Leif Speer
7th Grade, Honey Creek Middle School
Terre Haute, IN
Leif has always been passionate about climate change. He鈥檚 also passionate about science fair. 鈥淟ast year鈥檚 science project was the first time I really interacted with statistics, and I loved it,鈥� he says. 鈥淪o this year, I wanted to do a project that combined my work with the environment with my interest in stats and math.鈥� Inspired by his dad, who is a dendrochronologist (someone who studies past environments by studying tree rings), Leif decided to use tree ring records to look at climate in the Southern Hemisphere.
Dendroclimatic Reconstruction of the Southern Hemisphere
Project Background
Scientists have made historical temperature graphs using dendrochronology of the Northern Hemisphere. Those graphs show a 鈥渉ockey stick curve鈥� going up 鈥� evidence the climate is changing. But there was not yet a graph for the Southern Hemisphere, because there wasn鈥檛 a lot of data. Leif gathered data from 275 tree rings from the International Tree-Ring Databank and carefully checked their quality, eventually selecting 41 tree-ring sets from South America, Tasmania and New Zealand. He standardized them and ended up with 19 samples that could provide a graph from 500 CE to 2011 CE.
His graph showed that there was a major temperature increase during the past century compared to the 1400 years before it 鈥� evidence of climate change. But he did not see evidence of things like the Medieval Warm Period or the Little Ice Age, showing that the Southern Hemisphere had a slightly different climate from the Northern Hemisphere.
Beyond the Project
Leif is a passionate environmental activist and a member of an environmental group at his school: The EARTHlings. Together, they presented a climate resolution to their local city council. The resolution passed, and now Leif sits on the sustainability commission for the city of Terre Haute, making decisions about electric vehicle chargers and invasive species. He would like to be an environmental engineer. 鈥淚 think that the climate crisis is the biggest issue of our time, and I want to do all that I can in the fight against it,鈥� he says.
