Tara Shears, professor of particle physics, University of Liverpool.
"The one thing that terrified me as a child (and still does) is nuclear warfare. Public safety films in the 1970s and early 1980s were pretty scary anyway, but the programmes that described coldly and factually what would happen in the case of nuclear attack – the zones of various percentages of mortality around the hit, how to build your own nuclear shelter, how to purify your water, the various ways in which radiation would burn up your body, how people around you would just melt in the blast – these were more traumatic than anything else.
To this day I think about where I would hide in a building, and where best to be when close to a nuclear strike (I decided that it was better to be at the centre so you wouldn't have to know anything about it).
But how do you work out the best way to spend the last four minutes of your life when an attack is underway? I've never solved that one. And even though I'm a physicist with a much better understanding of risk and what would happen, I've never got over the horror that this could be unleashed by pressing a single button."
Richard Wiseman, professor of psychology, University of Hertfordshire.
"I am most afraid of being at a party and someone saying 'Can I tell you my dream?'"
Jonathan Overpeck, co-director of the Institute of the Environment, University of Arizona.
"After 35 years learning, researching and thinking about climate change around the globe, particularly focusing on all the climate changes that have occurred in the millennia prior to the last 100 years, I worry that the impacts of future anthropogenic climate change will be larger, more pervasive and costlier than most of my colleagues now believe. This scares me.
However, what scares me even more is that so many well-educated Americans choose to deny, doubt or ignore science when it is profitable or politically expedient for them. What this means for my country scares me the most."
Danielle Lee, TED Fellow and post-doctoral research associate, Department of Psychology, Cornell University.
"I'm afraid of antibiotic resistance, climate change, and environmental or natural disasters like so many people. But what shakes me is the sociological impact of ALL of these scary things. Urban and African-American communities are woefully under-served and these conversations aren't on many radars – and if they are aware of these issues, it falls way low. My communities just don't have a handle on these issues so we end up scrambling actually AFTER the blow has been dealt. The blow can be intense natural or environmental disaster (Hurricane Katrina), food security issues, emergency health response – it really doesn't matter. I'm scared to death that my communities aren't aware of these realities, aren't prepared for them, and don't have access to enough resources to survive them should an acute strike happen."
Andrea Sella, professor of inorganic chemistry, University College London.
"When I was born, CO2 levels stood at 318 parts per million (ppm). By the time I did work experience in secondary school, measuring CO2 in air samples, the level had risen to 330 and today we have exceeded 400 ppm. Our atmosphere is changing and with it are disappearing the glaciers in the Alps that I visited as a child, that my parents and grandparents climbed and skied on. It is an odd feeling to think of the landscape changing in my own lifetime, that those pristine valleys are not the same.
The baseline of my life has shifted. I'm 54, so retirement is not such a distant prospect. But I have children. So my time horizon is not 30-odd years but almost a century. What will their world be like? If heat waves in poor countries begin to hit 45 degrees C on a regular basis and food and fresh water get scarce, how many people will migrate across the globe? If the 100,000 that have been picked up in the Med so far this year can shift our politics and bring out the fearful fascist in so many of us, what will happen if the numbers really soar?
It's not the planet I worry about, it's society. It's the ties that bind us together. What will happen to communities, to infrastructure, and to supply chains when the going gets rough? What actions will individuals take, if the societal pie shrinks? What sort of society will my children live in when they reach middle age in the 2050s? That's what keeps me awake at night. After all, it's not a rehearsal."
Philip Moriarty, professor of physics, University of Nottingham.
"Here's what scares the bejaysus out of me… Deepak Chopra has 2.5 million followers on Twitter.
Let that sink in for a moment.
2.5 million people follow a man whose key talent is the ability to generate vacuous pseudoscientific bollocks-speak at a rate hitherto thought to be beyond human capability. His books sell bucket-loads, he's in huge demand as an 'inspirational' speaker, and even learned academics have urged us to take Chopra seriously.
As a scientist – indeed, as a human – I find this both rather depressing and deeply unnerving. The Chopra story is essentially a 21st-century reboot of The Emperor's New Clothes – a cautionary tale of the extent to which valueless pseudoscience can sweep the world."
Tim Goudge, postdoctoral fellow, Jackson School of Geosciences, The University of Texas at Austin.
"The thing that scares me most is the prospect of antibiotic- and antiviral-resistant disease strains, and the threat of global outbreaks of such diseases. I'm pretty sure that, at least for myself, this fear spawns from both reading and watching too much dystopian science fiction, as well as my general ineptitude in pathology and pathobiology.
I think one of the fascinating things about this fear is that it pits one's fear of disease against one's trust in modern medicine. While I do have a healthy dose of fear of the threat of global outbreak of a resistant 'superbug' disease strain (who wouldn't??), I also have confidence in the ability of those involved in medical science research to combat such diseases."
Melanie Okoro, water quality specialist, NOAA Fisheries West Coast Region.
"I'm not really scared of natural phenomena like hurricanes, tornadoes, or earthquakes – nothing I can really do to prevent them from happening. Plus, when you've lived in Alabama, you know there's nothing much to do but hunker down and wait it out.
As a scientist, what scares me the most is that we scientists may not be doing such a good job communicating scientific knowledge. Misinformation, when packaged up in a nice bow, can often trump good science. I'm scared we do more talking than listening. We have to continue to develop new ways in which to communicate science, through the transfer of ideas, education, and entertainment. Yes, science can be entertaining – and how we convey information is important.
We must communicate good science so that we grow and develop as a society, and preserve the knowledge for future generations. I'm scared that if we don't, the knowledge will be lost."
Hope Jahren, professor of geobiology, University of Hawaii at Manoa.
"I fear being misquoted on BuzzFeed, and having to spend the remainder of my career explaining the missing context."
Kelly Oakes is science editor for BuzzFeed and is based in London.
Contact Kelly Oakes at firstname.lastname@example.org.
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