WEBVTT 00:00:01.310 --> 00:00:05.306 What would the world look like if extreme climate change becomes reality? 00:00:05.330 --> 00:00:06.866 Well, here's just one example. 00:00:06.890 --> 00:00:10.046 If temperatures were to rise by three more degrees Celsius, 00:00:10.070 --> 00:00:13.056 Shanghai, a city of 24 million people in China, 00:00:13.080 --> 00:00:14.871 will be wiped off the map. 00:00:14.895 --> 00:00:16.896 And it's not just the only coastal city 00:00:16.920 --> 00:00:19.666 that's at risk of disappearing beneath rising sea levels. 00:00:19.690 --> 00:00:23.296 Globally, 2019 was the second hottest year on record. 00:00:23.320 --> 00:00:24.805 Cities all throughout the world 00:00:24.829 --> 00:00:27.166 experienced record-setting summer temperatures. 00:00:27.190 --> 00:00:30.536 In June 2019, temperatures in Churu, India, 00:00:30.560 --> 00:00:33.186 exceeded 120 degrees Fahrenheit, 00:00:33.210 --> 00:00:35.466 to the point that the government warned citizens 00:00:35.490 --> 00:00:39.757 to avoid drinking coffee, tea, and alcohol out of fear of overheating. 00:00:40.297 --> 00:00:44.986 Heat waves are becoming more severe and commonplace due to climate change, 00:00:45.010 --> 00:00:49.516 projected to lead to deaths at the same rate as all infectious diseases combined. 00:00:49.540 --> 00:00:50.714 This map here 00:00:50.738 --> 00:00:54.872 shows the increase in the severity and prevalence of heat waves 00:00:54.896 --> 00:00:57.717 if the world follows a moderate warming scenario. 00:00:57.741 --> 00:01:01.556 By 2050, summertime highs of 95 degrees Fahrenheit, 00:01:01.580 --> 00:01:03.160 or 35 degrees Celsius, 00:01:03.184 --> 00:01:05.771 will become the new normal in nearly 1,000 cities, 00:01:05.795 --> 00:01:09.753 triple the number of cities that currently experience these sweltering temperatures. 00:01:09.777 --> 00:01:13.317 But the irony is that cities are not just affected by climate change, 00:01:13.341 --> 00:01:15.006 they're also causing it. 00:01:15.030 --> 00:01:19.156 Cities consume between 60 and 80 percent of global energy resources 00:01:19.180 --> 00:01:23.686 and account for approximately 70 percent of global carbon dioxide emissions. 00:01:23.710 --> 00:01:25.406 As we can see here in this map, 00:01:25.430 --> 00:01:27.135 the light blue and the yellow areas 00:01:27.159 --> 00:01:29.722 correspond to those with the highest fossil fuel-based 00:01:29.746 --> 00:01:30.906 carbon dioxide emissions 00:01:30.930 --> 00:01:33.990 and also correspond to major urban centers. 00:01:34.452 --> 00:01:36.516 Aside from cities' energy consumption, 00:01:36.540 --> 00:01:39.156 growing urban areas convert the planet's green surfaces 00:01:39.180 --> 00:01:40.457 to buildings and pavement, 00:01:40.481 --> 00:01:42.786 and these can absorb more of the sun's energy 00:01:42.810 --> 00:01:45.750 than the natural grasslands and forests that they've replaced, 00:01:45.774 --> 00:01:48.686 making urban areas hotter than their surrounding environments. 00:01:48.710 --> 00:01:51.520 This phenomenon is called the "urban heat island effect." 00:01:51.544 --> 00:01:55.756 Here in Singapore, downtown neighborhoods can be as much as seven degrees Celsius, 00:01:55.780 --> 00:01:57.246 or 13 degrees Fahrenheit, 00:01:57.270 --> 00:01:59.846 hotter than the rainforests that were once here. 00:01:59.870 --> 00:02:02.976 While it's true that cities are contributing to climate change, 00:02:03.000 --> 00:02:07.186 they're also key actors in forging low carbon emission pathways. 00:02:07.210 --> 00:02:10.816 In dense cities like New York City and Tokyo, for instance, 00:02:10.840 --> 00:02:12.176 the average resident 00:02:12.200 --> 00:02:16.136 is responsible for over two tons of carbon dioxide emissions per capita. 00:02:16.160 --> 00:02:19.266 This is less than a single passenger car emits 00:02:19.290 --> 00:02:21.466 in a single year in the United States. 00:02:21.490 --> 00:02:24.569 Cities around the world are stepping up to tackle climate change, 00:02:24.593 --> 00:02:25.767 with ambitious policies 00:02:25.791 --> 00:02:28.746 that often exceed the requirements of national governments. 00:02:28.770 --> 00:02:30.616 Take Copenhagen, for example. 00:02:30.640 --> 00:02:33.808 It's committed to become carbon neutral by 2025, 00:02:33.832 --> 00:02:38.161 and Glasgow in Scotland also plans to become carbon neutral by 2030. 00:02:38.185 --> 00:02:41.649 Today, there are more than 10,000 cities all around the world 00:02:41.673 --> 00:02:44.451 that are committing to their own ambitious climate actions, 00:02:44.475 --> 00:02:46.846 plans that include emissions reduction targets, 00:02:46.870 --> 00:02:49.476 clean energy and sustainable transit projects, 00:02:49.500 --> 00:02:51.646 and also energy efficiency policies 00:02:51.670 --> 00:02:55.936 that can save people and cities money, energy, and emissions. 00:02:56.260 --> 00:02:59.196 Recent analysis shows that just 6,000 cities, 00:02:59.220 --> 00:03:01.086 combined with regions and companies, 00:03:01.110 --> 00:03:04.726 are undertaking climate initiatives that can reduce global emissions 00:03:04.750 --> 00:03:08.876 by up to two gigatons of carbon dioxide equivalent in 2030. 00:03:08.900 --> 00:03:12.486 That's roughly 4 percent of the world's total annual emissions 00:03:12.510 --> 00:03:14.796 on top of what national governments have pledged. 00:03:14.820 --> 00:03:16.266 And this is just the start. 00:03:16.290 --> 00:03:19.666 Imagine what could happen if 20,000 cities were to band together 00:03:19.690 --> 00:03:21.316 to curb climate change. 00:03:21.340 --> 00:03:24.766 While this potential for cities' climate action sounds really promising, 00:03:24.790 --> 00:03:26.506 cities must work to make sure 00:03:26.530 --> 00:03:29.476 that these policies are implemented fairly and equitably. 00:03:29.500 --> 00:03:32.176 Where you live in a city, your income, your race - 00:03:32.200 --> 00:03:33.403 research is showing 00:03:33.427 --> 00:03:36.926 that these factors can determine your access to environmental benefits 00:03:36.950 --> 00:03:39.009 like green space and sustainable transit, 00:03:39.033 --> 00:03:42.104 and they can also determine your share of environmental burdens 00:03:42.128 --> 00:03:44.076 like air pollution and climate change. 00:03:44.100 --> 00:03:46.304 We observe these neighborhood-level disparities 00:03:46.328 --> 00:03:49.541 particularly clearly in these side-by-side images of Los Angeles, 00:03:49.565 --> 00:03:52.716 comparing income on the left and tree cover on the right. 00:03:52.740 --> 00:03:55.676 The darkest green neighborhood has an average annual income 00:03:55.700 --> 00:03:58.246 of over 100,000 US dollars per person. 00:03:58.270 --> 00:04:00.916 And over 70 percent of it has tree cover. 00:04:00.940 --> 00:04:03.376 The blue neighborhoods towards the bottom of the map 00:04:03.400 --> 00:04:05.416 only have a third of the income per person 00:04:05.440 --> 00:04:07.656 and less than five percent tree cover. 00:04:07.680 --> 00:04:09.750 Seventy percent versus five. 00:04:10.160 --> 00:04:12.496 This disparity has real consequences. 00:04:12.520 --> 00:04:14.816 Green spaces are often public spaces, 00:04:14.840 --> 00:04:18.436 and they're known to be associated with social and economic well-being. 00:04:18.460 --> 00:04:21.746 They can also reduce crime and foster social cohesion. 00:04:21.770 --> 00:04:24.866 Trees also can help to filter harmful air pollution 00:04:24.890 --> 00:04:27.206 and provide evaporative cooling and shade 00:04:27.230 --> 00:04:29.756 and relief for some of these high temperatures. 00:04:29.780 --> 00:04:31.787 So not only are those poorer neighborhoods 00:04:31.811 --> 00:04:34.536 at a greater disadvantage from access to green space, 00:04:34.560 --> 00:04:37.813 but they're also more vulnerable to air pollution and climate change. 00:04:37.837 --> 00:04:40.420 We can observe particularly pronounced disparities 00:04:40.444 --> 00:04:42.466 in urban heat according to race. 00:04:42.490 --> 00:04:47.276 Our latest research shows that 97 percent of major urban areas in the United States 00:04:47.300 --> 00:04:50.596 are exposing Black populations and people of color 00:04:50.620 --> 00:04:53.586 to a full degree Celsius higher of urban heat 00:04:53.610 --> 00:04:55.062 than their white counterparts. 00:04:55.086 --> 00:04:58.387 Take a look at this map of my hometown of Greenville, South Carolina - 00:04:58.411 --> 00:05:01.496 unlike the name suggests it is not green for everyone. 00:05:01.520 --> 00:05:04.826 The hottest areas of the county shown on the map in red 00:05:04.850 --> 00:05:08.985 correspond with the highest percentages of Black and poor populations. 00:05:09.009 --> 00:05:11.405 And we're seeing similar patterns throughout cities 00:05:11.429 --> 00:05:13.196 all across the United States. 00:05:13.220 --> 00:05:14.786 To address these inequalities, 00:05:14.810 --> 00:05:17.756 cities are starting to strategize and develop plans 00:05:17.780 --> 00:05:20.206 that can ensure that climate benefits 00:05:20.230 --> 00:05:23.036 are provided to all of their citizens equally. 00:05:23.060 --> 00:05:26.556 Take Bogotá, the capital city of Colombia, for example. 00:05:26.580 --> 00:05:29.256 It has one of the most extensive bike networks 00:05:29.280 --> 00:05:30.671 in all of Latin America, 00:05:30.695 --> 00:05:34.228 connecting people to jobs, education centers, 00:05:34.252 --> 00:05:36.511 and recreational opportunities. 00:05:36.535 --> 00:05:42.122 A new bike highway project can allow for around 42,000 daily bicycle trips 00:05:42.146 --> 00:05:46.866 and potentially avoid 270,000 tons of greenhouse gas emissions. 00:05:46.890 --> 00:05:50.564 In Africa, where many cities lack universal access to electricity, 00:05:50.588 --> 00:05:54.336 mini-grids are providing approximately 73 million households 00:05:54.360 --> 00:05:55.896 with clean electricity. 00:05:55.920 --> 00:05:57.697 So as we can see from these examples, 00:05:57.721 --> 00:06:00.396 tackling climate change has to start in cities. 00:06:00.420 --> 00:06:03.340 Many cities are starting to flip the script on climate change, 00:06:03.364 --> 00:06:06.245 proving to be part of the solution and not just the problem, 00:06:06.269 --> 00:06:08.992 and bringing the kind of innovative solutions that we need 00:06:09.016 --> 00:06:11.295 for a more just and sustainable world. 00:06:11.935 --> 00:06:13.306 Thank you.