Live-tweeting a talk by @IceAgeEcologist on Ecological Respomsrs to Climate Change: Lessons from the Past 
Williams: Is 4 degrees C warming a lot? During the last ice age, a several-mile ice sheet covered North America, and it was only 4 degrees C colder. Earth definitely notices the difference!
Williams: Over the last 60 million years, the earth has been drifting from a greenhouse state with crocodiles living in Greenland, to an icehouse world with cycles of ice ages and permanent ice at the poles.
Williams: For the last 12,000 years of our interglacial warm period, Earth’s temperature has been pretty stable. This is the climate that human civilizations emerged in: agriculture, the first cities, and all human cultures.
Williams: During full glacial conditions, CO2 was 180 ppm. During typical interglacial warm periods, CO2 was about 290 ppm. Now? We’re about 415 ppm. We’ve exceeded the natural cycles of CO2 going back hundreds of thousands of years.
Williams: During the last deglaciation, Greenland ice cores record abrupt warming events of >10 degrees in 1-3 years (!). While current global warming is on the fast end of geologic history, the North Atlantic has experienced very fast rates of warming, and species survived!
Williams: Pollen recorded in lake cores shows us that when climates changed in the past, tree species shifted their ranges by hundreds of kilometers. That’s one way species can be resilient to warming—they love!
Williams: Species don’t move in lockstep: each has its own climate preferences. We can’t expect ecological communities to stay cohesive, and that’s ok. Species will reshuffle as climates change.
Williams: Only one North American plant species is known to have gone extinct, a species of spruce found in ice age fossil deposits the southeastern US. This tell us plants are superstars at climate resilience.
Williams: Big animals like mammoths, mastodons, North American horses and camels are the poster children of ice age extinction. Climate may have stressed these populations, but because almost only big animals died out, humans likely played the bigger role.
Williams: Climate change is now a big part of the international conscience: fires in Australia, droughts, melting ice sheets, heat waves, warm winters...people are noticing it in their back yards. And that’s with only one degree Celsius of warming in the last century!
Williams: Big and open data are hot now, but paleoecologists have been sharing data since the 1970’s. That’s because our data are hard-won and our questions are big. We’ve built @neotomadb to accumulate it: named after pack rats. They collect bits of the environment; so do we!
Williams: There’s a cool app that allows you to check out all the geologic and paleontology data as you drive or fly across the country: check out Flyover Country: flyovercountry.io
Williams: We have lots of information about a warming, changing world. So what can we do to slow down and adapt to warning world?
Williams: Focus on rates of change. Species can actually adapt or move, so long as climate doesn’t change too fast. Let’s keep climate change slow enough so that species can keep up. They’ve had practice.
Williams: If you read one book on climate solutions, get Drawdown. It’s got seven solutions for slowing climate change. drawdown.org/the-book
Williams: Vote climate! Tell your elected leaders that climate is an important issue to you. Personal action is important, but we really need action from the top.
Williams: Embrace assisted migration/managed relocation. Earth is a fragmented landscape. We can help species move to where they need to be to survive. Similarly, we can assist with evolution through selective breeding to spread resilient populations.
Williams: Don’t despair: our world is transforming, but we can bend the curve. Talk about climate change at home and in your communities, support science, get involved. We need each and every one of you!
Thanks to @IceAgeEcologist for a great talk, and for @UMaine, @MEScienceFest, and @SeaDogBangor for supporting this talk!
