[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.88,0:00:04.81,Default,,0000,0000,0000,,I'm here to talk to you about something\Nimportant that may be new to you.
Dialogue: 0,0:00:05.43,0:00:09.13,Default,,0000,0000,0000,,The governments of the world are about\Nto conduct an unintentional experiment
Dialogue: 0,0:00:09.13,0:00:10.66,Default,,0000,0000,0000,,on our climate.
Dialogue: 0,0:00:10.91,0:00:16.32,Default,,0000,0000,0000,,In 2020, new rules will require ships\Nto lower their sulfur emissions
Dialogue: 0,0:00:16.32,0:00:18.44,Default,,0000,0000,0000,,by scrubbing their dirty exhaust
Dialogue: 0,0:00:18.44,0:00:20.39,Default,,0000,0000,0000,,or switching to cleaner fuels.
Dialogue: 0,0:00:20.90,0:00:23.56,Default,,0000,0000,0000,,For human health, this is really good,
Dialogue: 0,0:00:23.56,0:00:25.95,Default,,0000,0000,0000,,but sulfur particles\Nin the emission of ships
Dialogue: 0,0:00:25.95,0:00:28.71,Default,,0000,0000,0000,,also have an effect on clouds.
Dialogue: 0,0:00:29.22,0:00:33.08,Default,,0000,0000,0000,,This is a satellite image of marine clouds
Dialogue: 0,0:00:33.08,0:00:35.01,Default,,0000,0000,0000,,off the Pacific West Coast\Nof the United States.
Dialogue: 0,0:00:35.01,0:00:38.34,Default,,0000,0000,0000,,The streaks in the clouds are created\Nby the exhaust from ships.
Dialogue: 0,0:00:38.34,0:00:41.10,Default,,0000,0000,0000,,Ships' emissions include\Nboth greenhouse gases,
Dialogue: 0,0:00:41.10,0:00:44.05,Default,,0000,0000,0000,,which trap heat over long periods of time,
Dialogue: 0,0:00:44.05,0:00:47.12,Default,,0000,0000,0000,,and particulates like sulfates\Nthat mix with clouds
Dialogue: 0,0:00:47.12,0:00:49.42,Default,,0000,0000,0000,,and temporarily make them brighter.
Dialogue: 0,0:00:49.92,0:00:53.19,Default,,0000,0000,0000,,Brighter clouds reflect\Nmore sunlight back to space,
Dialogue: 0,0:00:53.19,0:00:55.62,Default,,0000,0000,0000,,cooling the climate.
Dialogue: 0,0:00:55.62,0:00:57.74,Default,,0000,0000,0000,,So in fact,
Dialogue: 0,0:00:57.74,0:01:01.02,Default,,0000,0000,0000,,humans are currently running\Ntwo unintentional experiments
Dialogue: 0,0:01:01.02,0:01:01.97,Default,,0000,0000,0000,,on our climate.
Dialogue: 0,0:01:01.97,0:01:06.10,Default,,0000,0000,0000,,In the first one, we're increasing\Nthe concentration of greenhouse gases
Dialogue: 0,0:01:06.10,0:01:07.79,Default,,0000,0000,0000,,and gradually warming the Earth System.
Dialogue: 0,0:01:07.79,0:01:11.37,Default,,0000,0000,0000,,This works something like a fever\Nin the human body.
Dialogue: 0,0:01:11.37,0:01:14.54,Default,,0000,0000,0000,,If the fever remains low,\Nits effects are mild,
Dialogue: 0,0:01:14.54,0:01:18.04,Default,,0000,0000,0000,,but as the fever rises,\Ndamage grows more severe
Dialogue: 0,0:01:18.04,0:01:20.02,Default,,0000,0000,0000,,and eventually devastating.
Dialogue: 0,0:01:20.02,0:01:22.65,Default,,0000,0000,0000,,We're seeing a little of this now.
Dialogue: 0,0:01:22.65,0:01:24.35,Default,,0000,0000,0000,,In our other experiment,
Dialogue: 0,0:01:24.35,0:01:26.74,Default,,0000,0000,0000,,we're planning to remove\Na layer of particles
Dialogue: 0,0:01:26.74,0:01:29.97,Default,,0000,0000,0000,,that brighten clouds and shield us\Nfrom some of this warming.
Dialogue: 0,0:01:30.55,0:01:33.47,Default,,0000,0000,0000,,The effect is strongest\Nin ocean clouds like these
Dialogue: 0,0:01:33.47,0:01:39.43,Default,,0000,0000,0000,,and scientists expect the reduction\Nof sulfur emissions from ships next year
Dialogue: 0,0:01:39.43,0:01:42.28,Default,,0000,0000,0000,,to produce a measurable increase\Nin global warming.
Dialogue: 0,0:01:43.63,0:01:45.60,Default,,0000,0000,0000,,Bit of a shocker?
Dialogue: 0,0:01:45.60,0:01:50.03,Default,,0000,0000,0000,,In fact, most emissions contain sulfates\Nthat brighten clouds:
Dialogue: 0,0:01:50.03,0:01:53.88,Default,,0000,0000,0000,,coal, diesel exhaust, forest fires.
Dialogue: 0,0:01:53.88,0:01:58.11,Default,,0000,0000,0000,,Scientists estimate that the total\Ncooling effect from emission particles,
Dialogue: 0,0:01:58.11,0:02:00.96,Default,,0000,0000,0000,,which they call aerosols\Nwhen they're in the climate,
Dialogue: 0,0:02:00.96,0:02:05.84,Default,,0000,0000,0000,,may be as much as all of the warming\Nwe've experienced up until now.
Dialogue: 0,0:02:06.07,0:02:08.99,Default,,0000,0000,0000,,There's a lot of uncertainty\Naround this effect,
Dialogue: 0,0:02:08.99,0:02:13.39,Default,,0000,0000,0000,,and it's one of the major reasons\Nwhy we have difficulty predicting climate,
Dialogue: 0,0:02:13.39,0:02:17.40,Default,,0000,0000,0000,,but this is cooling that we'll lose\Nas emissions fall.
Dialogue: 0,0:02:18.18,0:02:21.92,Default,,0000,0000,0000,,So to be clear, humans\Nare currently cooling the planet
Dialogue: 0,0:02:21.92,0:02:26.78,Default,,0000,0000,0000,,by dispersing particles into\Nthe atmosphere at massive scale.
Dialogue: 0,0:02:26.78,0:02:29.81,Default,,0000,0000,0000,,We just don't know how much,\Nand we're doing it accidentally.
Dialogue: 0,0:02:30.39,0:02:32.18,Default,,0000,0000,0000,,That's worrying,
Dialogue: 0,0:02:32.18,0:02:36.20,Default,,0000,0000,0000,,but it could mean that we have\Na fast-acting way to reduce warming,
Dialogue: 0,0:02:36.20,0:02:39.76,Default,,0000,0000,0000,,emergency medicine for\Nour climate fever if we needed it,
Dialogue: 0,0:02:39.76,0:02:42.54,Default,,0000,0000,0000,,and it's a medicine\Nwith origins in nature.
Dialogue: 0,0:02:43.77,0:02:47.34,Default,,0000,0000,0000,,This is a NASA simulation\Nof Earth's atmosphere
Dialogue: 0,0:02:47.34,0:02:50.17,Default,,0000,0000,0000,,showing clouds and particles\Nmoving over the planet.
Dialogue: 0,0:02:50.17,0:02:54.51,Default,,0000,0000,0000,,The brightness is the Sun's light\Nreflecting from particles of clouds,
Dialogue: 0,0:02:54.51,0:03:01.64,Default,,0000,0000,0000,,and this reflective shield\Nis one of the primary ways
Dialogue: 0,0:03:01.70,0:03:03.16,Default,,0000,0000,0000,,that nature keeps the planet\Ncool enough for humans
Dialogue: 0,0:03:03.84,0:03:04.28,Default,,0000,0000,0000,,and all of the life that we know.
Dialogue: 0,0:03:04.28,0:03:08.75,Default,,0000,0000,0000,,In 2015, scientists assessed possibilities\Nfor rapidly cooling the climate.
Dialogue: 0,0:03:08.96,0:03:11.41,Default,,0000,0000,0000,,They discounted things\Nlike mirrors in space,
Dialogue: 0,0:03:11.41,0:03:14.26,Default,,0000,0000,0000,,ping-pong balls in the ocean,\Nplastic sheets on the Arctic,
Dialogue: 0,0:03:14.26,0:03:19.78,Default,,0000,0000,0000,,and they found that\Nthe most viable approaches
Dialogue: 0,0:03:19.78,0:03:23.85,Default,,0000,0000,0000,,involved slightly increasing\Nthis atmospheric reflectivity.
Dialogue: 0,0:03:24.61,0:03:28.99,Default,,0000,0000,0000,,In fact, it's possible that reflecting\Njust one or two percent more sunlight
Dialogue: 0,0:03:28.99,0:03:30.65,Default,,0000,0000,0000,,from the atmosphere
Dialogue: 0,0:03:30.65,0:03:34.35,Default,,0000,0000,0000,,could offset two degrees Celsius\Nor more of warming.
Dialogue: 0,0:03:35.80,0:03:39.46,Default,,0000,0000,0000,,Now, I'm a technology executive,\Nnot a scientist.
Dialogue: 0,0:03:39.46,0:03:42.01,Default,,0000,0000,0000,,About a decade ago,\Nconcerned about climate,
Dialogue: 0,0:03:42.01,0:03:46.43,Default,,0000,0000,0000,,I started to talk with scientists about\Npotential countermeasures to warming.
Dialogue: 0,0:03:47.25,0:03:50.13,Default,,0000,0000,0000,,These conversation grew\Ninto collaborations that became
Dialogue: 0,0:03:50.13,0:03:54.81,Default,,0000,0000,0000,,the Marine Cloud Brightening Project,\Nwhich I'll talk about momentarily,
Dialogue: 0,0:03:54.81,0:03:58.86,Default,,0000,0000,0000,,and the non-profit policy organization\NSilver Lining, where I am today.
Dialogue: 0,0:03:59.72,0:04:03.19,Default,,0000,0000,0000,,I work with politicians, researchers,
Dialogue: 0,0:04:03.19,0:04:05.29,Default,,0000,0000,0000,,members of the tech industry and others
Dialogue: 0,0:04:05.29,0:04:07.43,Default,,0000,0000,0000,,to talk about some of these ideas.
Dialogue: 0,0:04:08.24,0:04:11.44,Default,,0000,0000,0000,,Early on, I met British\Natmospheric scientist John Latham,
Dialogue: 0,0:04:11.44,0:04:14.30,Default,,0000,0000,0000,,who proposed cooling the climate\Nthe way that the ships do,
Dialogue: 0,0:04:14.30,0:04:16.78,Default,,0000,0000,0000,,but with a natural source of particles:
Dialogue: 0,0:04:16.78,0:04:19.13,Default,,0000,0000,0000,,sea salt mist from seawater
Dialogue: 0,0:04:19.58,0:04:23.23,Default,,0000,0000,0000,,sprayed from ships into areas\Nof susceptible clouds over the ocean.
Dialogue: 0,0:04:23.58,0:04:26.45,Default,,0000,0000,0000,,The approach became known\Nby the name I gave it then,
Dialogue: 0,0:04:26.45,0:04:28.25,Default,,0000,0000,0000,,marine cloud brightening.
Dialogue: 0,0:04:28.25,0:04:32.53,Default,,0000,0000,0000,,Early modeling studies suggested\Nthat by deploying marine cloud brightening
Dialogue: 0,0:04:32.53,0:04:36.27,Default,,0000,0000,0000,,in just 10 to 20 percent\Nof susceptible ocean clouds,
Dialogue: 0,0:04:36.27,0:04:41.19,Default,,0000,0000,0000,,it might be possible to offset\Nas much as two degrees Celsius of warming.
Dialogue: 0,0:04:41.40,0:04:45.05,Default,,0000,0000,0000,,It might even be possible\Nto brighten clouds in local regions
Dialogue: 0,0:04:45.05,0:04:48.96,Default,,0000,0000,0000,,to reduce the impacts caused\Nby warming ocean surface temperatures.
Dialogue: 0,0:04:48.96,0:04:51.76,Default,,0000,0000,0000,,For example, regions\Nsuch as the Gulf Atlantic
Dialogue: 0,0:04:51.76,0:04:54.30,Default,,0000,0000,0000,,might be cooled in the months\Nbefore a hurricane season
Dialogue: 0,0:04:54.30,0:04:56.77,Default,,0000,0000,0000,,to reduce the force of storms.
Dialogue: 0,0:04:56.77,0:05:00.75,Default,,0000,0000,0000,,Or, it might be possible to cool waters\Nflowing onto coral reefs
Dialogue: 0,0:05:00.75,0:05:03.22,Default,,0000,0000,0000,,overwhelmed by heat stress,\Nlike Australia's Great Barrier Reef.
Dialogue: 0,0:05:03.22,0:05:07.09,Default,,0000,0000,0000,,But these ideas are only theoretical,
Dialogue: 0,0:05:07.09,0:05:10.88,Default,,0000,0000,0000,,and brightening marine clouds\Nis not the only way
Dialogue: 0,0:05:10.88,0:05:14.26,Default,,0000,0000,0000,,to increase the reflection\Nof the sunlight from the atmosphere.
Dialogue: 0,0:05:14.26,0:05:19.76,Default,,0000,0000,0000,,Another occurs when large volcanoes\Nrelease material with enough force
Dialogue: 0,0:05:19.76,0:05:22.98,Default,,0000,0000,0000,,to reach the upper layer\Nof the atmosphere, the stratosphere.
Dialogue: 0,0:05:22.98,0:05:25.55,Default,,0000,0000,0000,,When Mount Pinatubo erupted in 1991,
Dialogue: 0,0:05:25.55,0:05:28.78,Default,,0000,0000,0000,,it released material into\Nthe stratosphere including sulfates
Dialogue: 0,0:05:28.78,0:05:33.21,Default,,0000,0000,0000,,that mix with the atmosphere\Nto reflect sunlight.
Dialogue: 0,0:05:33.21,0:05:36.50,Default,,0000,0000,0000,,This material remained\Nand circulated around the planet.
Dialogue: 0,0:05:36.50,0:05:41.30,Default,,0000,0000,0000,,It was enough to cool the climate\Nby over half a degree Celsius
Dialogue: 0,0:05:41.30,0:05:44.28,Default,,0000,0000,0000,,for about two years.
Dialogue: 0,0:05:44.28,0:05:50.40,Default,,0000,0000,0000,,This cooling led to a striking increase\Nin Arctic ice cover in 1992,
Dialogue: 0,0:05:50.40,0:05:54.33,Default,,0000,0000,0000,,which dropped in subsequent years\Nas the particles fell back to the Earth,
Dialogue: 0,0:05:54.33,0:05:58.39,Default,,0000,0000,0000,,but the volcanic phenomenon\Nled Nobel Prize Winner Paul Crutzen
Dialogue: 0,0:05:58.39,0:06:01.97,Default,,0000,0000,0000,,to propose the idea that dispersing\Nparticles into the stratosphere
Dialogue: 0,0:06:01.97,0:06:06.56,Default,,0000,0000,0000,,in a controlled way might be\Na way to counter global warming.
Dialogue: 0,0:06:06.56,0:06:09.99,Default,,0000,0000,0000,,Now, this has risks\Nthat we don't understand,
Dialogue: 0,0:06:09.99,0:06:11.87,Default,,0000,0000,0000,,including things like\Nheating up the stratosphere
Dialogue: 0,0:06:11.87,0:06:14.21,Default,,0000,0000,0000,,or damage to the ozone layer.
Dialogue: 0,0:06:14.21,0:06:17.49,Default,,0000,0000,0000,,Scientists think that there\Ncould be safe approaches to this,
Dialogue: 0,0:06:17.49,0:06:20.96,Default,,0000,0000,0000,,but is this really where we are?
Dialogue: 0,0:06:20.96,0:06:22.81,Default,,0000,0000,0000,,Is this really worth considering?
Dialogue: 0,0:06:22.81,0:06:24.86,Default,,0000,0000,0000,,This is a simulation
Dialogue: 0,0:06:24.86,0:06:27.81,Default,,0000,0000,0000,,from the US National Center\Nfor Atmospheric Research
Dialogue: 0,0:06:27.81,0:06:31.75,Default,,0000,0000,0000,,Global Climate Model showing\NEarth surface temperatures through 2100.
Dialogue: 0,0:06:31.75,0:06:36.16,Default,,0000,0000,0000,,The globe on the left visualizes\Nour current trajectory,
Dialogue: 0,0:06:36.16,0:06:39.43,Default,,0000,0000,0000,,and on the right, a world where particles\Nare introduced into the stratosphere
Dialogue: 0,0:06:39.43,0:06:41.39,Default,,0000,0000,0000,,gradually in 2020
Dialogue: 0,0:06:41.39,0:06:43.32,Default,,0000,0000,0000,,and maintained through 2100.
Dialogue: 0,0:06:43.32,0:06:47.13,Default,,0000,0000,0000,,Intervention keeps surface temperatures\Nnear those of today,
Dialogue: 0,0:06:47.13,0:06:53.14,Default,,0000,0000,0000,,while without it temperatures rise\Nwell over three degrees.
Dialogue: 0,0:06:53.14,0:06:56.51,Default,,0000,0000,0000,,This could be the difference\Nbetween a safe and an unsafe world.
Dialogue: 0,0:06:57.55,0:07:01.88,Default,,0000,0000,0000,,So, if there's even a chance\Nthat this could be close to reality,
Dialogue: 0,0:07:01.88,0:07:06.04,Default,,0000,0000,0000,,is this something\Nwe should consider seriously?
Dialogue: 0,0:07:06.04,0:07:09.66,Default,,0000,0000,0000,,Today, there are no capabilities
Dialogue: 0,0:07:09.66,0:07:11.62,Default,,0000,0000,0000,,and scientific knowledge\Nis extremely limited.
Dialogue: 0,0:07:11.62,0:07:15.82,Default,,0000,0000,0000,,We don't know whether these types\Nof interventions are even feasible,
Dialogue: 0,0:07:15.82,0:07:19.15,Default,,0000,0000,0000,,or how to characterize their risks.
Dialogue: 0,0:07:19.15,0:07:22.00,Default,,0000,0000,0000,,Researchers hope to explore\Nsome basic questions
Dialogue: 0,0:07:22.00,0:07:24.36,Default,,0000,0000,0000,,that might help us know
Dialogue: 0,0:07:24.36,0:07:26.31,Default,,0000,0000,0000,,whether or not these might be real options
Dialogue: 0,0:07:26.31,0:07:28.40,Default,,0000,0000,0000,,or whether we should rule them out.
Dialogue: 0,0:07:28.40,0:07:31.99,Default,,0000,0000,0000,,It requires multiple ways\Nof studying the climate system
Dialogue: 0,0:07:31.99,0:07:36.00,Default,,0000,0000,0000,,including computer models\Nto forecast changes,
Dialogue: 0,0:07:36.00,0:07:37.78,Default,,0000,0000,0000,,analytic techniques like machine learning,
Dialogue: 0,0:07:37.78,0:07:40.95,Default,,0000,0000,0000,,and many types of observations.
Dialogue: 0,0:07:40.95,0:07:42.38,Default,,0000,0000,0000,,And though it's controversial,
Dialogue: 0,0:07:42.38,0:07:46.91,Default,,0000,0000,0000,,it's also critical that researchers\Ndevelop core technologies
Dialogue: 0,0:07:46.91,0:07:51.28,Default,,0000,0000,0000,,and perform small-scale\Nreal world experiments.
Dialogue: 0,0:07:51.28,0:07:57.12,Default,,0000,0000,0000,,There are two research programs\Nproposing experiments like this.
Dialogue: 0,0:07:57.12,0:08:00.72,Default,,0000,0000,0000,,At Harvard, the SCoPEx experiment\Nwould release very small amounts
Dialogue: 0,0:08:00.72,0:08:04.06,Default,,0000,0000,0000,,of sulfates, calcium carbonate, and water\Ninto the stratosphere with a balloon
Dialogue: 0,0:08:04.06,0:08:09.78,Default,,0000,0000,0000,,to study chemistry and physics effects.
Dialogue: 0,0:08:09.78,0:08:11.14,Default,,0000,0000,0000,,How much material?
Dialogue: 0,0:08:11.14,0:08:14.54,Default,,0000,0000,0000,,Less than the amount released\Nin one minute of flight
Dialogue: 0,0:08:14.54,0:08:15.75,Default,,0000,0000,0000,,from a commercial aircraft.
Dialogue: 0,0:08:15.75,0:08:17.81,Default,,0000,0000,0000,,So this is definitely not dangerous,
Dialogue: 0,0:08:17.81,0:08:21.39,Default,,0000,0000,0000,,and it may not even be scary.
Dialogue: 0,0:08:21.39,0:08:23.97,Default,,0000,0000,0000,,At the University of Washington,
Dialogue: 0,0:08:23.97,0:08:27.31,Default,,0000,0000,0000,,scientists hope to spray\Na fine mist of salt water into clouds
Dialogue: 0,0:08:27.31,0:08:30.50,Default,,0000,0000,0000,,in a series of land an ocean tests.
Dialogue: 0,0:08:30.50,0:08:32.78,Default,,0000,0000,0000,,If those are successful,\Nthis would culminate in experiments
Dialogue: 0,0:08:32.78,0:08:36.37,Default,,0000,0000,0000,,to measurably brighten\Nan area of clouds over the ocean.
Dialogue: 0,0:08:37.02,0:08:40.40,Default,,0000,0000,0000,,The marine cloud brightening effort\Nis the first to develop any technology
Dialogue: 0,0:08:40.40,0:08:45.07,Default,,0000,0000,0000,,for generating aerosols for atmospheric\Nsunlight reflection in this way.
Dialogue: 0,0:08:45.07,0:08:48.49,Default,,0000,0000,0000,,It requires producing\Nvery tiny particles --
Dialogue: 0,0:08:48.49,0:08:52.61,Default,,0000,0000,0000,,think about the mist that comes\Nout of an asthma inhaler --
Dialogue: 0,0:08:52.61,0:08:55.81,Default,,0000,0000,0000,,at massive scale -- so think\Nof looking up at a cloud.
Dialogue: 0,0:08:56.53,0:08:58.94,Default,,0000,0000,0000,,It's a tricky engineering problem.
Dialogue: 0,0:08:58.94,0:09:04.06,Default,,0000,0000,0000,,So this one nozzle the developed generates\Nthree trillion particles per second,
Dialogue: 0,0:09:04.06,0:09:06.01,Default,,0000,0000,0000,,80 nanometers in size,
Dialogue: 0,0:09:06.01,0:09:08.52,Default,,0000,0000,0000,,from very corrosive saltwater.
Dialogue: 0,0:09:08.52,0:09:12.65,Default,,0000,0000,0000,,It was developed by a team\Nof retired engineers in Silicon Valley --
Dialogue: 0,0:09:12.65,0:09:14.08,Default,,0000,0000,0000,,here they are --
Dialogue: 0,0:09:14.08,0:09:19.31,Default,,0000,0000,0000,,working full time for six years\Nwithout pay for their grandchildren.
Dialogue: 0,0:09:19.64,0:09:22.27,Default,,0000,0000,0000,,It will take a few million dollars\Nand another year or two
Dialogue: 0,0:09:22.27,0:09:26.75,Default,,0000,0000,0000,,to develop the full spray system\Nthey need to do these experiments.
Dialogue: 0,0:09:26.75,0:09:30.62,Default,,0000,0000,0000,,In other parts of the world,\Nresearch efforts are emerging,
Dialogue: 0,0:09:30.62,0:09:34.26,Default,,0000,0000,0000,,including small modeling programs\Nat Beijing Normal University in China,
Dialogue: 0,0:09:34.26,0:09:37.29,Default,,0000,0000,0000,,the Indian Institute of Science,
Dialogue: 0,0:09:37.29,0:09:42.05,Default,,0000,0000,0000,,a proposed center for climate repair\Nat Cambridge University in the UK,
Dialogue: 0,0:09:42.05,0:09:44.23,Default,,0000,0000,0000,,and the ?? Fund,
Dialogue: 0,0:09:44.23,0:09:46.90,Default,,0000,0000,0000,,which sponsors researchers\Nin Global South countries
Dialogue: 0,0:09:46.90,0:09:50.03,Default,,0000,0000,0000,,to study the potential impacts\Nof these sunlight interventions
Dialogue: 0,0:09:50.03,0:09:52.09,Default,,0000,0000,0000,,in their part of the world.
Dialogue: 0,0:09:52.09,0:09:54.34,Default,,0000,0000,0000,,But all of these programs,
Dialogue: 0,0:09:54.34,0:09:56.20,Default,,0000,0000,0000,,including the experimental ones,
Dialogue: 0,0:09:56.20,0:09:58.80,Default,,0000,0000,0000,,lack significant funding.
Dialogue: 0,0:09:58.80,0:10:01.74,Default,,0000,0000,0000,,And understanding these\Ninterventions is a hard problem.
Dialogue: 0,0:10:01.74,0:10:04.18,Default,,0000,0000,0000,,The Earth is a vast, complex system
Dialogue: 0,0:10:04.18,0:10:07.12,Default,,0000,0000,0000,,and we need major investments\Nin climate models, observations
Dialogue: 0,0:10:07.12,0:10:08.44,Default,,0000,0000,0000,,and basic science
Dialogue: 0,0:10:08.44,0:10:12.13,Default,,0000,0000,0000,,to be able to predict climate\Nmuch better than we can today
Dialogue: 0,0:10:12.13,0:10:16.94,Default,,0000,0000,0000,,and manage both our accidental\Nand any intentional interventions.
Dialogue: 0,0:10:16.94,0:10:19.39,Default,,0000,0000,0000,,And it could be urgent.
Dialogue: 0,0:10:19.39,0:10:24.33,Default,,0000,0000,0000,,Recent scientific reports predict\Nthat in the next few decades
Dialogue: 0,0:10:24.33,0:10:26.89,Default,,0000,0000,0000,,Earth's fever is on a path to devastation:
Dialogue: 0,0:10:26.89,0:10:29.28,Default,,0000,0000,0000,,extreme heat and fires,
Dialogue: 0,0:10:29.28,0:10:33.14,Default,,0000,0000,0000,,major loss of ocean life,
Dialogue: 0,0:10:33.14,0:10:35.100,Default,,0000,0000,0000,,collapse of Arctic ice,
Dialogue: 0,0:10:35.100,0:10:39.83,Default,,0000,0000,0000,,displacement and suffering\Nfor hundreds of millions of people.
Dialogue: 0,0:10:40.48,0:10:44.14,Default,,0000,0000,0000,,The fever could even reach tipping points\Nwhere warming takes over
Dialogue: 0,0:10:44.14,0:10:46.46,Default,,0000,0000,0000,,and human efforts are no longer enough
Dialogue: 0,0:10:46.46,0:10:50.10,Default,,0000,0000,0000,,to counter accelerating changes\Nin natural systems.
Dialogue: 0,0:10:50.10,0:10:52.34,Default,,0000,0000,0000,,To prevent this circumstance,
Dialogue: 0,0:10:52.34,0:10:55.01,Default,,0000,0000,0000,,the UN's International Panel\Non Climate Change predicts
Dialogue: 0,0:10:55.01,0:10:59.08,Default,,0000,0000,0000,,that we need to stop\Nand even reverse emissions by 2050.
Dialogue: 0,0:10:59.08,0:11:03.90,Default,,0000,0000,0000,,How? We have to quickly and radically\Ntransform major economic sectors,
Dialogue: 0,0:11:03.90,0:11:08.62,Default,,0000,0000,0000,,including energy, construction,\Nagriculture, transportation and others.
Dialogue: 0,0:11:08.62,0:11:13.67,Default,,0000,0000,0000,,And it is imperative that we do this\Nas fast as we can.
Dialogue: 0,0:11:13.67,0:11:15.74,Default,,0000,0000,0000,,But our fever is now so high
Dialogue: 0,0:11:15.74,0:11:17.94,Default,,0000,0000,0000,,that climate experts say\Nwe also have to remove
Dialogue: 0,0:11:17.94,0:11:20.61,Default,,0000,0000,0000,,massive quantities of CO2\Nfrom the atmosphere,
Dialogue: 0,0:11:20.61,0:11:24.05,Default,,0000,0000,0000,,possibly 10 times all of\Nthe world's annual emissions,
Dialogue: 0,0:11:24.05,0:11:26.80,Default,,0000,0000,0000,,in ways that aren't proven yet.
Dialogue: 0,0:11:26.80,0:11:32.18,Default,,0000,0000,0000,,Right now, we have slow-moving solutions\Nto a fast-moving problem.
Dialogue: 0,0:11:32.18,0:11:34.35,Default,,0000,0000,0000,,Even with the most optimistic assumptions,
Dialogue: 0,0:11:34.35,0:11:37.27,Default,,0000,0000,0000,,our exposure to risk\Nin the next 10 to 30 years
Dialogue: 0,0:11:37.27,0:11:40.38,Default,,0000,0000,0000,,is unacceptably high in my opinion.
Dialogue: 0,0:11:40.83,0:11:44.76,Default,,0000,0000,0000,,Could interventions like these\Nprovide fast-acting medicine if we need it
Dialogue: 0,0:11:44.76,0:11:48.31,Default,,0000,0000,0000,,to reduce the Earth's fever while we\Naddress its underlying causes?
Dialogue: 0,0:11:48.82,0:11:51.45,Default,,0000,0000,0000,,There are real concerns about this idea.
Dialogue: 0,0:11:51.45,0:11:54.71,Default,,0000,0000,0000,,Some people are very worried\Nthat even researching these interventions
Dialogue: 0,0:11:54.71,0:11:59.10,Default,,0000,0000,0000,,could provide an excuse to delay efforts\Nto reduce emissions.
Dialogue: 0,0:11:59.10,0:12:01.88,Default,,0000,0000,0000,,This is also known as a moral hazard.
Dialogue: 0,0:12:01.88,0:12:04.12,Default,,0000,0000,0000,,But like most interventions,
Dialogue: 0,0:12:04.12,0:12:07.40,Default,,0000,0000,0000,,interventions are more dangerous\Nthe more that you do,
Dialogue: 0,0:12:07.40,0:12:13.12,Default,,0000,0000,0000,,so research actually tends to draw out\Nthe fact that we absolutely positively
Dialogue: 0,0:12:13.12,0:12:15.94,Default,,0000,0000,0000,,cannot continue to fill up\Nthe atmosphere with greenhouse gases,
Dialogue: 0,0:12:15.94,0:12:18.30,Default,,0000,0000,0000,,that these kinds of alternatives are risky
Dialogue: 0,0:12:18.30,0:12:23.39,Default,,0000,0000,0000,,and if we were to use them we would need\Nto use as little as possible.
Dialogue: 0,0:12:24.95,0:12:27.21,Default,,0000,0000,0000,,But even so,
Dialogue: 0,0:12:27.21,0:12:29.73,Default,,0000,0000,0000,,could we ever learn enough\Nabout these interventions
Dialogue: 0,0:12:29.73,0:12:31.33,Default,,0000,0000,0000,,to manage the risk?
Dialogue: 0,0:12:31.33,0:12:35.43,Default,,0000,0000,0000,,Who would make decisions\Nabout when and how to intervene?
Dialogue: 0,0:12:35.43,0:12:40.94,Default,,0000,0000,0000,,What if some people are worse off,
Dialogue: 0,0:12:40.94,0:12:43.18,Default,,0000,0000,0000,,or they just think they are?
Dialogue: 0,0:12:43.18,0:12:44.55,Default,,0000,0000,0000,,These are really hard problems.
Dialogue: 0,0:12:44.55,0:12:46.50,Default,,0000,0000,0000,,But what really worries me
Dialogue: 0,0:12:46.50,0:12:48.70,Default,,0000,0000,0000,,is that as climate impacts worsen,
Dialogue: 0,0:12:48.70,0:12:52.42,Default,,0000,0000,0000,,leaders will be called on to respond\Nby any means available.
Dialogue: 0,0:12:53.04,0:12:55.89,Default,,0000,0000,0000,,I for one don't want them to act\Nwithout real information
Dialogue: 0,0:12:55.89,0:12:58.96,Default,,0000,0000,0000,,and much better options.
Dialogue: 0,0:12:58.96,0:13:00.100,Default,,0000,0000,0000,,Scientists think it will take\Na decade of research
Dialogue: 0,0:13:00.100,0:13:03.37,Default,,0000,0000,0000,,just to assess these interventions
Dialogue: 0,0:13:03.37,0:13:06.30,Default,,0000,0000,0000,,before we ever were\Nto develop or use them.
Dialogue: 0,0:13:06.30,0:13:10.89,Default,,0000,0000,0000,,Yet today, the global level of investment\Nin these interventions
Dialogue: 0,0:13:10.89,0:13:13.46,Default,,0000,0000,0000,,is effectively zero.
Dialogue: 0,0:13:13.46,0:13:17.25,Default,,0000,0000,0000,,So, we need to move quickly
Dialogue: 0,0:13:17.25,0:13:20.04,Default,,0000,0000,0000,,if we want policymakers\Nto have real information
Dialogue: 0,0:13:20.04,0:13:22.24,Default,,0000,0000,0000,,on this kind of emergency medicine.
Dialogue: 0,0:13:24.37,0:13:26.74,Default,,0000,0000,0000,,There is hope!
Dialogue: 0,0:13:26.74,0:13:29.83,Default,,0000,0000,0000,,The world has solved\Nthese kinds of problems before.
Dialogue: 0,0:13:29.83,0:13:33.08,Default,,0000,0000,0000,,In the 1970s, we identified\Nan existential threat
Dialogue: 0,0:13:33.08,0:13:35.34,Default,,0000,0000,0000,,to our protective ozone layer.
Dialogue: 0,0:13:35.34,0:13:38.63,Default,,0000,0000,0000,,In the 1980s, scientists,\Npoliticians and industry
Dialogue: 0,0:13:38.63,0:13:42.70,Default,,0000,0000,0000,,came together in a solution to replace\Nthe chemicals causing the problem.
Dialogue: 0,0:13:43.14,0:13:46.62,Default,,0000,0000,0000,,They achieved this with the only\Nlegally binding environmental agreement
Dialogue: 0,0:13:46.62,0:13:48.88,Default,,0000,0000,0000,,signed by all countries in the world,
Dialogue: 0,0:13:48.88,0:13:50.61,Default,,0000,0000,0000,,the Montreal Protocol.
Dialogue: 0,0:13:50.84,0:13:52.88,Default,,0000,0000,0000,,Still in force today,
Dialogue: 0,0:13:52.88,0:13:55.68,Default,,0000,0000,0000,,it has resulted in\Na recovery of the ozone layer
Dialogue: 0,0:13:55.68,0:13:58.47,Default,,0000,0000,0000,,and is the most successful\Nenvironmental protection effort
Dialogue: 0,0:13:58.47,0:14:00.08,Default,,0000,0000,0000,,in human history.
Dialogue: 0,0:14:01.07,0:14:03.83,Default,,0000,0000,0000,,We have a far greater threat now,
Dialogue: 0,0:14:03.83,0:14:08.18,Default,,0000,0000,0000,,but we do have the ability\Nto develop and agree on solutions
Dialogue: 0,0:14:08.18,0:14:09.70,Default,,0000,0000,0000,,to protect people
Dialogue: 0,0:14:09.70,0:14:12.54,Default,,0000,0000,0000,,and restore our climate to health.
Dialogue: 0,0:14:12.74,0:14:16.10,Default,,0000,0000,0000,,This could mean that to remain safe,
Dialogue: 0,0:14:16.10,0:14:17.86,Default,,0000,0000,0000,,we reflect sunlight for a few decades
Dialogue: 0,0:14:17.86,0:14:20.68,Default,,0000,0000,0000,,while we green our industries\Nand remove CO2.
Dialogue: 0,0:14:21.90,0:14:24.72,Default,,0000,0000,0000,,It definitely means we must work now
Dialogue: 0,0:14:24.72,0:14:29.80,Default,,0000,0000,0000,,to understand our options\Nfor this kind of emergency medicine.
Dialogue: 0,0:14:29.80,0:14:31.59,Default,,0000,0000,0000,,Thank you,
Dialogue: 0,0:14:31.59,0:14:35.91,Default,,0000,0000,0000,,(Applause)