Climate Diagnostics: The interplay of understanding and prediction
What are Climate Diagnostics, anyway? Most people hear the word "diagnosis" only when they go to the doctor. After taking your medical history, performing a physical examination and perhaps ordering some "diagnostic" lab tests, the doctor pronounces "You have the flu," or some other diagnosis. What we do at the ESRL/PSD Climate Diagnostics Branch is similar in many ways, only our "patient" is the Earth. Instead of taking the body temperature we analyze the air and water temperature. Instead of the blood pressure, we look at measurements of atmospheric pressure. We don't look for diseases, but rather we identify naturally recurring atmospheric and oceanic features such as El Niño. While medicine is based mostly on the biological sciences, we use the laws of physics and chemistry to study weather and climate. Climate diagnostics -- studies of the interrelationships among climate variables -- are what we use to make sense of the myriad observations of the atmosphere and oceans.
Why do we do climate diagnostics? The short answer is that it will lead to better predictions. Let's return to the doctor's office for a moment. After you are given your diagnosis you ask "What's the prognosis?" -- that is, "What is the future course of the illness?" In the same way, diagnostic studies of Earth's climate are closely related to prediction of the future climate. Without a good understanding of climate phenomena based on past observations we could not make good predictions of the future. And likewise, the conceptual and mathematical models we use for prediction help us gain a deeper understanding of present and past climates. That is why the mission of the Climate Diagnostics Branch is to improve both our understanding and prediction of Earth's climate.
A more technical description of the work at the Climate Diagnostics Branch can be found in our statement of mission and goals and in our Science Review document.