Beginning in 2012, and for many summers ever since, my team and I have been helicoptering onto the Greenland ice sheet, in this fantastical melt zone. We use helicopters to string cableways over the top of rushing super glacial rivers so that we can hang this river discharge measurement technology called Acoustic Doppler Current Profiler (ADCP). We operate around the clock to collect measurements of river discharge every hour, for up to a week in duration. We have collected the world's first meltwater runoff measurements on top of the ice sheet. What we then do is simultaneously use drones and satellites to map out the upstream contributing watershed area flowing to that point where we are collecting the discharge measurements. When we know the contributing watershed area and we have the flow measurements at the bottom of the watershed, we then have a completely independent field dataset from which we can test the ability of climate models to simulate meltwater runoff from the Greenland ice sheet. And it's those models that are being used to predict the future. It's those models that are being used to estimate projected ranges of sea level rise in IPCC reports and so forth.

LAURENCE C. SMITH is the John Atwater and Diana Nelson University Professor of Environmental Studies and Professor of Earth, Environmental and Planetary Sciences at Brown University. He is the author, most recently, of Rivers of Power. Laurence C. Smith's Edge Bio Page

I've been thinking about just how bright our future could be, how science knows almost no limits to what we could achieve, to the durations that we could last, to the portion of the cosmos that we could discover and explore, and to the heights of quality in each of our lives or the types of achievements we could make. . . . It's this vision of this wonderful and vast future that's at stake that inspires me to think more carefully about the risks we face now and the ways that we might imperil all of this with our actions. What things can only our generation or our children's generation do in order to protect this seed of humanity so that we can grow into something even more amazing, to protect our present and thereby protect our future?

TOBY ORD is a senior research fellow in philosophy at Oxford University and author of The Precipice: Existential Risk and the Future of Humanity. Toby Ord's Edge Bio Page

How do we understand that our 100,000-fold excess of numbers on this planet, plus what we do to feed ourselves, makes us a tumor on the body of the planet? I don't want the future that involves some end to us, which is a kind of surgery of the planet. That's not anybody's wish. How do we revert ourselves to normal while we can? How do we re-enter the world of natural selection, not by punishing each other, but by volunteering to take success as meaning success and survival of the future, not success in stuff now? How do we do that? We don't have a language for that.

ROBERT POLLACK is a professor of biological sciences, and also serves as director of the University Seminars at Columbia University (on sabbatical for academic year 2019-2020). He is the author of The Course of Nature, a book of drawings by the artist Amy Pollack, accompanied by his short explanatory essays. Robert Pollack's Edge Bio Page

Part of the definition of intelligence is always this representation model. . . . I’m pushing this idea of distribution—homeostatic surfing on worldly engagements that the body is always not only a part of but enabled by and symbiotic on. Also, the idea of adaptation as not necessarily defined by the consciousness that we like to fetishize. Are there other forms of consciousness? Here’s where the gut-brain axis comes in. Are there forms that we describe as visceral gut feelings that are a form of human consciousness that we’re getting through this immune brain?

CAROLINE A. JONES is a professor of art history in the Department of Architecture at MIT and author, most recently, of The Global Work of Art. Caroline Jones's Edge Bio Page

An even more recent and exciting revolution happening now is this connectomic revolution, where we’re able to map in exquisite detail the connections of a part of the brain, and soon even an entire insect brain. It’s giving us absolute answers to questions that we would have debated even just a few years ago; for example, does the insect brain work as an integrated system? And because we now have a draft of a connectome for the full insect brain, we can absolutely answer that question. That completely changes not just the questions that we’re asking, but our capacity to answer questions. There’s a whole new generation of questions that become accessible.

When I say a connectome, what I mean is an absolute map of the neural connections in a brain. That’s not a trivial problem. It's okay at one level to, for example with a light microscope, get a sense of the structure of neurons, to reconstruct some neurons and see where they go, but knowing which neurons connect with other neurons requires another level of detail. You need electron microscopy to look at the synapses.

ANDREW BARRON is the Australian Research Council Future Fellow and Deputy Head of the Department of Biological Sciences at Macquarie University. He is a neuroethologist with a particular focus on studying the neural mechanisms of honey bees. Andrew Barron's Edge Bio Page