as well as the vertical distribution of aerosols with the highest temporal resolution and accuracy. For this purpose, high-resolution infrared spectrometers and the latest laser radar systems are installed for long-term operation. Among other things, it is to be investigated how air pollutants get from the ground into the boundary layer and higher atmospheric layers and can subsequently be transported to other geographical areas. Last but not least, these atmospheric measurement data are used for quality control of satellite-borne earth observations.

In the AIDA aerosol and cloud chamber, the KIT researchers are investigating how clouds form and what influence they have on the weather and climate . “We now want to build a new, more powerful cloud simulation chamber as part of ACTRIS,” says Möhler. “Above all, we want to achieve even lower temperatures and air pressures in order to research trace gas, aerosol and cloud processes in the entire earth’s atmosphere under well-controlled experimental conditions.”

The fully mobile Karlsruhe Low-Cloud Exploratory Platform KLOCX will offer scientists new insights into the formation and dissolution of deep clouds. On the one hand, these clouds reflect sunlight back into space and, on the other hand, they hold back the heat radiation from the earth. How strong these effects are and under what conditions is one of the big questions in current climate research. Ground-based remote sensing measurements in KLOCX and satellite observations should shed light on these processes in the development of low clouds and fog

The KIT is also responsible for setting up and managing the calibration center CIS – Center for Cloud In-Situ Measurements. The CIS consortium is one of six European centers that specialize in remote sensing and on-site studies of aerosols, clouds and trace gases.

ACTRIS researches short-lived components of the atmosphere

In the European research infrastructure ACTRIS (stands for The Aerosol, Clouds and Trace Gases Research Infrastructure), numerous research institutions will investigate short-lived atmospheric components from 2022 and expand the observation and research of the Earth system. The Federal Ministry of Education and Research is funding the German contribution ACTRIS-D within the framework of the “Research for Sustainability” (FONA) strategy over the next eight years with a total of 86 million euros. This is coordinated by the Leibniz Institute for Tropospheric Research (TROPOS) in Leipzig. The funds will be used to expand or build numerous fixed and mobile measuring stations as well as laboratories and simulation chambers.

Across Europe, well over 100 research institutions from 22 countries participate in ACTRIS. They have spanned a network of more than 70 observatories across Europe, complementing stations in the polar regions, the tropics and Asia. ACTRIS is intended to offer a broad user community effective access to its data, resources and services in order to enable high-quality earth system research.

As “The Research University in the Helmholtz Association”, KIT creates and imparts knowledge for society and the environment. The aim is to make significant contributions to global challenges in the fields of energy, mobility and information. To this end, around 9,600 employees work together on a broad disciplinary basis in the natural, engineering, economic, humanities and social sciences. The KIT prepares its 23,300 students for responsible tasks in society, economy and science through a research-oriented university course. The innovation activity at KIT bridges the gap between knowledge and application for social benefit, economic prosperity and the preservation of our natural foundations of life.