The world is getting warmer. The standard representation of the world getting warmer looks like this….
This graph is made from observations of the temperature all over the world. This isn’t the only evidence for global warming but that’s a story for another time.
My job title is (was until 2017) ‘attribution scientist.’ An attribution scientist looks at trends in the weather, or extreme weather events (e.g., floods, heatwaves, hurricanes) to see if there is any sign of changes over time. Temperature is an easy one, the graph above shows that the global temperature has risen over the past 100+ years. If I find a change I then have to figure out what causes that change, this is the ‘attribution’ step. For temperature it is fairly clear that human emissions have caused more heat to be trapped within the Earth’s atmosphere, so most, if not all, of the rise in temperature for the past 100+ years is attributable to human activities.
If the world is warming, does this mean that other types of weather will change? More heatwaves seems like an obvious outcome, but what about things like rain? If the world is warmer will everywhere get dryer or wetter? Physics says wetter, because a warmer atmosphere can hold more moisture and more heat means more evaporation. But will this be true everywhere? The main focus of my research is in changes in rainfall and rainfall-related events such as drought and flooding. In some areas flooding or drought have become more common occurrences recently, the question is, is this because of human induced global warming? And if so should we be expecting (and preparing for) more extreme weather in future?
Claire’s pages on climate change
What does climate change mean for the weather? (coming soon)
What’s the deal with climate models? What are they? Can we trust them? (coming soon)