Emergency medicine for our climate fever
-
0:01 - 0:05I'm here to talk to you about something
important that may be new to you. -
0:05 - 0:07The governments of the world
-
0:07 - 0:09are about to conduct
an unintentional experiment -
0:09 - 0:11on our climate.
-
0:11 - 0:16In 2020, new rules will require ships
to lower their sulfur emissions -
0:16 - 0:18by scrubbing their dirty exhaust
-
0:18 - 0:20or switching to cleaner fuels.
-
0:21 - 0:23For human health, this is really good,
-
0:23 - 0:26but sulfur particles
in the emission of ships -
0:26 - 0:28also have an effect on clouds.
-
0:29 - 0:31This is a satellite image of marine clouds
-
0:32 - 0:34off the Pacific West Coast
of the United States. -
0:34 - 0:38The streaks in the clouds
are created by the exhaust from ships. -
0:38 - 0:41Ships' emissions include
both greenhouse gases, -
0:41 - 0:44which trap heat over long periods of time,
-
0:44 - 0:47and particulates like sulfates
that mix with clouds -
0:47 - 0:49and temporarily make them brighter.
-
0:50 - 0:53Brighter clouds reflect
more sunlight back to space, -
0:53 - 0:54cooling the climate.
-
0:55 - 0:57So in fact,
-
0:57 - 1:00humans are currently running
two unintentional experiments -
1:00 - 1:01on our climate.
-
1:01 - 1:05In the first one, we're increasing
the concentration of greenhouse gases -
1:05 - 1:07and gradually warming the earth system.
-
1:08 - 1:11This works something like a fever
in the human body. -
1:11 - 1:15If the fever remains low,
its effects are mild, -
1:15 - 1:17but as the fever rises,
damage grows more severe -
1:17 - 1:19and eventually devastating.
-
1:20 - 1:22We're seeing a little of this now.
-
1:23 - 1:24In our other experiment,
-
1:24 - 1:27we're planning to remove
a layer of particles -
1:27 - 1:30that brighten clouds and shield us
from some of this warming. -
1:30 - 1:34The effect is strongest
in ocean clouds like these, -
1:34 - 1:39and scientists expect the reduction
of sulfur emissions from ships next year -
1:39 - 1:42to produce a measurable increase
in global warming. -
1:44 - 1:45Bit of a shocker?
-
1:46 - 1:50In fact, most emissions contain sulfates
that brighten clouds: -
1:50 - 1:53coal, diesel exhaust, forest fires.
-
1:54 - 1:58Scientists estimate that the total
cooling effect from emission particles, -
1:58 - 2:01which they call aerosols
when they're in the climate, -
2:01 - 2:06may be as much as all of the warming
we've experienced up until now. -
2:06 - 2:09There's a lot of uncertainty
around this effect, -
2:09 - 2:13and it's one of the major reasons
why we have difficulty predicting climate, -
2:13 - 2:17but this is cooling that we'll lose
as emissions fall. -
2:18 - 2:22So to be clear, humans
are currently cooling the planet -
2:23 - 2:27by dispersing particles
into the atmosphere at massive scale. -
2:27 - 2:30We just don't know how much,
and we're doing it accidentally. -
2:31 - 2:33That's worrying,
-
2:33 - 2:36but it could mean that we have
a fast-acting way to reduce warming, -
2:36 - 2:40emergency medicine
for our climate fever if we needed it, -
2:40 - 2:42and it's a medicine
with origins in nature. -
2:44 - 2:47This is a NASA simulation
of earth's atmosphere, -
2:47 - 2:50showing clouds and particles
moving over the planet. -
2:50 - 2:55The brightness is the Sun's light
reflecting from particles in clouds, -
2:55 - 2:59and this reflective shield
is one of the primary ways -
2:59 - 3:01that nature keeps the planet
cool enough for humans -
3:01 - 3:03and all of the life that we know.
-
3:04 - 3:09In 2015, scientists assessed possibilities
for rapidly cooling climate. -
3:09 - 3:12They discounted
things like mirrors in space, -
3:12 - 3:17ping-pong balls in the ocean,
plastic sheets on the Arctic, -
3:17 - 3:19and they found
that the most viable approaches -
3:20 - 3:24involved slightly increasing
this atmospheric reflectivity. -
3:24 - 3:29In fact, it's possible that reflecting
just one or two percent more sunlight -
3:29 - 3:31from the atmosphere
-
3:31 - 3:34could offset two degrees Celsius
or more of warming. -
3:36 - 3:39Now, I'm a technology executive,
not a scientist. -
3:39 - 3:42About a decade ago,
concerned about climate, -
3:42 - 3:46I started to talk with scientists about
potential countermeasures to warming. -
3:47 - 3:50These conversations grew
into collaborations -
3:50 - 3:52that became the Marine
Cloud Brightening Project, -
3:52 - 3:55which I'll talk about momentarily,
-
3:55 - 3:59and the nonprofit policy organization
SilverLining, where I am today. -
3:59 - 4:03I work with politicians, researchers,
-
4:03 - 4:05members of the tech industry and others
-
4:05 - 4:07to talk about some of these ideas.
-
4:08 - 4:11Early on, I met British
atmospheric scientist John Latham, -
4:11 - 4:14who proposed cooling the climate
the way that the ships do, -
4:14 - 4:17but with a natural source of particles:
-
4:17 - 4:19sea-salt mist from seawater
-
4:19 - 4:23sprayed from ships into areas
of susceptible clouds over the ocean. -
4:23 - 4:26The approach became known
by the name I gave it then, -
4:26 - 4:28"marine cloud brightening."
-
4:28 - 4:32Early modeling studies suggested
that by deploying marine cloud brightening -
4:32 - 4:36in just 10 to 20 percent
of susceptible ocean clouds, -
4:36 - 4:41it might be possible to offset
as much as two degrees Celsius's warming. -
4:41 - 4:44It might even be possible
to brighten clouds in local regions -
4:44 - 4:49to reduce the impacts caused
by warming ocean surface temperatures. -
4:49 - 4:52For example, regions
such as the Gulf Atlantic -
4:52 - 4:54might be cooled in the months
before a hurricane season -
4:54 - 4:57to reduce the force of storms.
-
4:57 - 5:01Or, it might be possible to cool waters
flowing onto coral reefs -
5:01 - 5:02overwhelmed by heat stress,
-
5:02 - 5:04like Australia's Great Barrier Reef.
-
5:04 - 5:07But these ideas are only theoretical,
-
5:07 - 5:10and brightening marine clouds
is not the only way -
5:10 - 5:13to increase the reflection
of the sunlight from the atmosphere. -
5:14 - 5:19Another occurs when large volcanoes
release material with enough force -
5:19 - 5:22to reach the upper layer
of the atmosphere, the stratosphere. -
5:23 - 5:26When Mount Pinatubo erupted in 1991,
-
5:26 - 5:28it released material
into the stratosphere, -
5:28 - 5:32including sulfates that mix
with the atmosphere to reflect sunlight. -
5:33 - 5:36This material remained
and circulated around the planet. -
5:37 - 5:41It was enough to cool the climate
by over half a degree Celsius -
5:41 - 5:43for about two years.
-
5:44 - 5:50This cooling led to a striking increase
in Arctic ice cover in 1992, -
5:50 - 5:54which dropped in subsequent years
as the particles fell back to earth. -
5:54 - 5:58But the volcanic phenomenon
led Nobel Prize winner Paul Crutzen -
5:58 - 6:01to propose the idea that dispersing
particles into the stratosphere -
6:02 - 6:05in a controlled way might be
a way to counter global warming. -
6:06 - 6:09Now, this has risks
that we don't understand, -
6:09 - 6:12including things like
heating up the stratosphere -
6:12 - 6:14or damage to the ozone layer.
-
6:14 - 6:18Scientists think that there could be
safe approaches to this, -
6:18 - 6:20but is this really where we are?
-
6:20 - 6:23Is this really worth considering?
-
6:23 - 6:25This is a simulation
-
6:25 - 6:27from the US National Center
for Atmospheric Research -
6:27 - 6:32global climate model showing,
earth surface temperatures through 2100. -
6:32 - 6:36The globe on the left visualizes
our current trajectory, -
6:36 - 6:40and on the right, a world where particles
are introduced into the stratosphere -
6:40 - 6:41gradually in 2020,
-
6:41 - 6:44and maintained through 2100.
-
6:44 - 6:48Intervention keeps surface temperatures
near those of today, -
6:48 - 6:52while without it, temperatures rise
well over three degrees. -
6:52 - 6:56This could be the difference
between a safe and an unsafe world. -
6:58 - 7:02So, if there's even a chance
that this could be close to reality, -
7:02 - 7:04is this something
we should consider seriously? -
7:06 - 7:08Today, there are no capabilities,
-
7:08 - 7:11and scientific knowledge
is extremely limited. -
7:11 - 7:16We don't know whether these types
of interventions are even feasible, -
7:16 - 7:18or how to characterize their risks.
-
7:19 - 7:22Researchers hope to explore
some basic questions -
7:22 - 7:26that might help us know
whether or not these might be real options -
7:26 - 7:28or whether we should rule them out.
-
7:29 - 7:32It requires multiple ways
of studying the climate system, -
7:32 - 7:35including computer models
to forecast changes, -
7:35 - 7:38analytic techniques like machine learning,
-
7:38 - 7:40and many types of observations.
-
7:41 - 7:42And though it's controversial,
-
7:42 - 7:47it's also critical that researchers
develop core technologies -
7:47 - 7:50and perform small-scale,
real-world experiments. -
7:51 - 7:55There are two research programs
proposing experiments like this. -
7:55 - 7:59At Harvard, the SCoPEx experiment
would release very small amounts -
8:00 - 8:05of sulfates, calcium carbonate and water
into the stratosphere with a balloon, -
8:05 - 8:08to study chemistry and physics effects.
-
8:09 - 8:10How much material?
-
8:11 - 8:14Less than the amount released
in one minute of flight -
8:14 - 8:15from a commercial aircraft.
-
8:16 - 8:18So this is definitely not dangerous,
-
8:18 - 8:20and it may not even be scary.
-
8:21 - 8:23At the University of Washington,
-
8:23 - 8:27scientists hope to spray
a fine mist of salt water into clouds -
8:27 - 8:30in a series of land and ocean tests.
-
8:30 - 8:33If those are successful,
this would culminate in experiments -
8:33 - 8:36to measurably brighten
an area of clouds over the ocean. -
8:37 - 8:41The marine cloud brightening effort
is the first to develop any technology -
8:41 - 8:45for generating aerosols for atmospheric
sunlight reflection in this way. -
8:45 - 8:48It requires producing
very tiny particles -- -
8:48 - 8:52think about the mist that comes
out of an asthma inhaler -- -
8:52 - 8:56at massive scale -- so think
of looking up at a cloud. -
8:56 - 8:59It's a tricky engineering problem.
-
8:59 - 9:01So this one nozzle they developed
-
9:01 - 9:04generates three trillion
particles per second, -
9:04 - 9:0680 nanometers in size,
-
9:06 - 9:07from very corrosive saltwater.
-
9:09 - 9:12It was developed by a team
of retired engineers in Silicon Valley -- -
9:12 - 9:14here they are --
-
9:14 - 9:19working full-time for six years,
without pay, for their grandchildren. -
9:19 - 9:22It will take a few million dollars
and another year or two -
9:22 - 9:26to develop the full spray system
they need to do these experiments. -
9:27 - 9:30In other parts of the world,
research efforts are emerging, -
9:30 - 9:35including small modeling programs
at Beijing Normal University in China, -
9:35 - 9:37the Indian Institute of Science,
-
9:37 - 9:42a proposed center for climate repair
at Cambridge University in the UK -
9:42 - 9:44and the DECIMALS Fund,
-
9:44 - 9:47which sponsors researchers
in global South countries -
9:47 - 9:50to study the potential impacts
of these sunlight interventions -
9:50 - 9:51in their part of the world.
-
9:52 - 9:56But all of these programs,
including the experimental ones, -
9:56 - 9:58lack significant funding.
-
9:59 - 10:02And understanding
these interventions is a hard problem. -
10:02 - 10:04The earth is a vast, complex system
-
10:04 - 10:07and we need major investments
in climate models, observations -
10:07 - 10:08and basic science
-
10:08 - 10:12to be able to predict climate
much better than we can today -
10:12 - 10:16and manage both our accidental
and any intentional interventions. -
10:18 - 10:19And it could be urgent.
-
10:20 - 10:24Recent scientific reports
predict that in the next few decades, -
10:24 - 10:27earth's fever is on a path to devastation:
-
10:27 - 10:29extreme heat and fires,
-
10:30 - 10:32major loss of ocean life,
-
10:33 - 10:35collapse of Arctic ice,
-
10:36 - 10:39displacement and suffering
for hundreds of millions of people. -
10:40 - 10:44The fever could even reach tipping points
where warming takes over -
10:44 - 10:46and human efforts are no longer enough
-
10:46 - 10:49to counter accelerating changes
in natural systems. -
10:50 - 10:52To prevent this circumstance,
-
10:52 - 10:55the UN's International Panel
on Climate Change predicts -
10:55 - 10:58that we need to stop
and even reverse emissions by 2050. -
10:59 - 11:04How? We have to quickly and radically
transform major economic sectors, -
11:04 - 11:08including energy, construction,
agriculture, transportation and others. -
11:09 - 11:13And it is imperative that we do this
as fast as we can. -
11:13 - 11:15But our fever is now so high
-
11:15 - 11:18that climate experts say
we also have to remove -
11:18 - 11:21massive quantities of CO2
from the atmosphere, -
11:21 - 11:24possibly 10 times
all of the world's annual emissions, -
11:24 - 11:26in ways that aren't proven yet.
-
11:27 - 11:31Right now, we have slow-moving solutions
to a fast-moving problem. -
11:32 - 11:34Even with the most optimistic assumptions,
-
11:34 - 11:37our exposure to risk
in the next 10 to 30 years -
11:37 - 11:40is unacceptably high, in my opinion.
-
11:41 - 11:44Could interventions like these
provide fast-acting medicine if we need it -
11:45 - 11:48to reduce the earth's fever
while we address its underlying causes? -
11:49 - 11:51There are real concerns about this idea.
-
11:51 - 11:55Some people are very worried
that even researching these interventions -
11:55 - 11:59could provide an excuse to delay efforts
to reduce emissions. -
11:59 - 12:01This is also known as a moral hazard.
-
12:02 - 12:04But, like most medicines,
-
12:04 - 12:07interventions are more dangerous
the more that you do, -
12:07 - 12:10so research actually
tends to draw out the fact -
12:10 - 12:13that we absolutely,
positively cannot continue -
12:13 - 12:16to fill up the atmosphere
with greenhouse gases, -
12:16 - 12:18that these kinds of alternatives are risky
-
12:18 - 12:21and if we were to use them,
-
12:21 - 12:23we would need to use
as little as possible. -
12:25 - 12:27But even so,
-
12:27 - 12:29could we ever learn enough
about these interventions -
12:29 - 12:31to manage the risk?
-
12:31 - 12:35Who would make decisions
about when and how to intervene? -
12:36 - 12:38What if some people are worse off,
-
12:38 - 12:40or they just think they are?
-
12:41 - 12:42These are really hard problems.
-
12:44 - 12:48But what really worries me
is that as climate impacts worsen, -
12:49 - 12:52leaders will be called on to respond
by any means available. -
12:53 - 12:56I for one don't want them to act
without real information -
12:56 - 12:58and much better options.
-
12:59 - 13:01Scientists think it will take
a decade of research -
13:01 - 13:03just to assess these interventions,
-
13:03 - 13:06before we ever were
to develop or use them. -
13:06 - 13:11Yet today, the global level of investment
in these interventions -
13:11 - 13:13is effectively zero.
-
13:14 - 13:17So, we need to move quickly
-
13:17 - 13:20if we want policymakers
to have real information -
13:20 - 13:22on this kind of emergency medicine.
-
13:24 - 13:25There is hope!
-
13:27 - 13:29The world has solved
these kinds of problems before. -
13:30 - 13:33In the 1970s, we identified
an existential threat -
13:33 - 13:35to our protective ozone layer.
-
13:36 - 13:38In the 1980s, scientists,
politicians and industry -
13:39 - 13:42came together in a solution to replace
the chemicals causing the problem. -
13:43 - 13:46They achieved this with the only
legally binding environmental agreement -
13:46 - 13:49signed by all countries in the world,
-
13:49 - 13:51the Montreal Protocol.
-
13:51 - 13:53Still in force today,
-
13:53 - 13:55it has resulted in a recovery
of the ozone layer -
13:55 - 13:58and is the most successful
environmental protection effort -
13:58 - 14:00in human history.
-
14:01 - 14:04We have a far greater threat now,
-
14:04 - 14:08but we do have the ability
to develop and agree on solutions -
14:08 - 14:10to protect people
-
14:10 - 14:12and restore our climate to health.
-
14:12 - 14:15This could mean that to remain safe,
-
14:15 - 14:18we reflect sunlight for a few decades,
-
14:18 - 14:21while we green our industries
and remove CO2. -
14:22 - 14:25It definitely means we must work now
-
14:25 - 14:29to understand our options
for this kind of emergency medicine. -
14:30 - 14:31Thank you,
-
14:31 - 14:36(Applause)
- Title:
- Emergency medicine for our climate fever
- Speaker:
- Kelly Wanser
- Description:
-
As we recklessly warm the planet by pumping greenhouse gases into the atmosphere, some industrial emissions also produce particles that reflect sunshine back into space, putting a check on global warming that we're only starting to understand. Climate activist Kelly Wanser asks: Can we engineer ways to harness this effect and further reduce warming? Learn about the promises and risks of "cloud brightening" -- and how it could help restore our climate to health.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 14:49
Brian Greene edited English subtitles for Kelly Wanser speaks at TEDSummit 2019 | ||
Oliver Friedman edited English subtitles for Kelly Wanser speaks at TEDSummit 2019 | ||
Oliver Friedman edited English subtitles for Kelly Wanser speaks at TEDSummit 2019 | ||
Oliver Friedman edited English subtitles for Kelly Wanser speaks at TEDSummit 2019 | ||
Oliver Friedman approved English subtitles for Kelly Wanser speaks at TEDSummit 2019 | ||
Oliver Friedman edited English subtitles for Kelly Wanser speaks at TEDSummit 2019 | ||
Krystian Aparta accepted English subtitles for Kelly Wanser speaks at TEDSummit 2019 | ||
Krystian Aparta edited English subtitles for Kelly Wanser speaks at TEDSummit 2019 |