Long-term Global Change
Human activities are now the major driver of changes in the atmosphere and its interactions with earth’s climate.
NCAS is investigating how our atmosphere and climate are changing, so that society has scientific evidence to inform adaptation and mitigation policies that respond to this unprecedented global challenge.
Our priority research activities address three key areas of scientific uncertainty, and make use of our modelling capabilities, our long-term observations of the atmosphere, and laboratory studies.
Scientists use numerical computer models to simulate the earth’s climate system and create projections of our future climate. However, climate projections are uncertain because we don’t know what man-made emissions will be in the future, and due to the difficulty in reducing the complex global climate system into mathematical equations.
NCAS are working to improve the robustness of climate projections. We will use the results from our UKESM modelling programme, which has created the UK’s first comprehensive Earth System Model, and we will compare our projections with other international Earth System models. We can also evaluate our model performances by looking at real-world measurements of the atmosphere, and comparing them to our computer simulated results.
Changes in atmospheric composition
The atmosphere is made up of many different gases. The most common gases are nitrogen, oxygen and argon. However, the atmosphere also contains some pollutants and greenhouse gases. The composition of the atmosphere determines its ability to trap heat, which can lead to long-term changes in our climate.
NCAS are looking at how changes in the composition of the stratosphere, the second layer of the earth’s atmosphere, will change in the future and how that might affect the troposphere, the first layer of the atmosphere and the air that we live in.
Changes in aerosols and clouds
Aerosols are tiny particles of liquid and solid suspended in the atmosphere. Alongside clouds they are a major factor in driving global and regional climate change because they change the way the sun’s energy is stored in our atmosphere.
NCAS are investigating changes in natural aerosols, such as volcanic ash or desert dust, and man-made aerosols, such as particles released by biomass burning. Scientists are trying to establish how different levels of aerosols affect cloud properties and rainfall levels.