Changing wet and dry seasons

The fickle nature of weather patterns is ultimately responsible for the where and when of tropical rainfall extremes which wreak damage on agriculture, infrastructure and people. Tropical cyclones, such as Enawo which battered Madagascar in March, can severely impact low-lying, highly populated regions through intense rainfall combined with strong winds and storm surges. Explosive thunderstorms operating at smaller spatial scales can generate flash flooding and may lead to devastating landslides in mountainous terrain. A sustained dearth of rainfall or multiple failed seasonal rains, as implicated in drought currently impacting Somalia, Kenya and Ethiopia, are also inextricably linked with evolving weather patterns, often driven by the slower heart-beat of the oceans as they pace out the internal rhythm of El Niño Southern Oscillation and its decadal counterparts. Continue reading Changing wet and dry seasons

Rapid increase in heat extremes in Europe

In the last few decades, Europe has warmed not only faster than the global average, but also faster than expected from anthropogenic greenhouse gas increases (van Oldenborgh et al., 2009). With the warming, Europe experienced record-breaking heat waves and extreme temperatures, such as the 2003 European heatwave, 2010 Russian heatwave, and 2015 European heatwave, which imposed disastrous impacts on individuals and society. Continue reading Rapid increase in heat extremes in Europe

Global temperature change as polka-dots

Inspired by National Geographic’s climate change evidence graphics, I made my own global temperature polka-dot visualisations.

In the spirit of experimentation, here are three types, successively getting more complicated. After comments from several people I have made both portrait & landscape versions. I would be interested to know which works best for you. Continue reading Global temperature change as polka-dots

Frost fairs and the Little Ice Age

The term ‘Little Ice Age’ refers to a period of cooler temperatures between around 1400 and 1850, although a range of dates are used. This climate feature has been inferred from various types of direct and indirect evidence, but it is still not clear how widespread these cooler temperatures were.

A new article by Lockwood et al explores some of the commonly used indirect evidence such as paintings and the occurrence of ‘frost fairs’ on the Thames. We also address the common assumption that the cooler temperatures were solely due to a reduction in solar activity (the Spörer and Maunder minima). Although this assumption is almost certainly wrong, the two features are sometimes considered to be synonymous.

Continue reading Frost fairs and the Little Ice Age