Climate research investigates the factors that influence the Earth’s climate systems and how these interact with human activities. It draws on multiple disciplines like atmospheric science, oceanography and geology to form a holistic view of how the climate system works and how that changes over time. Climate research is crucial in guiding international policy-making on how to slow and reverse harmful climate trends.
The international community has come to a broad consensus on anthropogenic climate change, but there remains significant uncertainty about how this is occurring and what impact it will have. This is partly due to the lack of controlled experimentation with our planet’s environment – we cannot simply turn off greenhouse gas (GHG) emissions and observe the results. As a result, climate scientists must work to identify correlations between observed data and GHG concentrations using a method called detection and attribution.
Observational data are extremely varied: they can be taken at land-based stations, ships and buoys in the ocean, on airplanes, on satellites that orbit the Earth, by drilling into ancient ice at the Earth’s poles, from tree rings, and many other sources. Because most observational data only cover a few hundred years at best and have patchy spatial distributions, climate scientists use sophisticated statistical methods to distinguish the signal of anthropogenic climate change from the noise of natural internal and external variability.
Models can help to disentangle these different sources of variation and predict how the global climate might evolve. In their simplest forms, these models describe the large-scale motions of air and water, which transport heat and shape paradigmatic climatic variables such as average surface temperature and rainfall. More complex models include representations of the full range of subsystem processes.