Climate research aims to understand the long-term trends of Earth’s atmosphere and ocean, influencing ecosystems and human societies. PNNL scientists use a wide variety of techniques to gather data, from studying ice cores in the North and South poles to sampling air on airplanes or from satellites above the Earth to using high-performance computers to build models that predict changes to the climate. These technologies illuminate what is happening to our planet, how it will affect humans and wildlife and what can be done to slow harmful climate change trends or mitigate the impacts of a changing planet (Jahanzad et al. 2021).
The foundation of this work is a set of measurements called the global surface temperature record. These measurements are converted from absolute readings to temperature anomalies that are compared to historical averages across different locations and time periods. By this method, multiple groups of researchers from all over the world have independently discovered that global temperatures are rising.
The next step is to analyze what caused these temperature changes. While there is considerable uncertainty about exact future temperatures, we are able to make some educated guesses about the cause of this change through a set of methods known as “ensemble projections.” Statistical methodologies can then be used to estimate probabilities of how changes might impact the climate in the future. These probabilities have important implications for policymakers, who must weigh the tradeoffs between adaptation and mitigation in response to changing conditions (see Lemos et al. 2018).