No, I was polluting the atmosphere flying back from Denmark after a long-planned trip. If I had been in the United States I might have, but I saw the march more as an exercise for people who were upset, rather than something that was going to change policy. I don’t think it had any positive effect whatsoever on Trump. I’m also constantly requested to sign petitions. But I’m pretty doubtful that those things change anybody’s mind. I think win- ning elections is a lot more important than feel-good activities. How politically active do you think scientists should be?

彼得·阿格雷“赢得选举是很多比自我感觉良好的活动更重要。”美国总统唐纳德·特朗普(Donald Trump)将美国退出2015年巴黎气候协议的决定受到打击吗?


Climate change is different because the onset is not immediate. It’s the immediacy and the effect on the individual family mem- ber that make health threats a problem we

have to deal with right now?— as opposed to climate change, which will create prob- lems in a hundred years when everything will be different anyway. Geological time is beyond us. What can scientists in the United States do to engage the general public on climate change?

In the end, people will support action on climate change if they can understand it. I think more scientists should step up and go to the public?— but not to lecture people. To be morally correct is important, but to be convincing is more important. Sadly, scientists are not very good communicators, even of their own work to other scientists. They tend to overdo the minutiae and lose the importance of the topic. That’s a problem. It’s important to choose words carefully?— just talking about ‘natural selection’ rather than ‘evolution’, for example, can make it much easier to talk about anti- biotic resistance with elements of the religious right-wing. Communicating requires subtlety and sincerity. We could do a lot better.

彼得·阿格里(Peter Agre)是马里兰州巴尔的摩市约翰霍普金斯大学疟疾研究所的所长。

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I think some should run for public office. We have a dearth of elected representatives with scientific training, but they are very helpful. When the voting occurs, they’re in the room. Some have been very good. Rush Holt Jr was a physicist and an eight-term congressman; now he’s head of the American Association for the Advancement of Science. When he ran for office the bumper stickers in his New Jersey district said “My congressman is a rocket scientist”. He wasn’t?— he was a nuclear physicist?— but being a scientist was part of his platform. And Harold Varmus, he was very good. Varmus won the Nobel Prize in Physiology or Medicine in 1989, but he was an English major to begin with and he was articulate, precise and incredibly insight- ful. I think Varmus can be individually thanked for convincing then-President Bill Clinton to double the US National Institutes of Health budget when Varmus was director. We have to be careful not to overdo things?— sometimes I think too much visibility brings a lack of trust. But working with public figures is important, and maybe some of today’s young scientists will run for elected office. Twentyfive years from now, they could be in Congress and really able to do something positive. To put aside your science is a huge sacrifice, but there’ll be a reward. And the reward will be important for all of us. ■






JULIE FENTON Graduate student, Pennsylvania State University, USA It’s hard for scientists to make definitive statements about the ‘truth’. Just as we don’t believe exactly the same things as we did 50?years ago, we expect our understanding of the things we’re learning now will change over time. It doesn’t mean our current understanding should be dismissed as incomplete, but it can be a challenge to communicate this concept to non-scientists. It’s become evident that my communication skills are something I have to invest time in. It’s too easy to forget that we have a broader responsibility to the public. In my experience, public engagement is not a routine part of academic training. Every scientist can start by talking with people they know in their everyday lives. That’s not hard.


马里奥·莫利纳(MARIO MOLINA)“这已成为人们的信仰问题,但不合理。”



It is extraordinarily worrisome. Science tells us very clearly that we are putting mil- lions of people at very high risk if we continue to function in a business-as-usual manner. We don’t accept risk for people flying, or living in tall buildings in earthquake zones. But here we’re risking gigantic disasters for humanity. It is extremely irresponsible and unethical to neglect the welfare of future generations. Why has action on global warming been much harder to achieve than on ozone depletion?

Ozone depletion and climate change have some important differences. For one thing, there were a relatively small number of very large chemical companies involved in produc- ing the ozone-depleting compounds. Those companies were, of course, initially opposed to any regulation, but they were able to make alternative compounds that allowed us to con- tinue using refrigeration and aerosols without affecting the ozone layer. By contrast, climate change is tied to the use of fossil fuels. They’re pervasive and they’re crucial to the function- ing of society?— and therefore much harder to control. The other thing that happened is that the climate issue became politicized. Scepticism has become a mantra of the Republican party

in the United States, which currently holds the presidency, both houses of Congress and a majority of state legislatures. That unwilling- ness by a large part of the country’s political leadership to accept the reality of climate change makes the problem much more difficult to deal with. It’s become a matter of belief, however irrational. What can scientists do about it?

We normally think that the first step is to go to the people in power?— after all, they’re the ones who can implement the changes we need, so we should make sure they’re well informed. But this approach can backfire if you don’t do it in the proper way, and right now it is hard to see how the people in power in the United States can be convinced through rational argument. There are indications that rational thinking is taking a back seat in other parts of the world as well, and that’s extremely worrying. If scientists learned to communicate more effectively we might be able to affect govern- ment functions, but probably not in the near future. That doesn’t mean we should give up?— there are many organizations, such as city councils and industrial companies, that are continuing to behave rationally in spite of what is going on in the federal government?— but we do need to think about longer-term solu- tions. My expectation is that we will eventually deal with the problem through education, by communicating the enormous importance that science has and how it benefits society and our standard of living. ■ Mario Molina is professor of chemistry at the University of California, San Diego.


THOMAS GIANETTI,美国亚利桑那大学助理教授,在科学界和政治界之间,特别是在美国,存在着一条断裂,我认为我们有责任修复它。让更多的研究人员参与决策,即使是暂时的,也可能会有所帮助。但是,当您面对以特殊方式思考了40多年的人们时,很难改变主意。可能更聪明的是专注于教育和塑造年轻人的思想。我们还应该记住,围绕气候变化仍然存在许多技术挑战。例如,一氧化二氮是一种相对被忽视但非常有效的温室气体。我们需要更好地沟通,但是我们还有许多科学问题需要解决。

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activity. Such scientific arguments are not going to sway the Scott Pruitts of this world. But if we could develop climate-friendly technologies that are no more expensive than current tech- nology, the manufactured fear will disappear. What sort of technologies do you think are essential to reduce emissions?

We need electric vehicles with batteries that can be charged up for a 160-kilometre trip in 6?minutes. That’s one of my pet projects. If we can increase the energy density of electric vehicles threefold, at no additional cost, then electric vehicles will simply be a better choice for most people than internal-combustion engines. The current US administration wants to kill a lot of this applied research. As well as de-funding climate research, it has called for the elimination of the US Advanced Research Projects Agency–Energy (ARPA-E), which was founded during my time as energy secre- tary in the Obama administration. The House of Representatives went along with the cut, but the Senate wants to preserve the programme, so let’s hope that sanity prevails. A cynical view of what is happening is that new clean-energy technologies that are competitive, or better than competitive, with incumbent ways of generating energy are the last thing opponents of change want to see developed.




The Paris agreement is still an important signal of international consensus. With the Copenha- gen agreement in 2009, the developing world said to the rest of the world “you created this mess?— you fix it”. Now there is recognition that it is a world problem, and Europe and China are not going to pull back on their efforts to head off climate change just because the United States is trying to. There are too many engineers in the Chinese government for it to turn its back on scientific evidence. How have views on climate change become so polarized in the United States?

Al Gore took a strong public stance on climate change, and I admire that. But he is a promi- nent Democrat, and many Republicans have since made climate-change scepticism part of their political identity. Now we have a Repub- lican head of the US Environmental Protection Agency, Scott Pruitt, who simply doesn’t believe that the climate’s changing?— or if it is, that it’s not due to human actions. The other thing is that there are a lot of fake facts floating around


We can do better. Climate is a very complex thing to simulate. The failure to predict the global temperature plateau that we experienced from 2002 to 2012 was held up as proof that cli- mate scientists didn’t know what was going on. We now know that the models failed to accu- rately predict the subtle changes in warming of the deep oceans, although when averaged over two decades they were accurate. We’ve also underestimated the extent of many alarming changes, and it’s still hard to predict with any precision what’s going to hap- pen; the full effects of greenhouse-gas emis- sions won’t be seen for at least a hundred years. It’s like going to your doctor and saying “I’m 32?kilos overweight and I smoke, but unless you can predict exactly what’s going to happen to me and when, I’m not going to give up cheese- cake and cigarettes”. No patient would demand that of their doctor, so why should we demand it of climate scientists before we take action? What can scientists do to change things?


Yes. It’s especially useful to have scientists in cabinet-level positions. They are heads of agencies, they have budgets, and that allows them to do far more than any single senator or congressperson. When I became energy secretary in 2009, I was the first scientist to be a cabinet member in the history of the United States. I was very connected to the scientific world, so I was able to identify and recruit a lot of researchers who had never dreamed of joining the government. I spent a lot of time with them, not to micro- manage their decisions but to sit and brainstorm. My job was to bring in very good people, cover their backs and let them do their jobs. Do scientists have to drop their research to get involved in government?

I think most would have to. I was still a prac- tising scientist?— I couldn’t abandon my grad- uate students?— but it wasn’t easy. As then vice-president Joe Biden said to me, “You’re one sick puppy!” I was willing to spend vaca- tions and the wee hours of Saturday night working on research. But most people aren’t that crazy. ■ Steven Chu is professor of physics and molecular and cellular physiology at Stanford University, California. Interviews have been edited for length and clarity.

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