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Turning knowledge of past climate change into action for the future

Arctic sea ice: Image credit NASA
It’s more helpful to talk about the things we can do, than the problems we have caused. 
Beth Shapiro, a molecular biologist and author of How To Clone A Mammoth, gave a hopeful response to an audience question about the recent UN report stating that one million species are threatened with extinction.

I arrived at the International Union for Quaternary Research (INQUA) 2019 conference, held in Dublin at the end of July, keen to learn exactly that: what climate scientists can do to mitigate the impact of our rapidly changing climate. INQUA brings together earth, atmosphere and ocean scientists studying the Quaternary, a period from 2.6 million years ago to the present day. The Quaternary has seen repeated and abrupt periods of climate change, making it the perfect analogue for our rapidly changing future.

In the case of extinctions, if we understand how species responded to human and environmental pressures in the past, we may be better equipped to protect them in the present day.

Protecting plants and polar bears

Heikki Seppä from the University of Finland and colleagues are using the fossil record to better understand how polar bears adapt to climate change. The Arctic bears survived the Holocene thermal maximum, between 10,000 and 6,000 years ago, when temperatures were about 2.5°C warmer than today. Although rising temperatures and melting sea ice drove them out of Scandinavia, fossil evidence suggests they probably found a cold refuge around northwest Greenland. This is an encouraging indicator that polar bears could survive the 1.5°C warming projected by the IPCC to occur sometime between 2030 and 2052, if it continues to increase at the current rate.

Protecting animal species means preserving habitat, so it’s just as important to study the effects of climate change on plants. Charlotte Clarke from the University of Southampton studies the diversity of plants during times of abrupt climate change, using Russian lake records. Her results show that although two thirds of Arctic plant species survived the same warm period which forced the bears to leave Scandinavia, they too were forced to migrate, probably moving upslope to colder areas.

If we understand how ecosystems respond to climate change, we will be better prepared to protect them in the future. But what will future climate change look like? Again, we can learn a lot by studying the past.

The past is the key to the future

To understand the impact of anthropogenic CO2 emissions on the climate, we must disentangle the effect of CO2 from other factors, such as insolation (radiation from the Sun reaching the Earth’s surface). This is the mission of Qiuzhen Yin from UC Louvain, Belgium, who is studying the relative impact of CO2 on climate during five past warm interglacials. Tim Shaw, from Nanyang Technological University in Singapore, presented work on the mechanisms driving past sea level change. And Vachel Carter from the University of Utah is using charcoal as an analogue for past fire activity in the Rocky Mountains. By studying the pattern of fire activity during past warm periods, we can determine which areas are most at risk in the future.
The 2018 fire season in Colorado was one of the worst on record.
So Quaternary scientists have a lot to tell us about what our rapidly changing planet might look like in the years to come. But how can we translate this information into practical action? ‘Science as a human endeavour necessarily encompasses a moral dimension’, says George Stone from Milwaukee Area Technical College, USA. Stone’s passionate call to action is part of a series of talks about how Quaternary climate research can be applied to societal issues in the 21st Century.

One thing scientists can do is try to engage with policymakers. Geoffrey Boulton of the International Science Council is hopeful that by partnering with INQUA and setting up collaborations with Quaternary scientists, it can help them do that. The International Science Council has a history of helping to integrate science into major global climate policy such as the Paris Agreement.

What can we do ourselves as scientists is to portray scientific results in a way that is visually appealing and easy to understand, so they are accessible to the public and to policymakers. Oliver Wilson and colleagues from the University of Reading are a prime example, as they brought along 3D printed giant pollen grains which they use for outreach and teaching as part of the 3D Pollen Project.
Given that it’s easier than ever to publicise your own results, through channels such as blogs and social media, hopefully a new generation of Quaternary scientists will leave inspired to engage in outreach and use their knowledge to make a difference.

This blog is written by Cabot Institute member Jen Saxby, a PhD student in the School of Earth Sciences at the University of Bristol.
Jen Saxby

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