KOJO NNAMDIYou're tuned in to The Kojo Nnamdi Show on WAMU 88.5, welcome. For the first time in history scientists have linked daily weather patterns to human induced climate change on a global scale. So what are the local effects? Today, we're taking a look at flashfloods, heat waves and everything in between. We're looking at you mild winter weather. What does climate change mean for the future of the Washington region and how do we prepare for rising temperatures, stronger storms and heavier rainfall in the short and long term?

KOJO NNAMDIJoining us to discuss this is Jason Samenow. He is Weather Editor and Chief Meteorologist for The Washington Post Capital Weather Gang. Jason, good to see you again.

JASON SAMENOWGood morning -- or good afternoon. Good to see you.

NNAMDIAlso joining us in studio is Joanna Lewis, an Associate Professor of Energy and Environment at Georgetown University. She serves as Director of the Science, Technology and International Affairs Program. Joanna Lewis, thank you for joining us.

JOANNA LEWISThank you for having me.

NNAMDIIlissa Ocko is a Senior Climate Scientist for the Environmental Defense Fund. Ilisa, thank you for joining us.

ILISSA OCKOHi. Happy to be here.

NNAMDIAnd Kate Johnson is Chief of the Green Building and Climate Branch at the D.C. Department of Energy and the Environment. Kate, thank you for joining us.

KATE JOHNSONIt's a pleasure to be here.

NNAMDIJason, what can you tell us about this new study that found the fingerprint of climate change present in our daily weather patterns?

SAMENOWSure. So researchers were trying to tackle the question as to whether the signal of climate change has emerged from the noise in day to day weather. Historically when we've had extreme weather events, which have happened, climate scientists have typically been very careful to say, well, we can't blame any single weather event on climate change, but that climate change is changing the odds. This study using computer model analysis and so forth found that in everyday weather we can actually see that signal of climate change. It has emerged in regions and locations all around the world.

NNAMDIDo you think study holds water?

SAMENOWBased on the climate scientists our reporters spoke with they found the study to be quite credible. And I think if you just observe what's happening in so many parts of the world and all over the world in terms of how our weather patterns are changing I think it -- there's sort of a common sense check right there when we look at the changes in heat waves, when we look at the changes in heavy precipitation events, snowfall and so forth.

NNAMDIIlissa Ocko, this study in question was motivated in part by President Donald Trump's tweets about how cold weather in one location on one day can discredit global warming. How do you respond when someone, particularly someone in power makes a comment like that?

OCKOWell, there's so much variability in the weather all the time, but climate is the long term average of the weather. And so you can think of it when you're walking your dog. You're walking along the straight path and then your dog is meandering back and forth along your path. And that's kind of your weather. You know where you're going in your path. But you can't really predict exactly where your dog is going to go. And so when you're walking you could change trajectories and that's what's happening with the climate. And so it shifts the weather around that average.

NNAMDIIn other words the weather is like my dog. It just strays from the path from time to time. Jason, what effect is climate change having on weather in this Washington region?

SAMENOWThere are a lot of effects which are happening. I give an entire talk on this issue. But notably we did a story recapping the past decade in the Washington area and we've seen a remarkable increase in our warm weather extremes and our heat extremes. We had our three warmest years on record in the last decade. We had our four hottest summers in the last decade. You may remember 2010 we had 67 90-degree days that year, which was the most on record. This past summer we also had an unusually high number of 90-degree days.

SAMENOWSo we're seeing a big increase in our heat extremes, especially how warm it's staying at night in the city. In the past it was rare for the temperature to stay above 80 degrees at night in the heart of the summer, but now that's occurring practically every summer on numerous occasions. But we're seeing it in every season. We're seeing our winters warmer. We're seeing a decline in snowfall. In fact, our average snowfall in the D.C. area, the late 1800s and early 1900s was only in what was in the 18 to 22 inch range. Now we're down to about 15 or 16 inches on average. Of course, this year we've had hardly any.

NNAMDIJason, another study predicts that our mid-Atlantic climate will come to resemble Mississippi's, hotter, wetter and thick with mosquitos during the course of the next 60 years or so. Does that seem plausible to you?

SAMENOWI think it seems plausible. Depending on the study you look at I've seen projections liken our future climate to Atlanta. I've seen Raleigh. This particular study probably uses a more aggressive emissions scenario where we're not slowing down how much of this heat trapping or how many of these heat trapping gases we're adding into the atmosphere. So it's projecting more warming so that, yes, our climate looks -- or resembles more like places along the Gulf Coast like Mississippi.

SAMENOWBut we can certainly I think -- even under an intermediate emissions scenario expect at least four to six degrees Fahrenheit of warming here in the Washington region by later this century. That means our summers only get hotter. We see an increase in extreme precipitation events. So in many ways, yes, our climate in future decades will increasingly resemble areas farther to the South whether it's Atlanta or whether it's Mississippi.

NNAMDIIlissa Ocko, let's talk about this region, because you're a resident of Montgomery County, Maryland. What are some actions county officials are taking to combat and adapt to a warming climate?

OCKOSo the county is involved in this very extensive effort right now to determine ways to achieve their greenhouse gas targets. Within the next several years, they want to drastically reduce the greenhouse gas emissions from the county. So they have these targets that they've set for 2027 and 2035. And right now there are several work groups that are trying to figure out exactly how to achieve those by working on areas such as transportation and buildings, and then also working with community residents to have them really understand the magnitude of the problem and the behavioral changes that are needed in order to achieve these targets.

NNAMDIIs this happening any place else in the country? And if so, where, and where does it need to happen?

OCKOThere are counties and cities all across the entire country that are taking extreme actions to address climate change. It's pretty remarkable how much I hear every day about different actions being taken across the country. I mean, states like New Mexico and Colorado and New Jersey and Pennsylvania have new policies recently to reduce emissions. And even our professional sports teams like the New York Yankees and the Miami Dolphins are taking action to curve their emissions.

NNAMDIKate Johnson, let's talk D.C. You serve as Climate Chief at D.C.'s Department of Energy and the Environment. What did the most recent climate assessment tell us about the Washington region?

JOHNSONWell, I think it confirmed a lot of what we already knew was likely to happen as a result of climate change. So in a nutshell we describe climate change as making D.C. warmer, wetter and wilder.

NNAMDIThose are the three Ws.

JOHNSONThe three Ws. Yes, that's right. And we're already starting to see that as Jason said. In recent years we've had some of the hottest summers. We've had some of the wettest months on record. And just this past summer we saw the first ever flood emergency declaration in the District when we got a month of rainfall in less than an hour, and that has real implications for the city. And that's why we have a Climate Ready D.C. Plan to lay out how we can prepare for that.

NNAMDIIf you've called stay on the line. We will get to your calls. If the lines are busy shot us a tweet @kojoshow or email to kojo@wamu.org. You can also go to our website kojoshow.org. Join the conversation there. Jason Samenow, D.C. of course is a low lying delta city with much of the surrounding areas, Alexandria and Fairfax in particular, are prone to flooding. What does climate change mean for those places in particular?

SAMENOWSure. So as the planet continues to warm it means that ocean water warms up. It expands and it causes the ocean to rise. In addition, you have melting glaciers, you have melting ice sheets. That also adds to the sea level rise effect. And so we're already seeing it. We're seeing this increase in high tide flooding in our coastal zones, places like Annapolis, Georgetown, Old Town. And there are projections which are somewhat dyer, but actually plausible that by later this century we will have high tide flooding between every other day and every day in these coastal locations.

SAMENOWSo basically that means, you know, water rising up over streets if they're not protected. And flooding will line areas almost daily as a result of the projected sea level rise. And we've already seen this increase in high tide flooding by a factor of about two or three just in the last few decades.

NNAMDIJoanna Lewis, you were a lead author in the Intergovernmental Panel on Climate Change's Fifth Assessment Report focusing on policy outcomes and the role of cross border cooperation. What did you find? How effective are the policies that are already in place? And where is there room for improvement?

LEWISWell, I think that there's a lot of room for improvement. You know, in the international space countries have been meeting regularly, and, you know, we now have a global agreement on climate change, The Paris Agreement. But there's really much more to be done, because we're really in a world now where countries have committed to bottom up policies of what they plan to do. And this really comes down to implementation at the local level.

NNAMDII'm wondering what your thoughts are on the study we've discussed from Nature Climate Change, which it verified by subsequent work, but upend the narrative that daily weather is distinct from long term climate change.

LEWISWell, I think this is really one of the most exciting areas of climate science right now. What we call attribution science, which is really where scientists are trying to pinpoint the role that climate change plays in making weather events more likely and more severe. So this is a really, you know, rapidly changing area. The first paper came out only in 2004 and it found that scientists were able to show how the 2003 heatwave that killed over 10,000 people across Europe was essentially much more likely due to climate change. It doubled the risk of that event.

LEWISSo we now see studies coming out all the time that focus on these extreme weather events and try to pinpoint the exact role that climate change played. We now know, for example, that human caused climate change made the record rainfall that fell over Houston during Hurricane Harvey three times more likely and at least 15 percent more intense. We know for example the forest fires in Northern California that were experienced over the last two decades have essentially climate change doubled the land area affected.

LEWISAnd we have ongoing analysis looking at events like the Australian bushfires. So, you know, this paper is part of this new line of research. But it actually goes even a step further because it tries to focus not just on a specific extreme event, but it tries to draw a link between, you know, any single day of weather around the world and find you a climate signal in that.

NNAMDIOkay. Let's go to the telephones. We will start with Pete in Arlington, Virginia. Pete, you're on the air. Go ahead, please.

PETEHi, Kojo. I just wanted to share a story. I was a charter boat captain and commercial fisherman on Chesapeake Bay for 36 years before I moved on from that. But early on I distinctly remember working outside in short sleeves in February and remembering the stories of the old time watermen working with icicles hanging from the rigging and stuff like that and having to literally saw through ice to go catch oysters on the river. And I thought, wow. You know, there's something that's happening here. I had never even heard of climate change, but it was something that I noticed very early on.

PETEAnd now we've moved from that into, you know, noticeable changes in fish migration. And I'll leave it at that. It was a very seminal moment for me. It was like, okay. Something is different here. Something is happening.

NNAMDIJason Samenow, Pete seems to have personally lived the relationship between climate change and daily weather.

SAMENOWYeah. I mean, I think people, who have lived in the area for decades, they can see the changes whether it's lakes and rivers, which used to freeze during the winter are no longer freezing as often if at all. And, of course, we're seeing these unusually warm winter days becoming a lot more frequent. I mean, even just this winter since December first we've had 31 days where the temperature has exceeded 50 degrees. And our average temperature this time of year is, of course, in the low to mid-40s. And so we're just -- you know, every year is different. You know, we have cold winters. We have warm winters. But you have to look at the long term trend. And the long term trend in Washington's climate and in some many areas in almost every area across the globe is unmistakably upward. The last six years, the six warmest on record globally.

NNAMDIBefore we go to a break, I'd like to get your take, Ilissa Ocko, on what Joanna was talking about in terms of the extreme weather attribution events that we're talking about. She mentioned Australia. You agree?

OCKOYeah. Joanna was right on the mark with all of the recent advances in science and our ability to really understand the role of human caused climate change in playing a role in these events. You basically run these simulations where you have these worlds with and without humans. And you do it for specific scenarios where you would get a particular event like Hurricane Harvey and all the rainfall. And through doing that we're able to see how that event would have unfolded without human influence and then also with human influence. And as long as you have enough information on what the natural world would have looked like then you can figure out exactly how humans have modified that role, that event.

NNAMDIWhat do you think government officials should be doing to prepare for future extreme weather? And for that matter what should we be all doing? I'm Kojo Nnamdi?

NNAMDIWelcome back. We're talking about the relationship between daily weather and climate change with Kate Johnson, Chief of the Green Building and Climate Branch at D.C.'s Department of Energy and the Environment. Ilissa Ocko is a Senior Climate Scientist for the Environmental Defense Fund. Joanna Lewis is an Associate Professor of Energy and Environment at Georgetown University. She serves as Director of the Science, Technology and International Affairs Program. And Jason Samenow, you know, you hear him here a lot. He's Weather Editor and Chief Meteorologist for The Washington Post Capital Weather Gang.

NNAMDIWe talked before we went into the break about what people can do individually. So here's Michelle in Silver Spring, Maryland. Michelle, your turn.

MICHELLE (CALLER0Hi. Can you hear me?

NNAMDIYes, Michelle.

(CALLER0Okay, great. Yes, I'm involved in a program called Drawdown. I mean, I really appreciate all the science and what governments can do. But, you know, we need to step up. I mean, individuals at every level in, you know, in our workplaces, in our homes, our schools with our children. And Drawdown offers the hundred best solutions to, you know, reducing global warming through the emissions of these gases. And believe it or not, the number three thing on the list is food waste. So you can see that if it's food waste -- number four is plant based diets. There's things that everyone can do.

(CALLER0So everybody out there google Drawdown and there are many organizations and churches in the areas that are doing programs introducing people to Drawdown.

NNAMDIMichelle, thank you for ...

(CALLER0And I'm involved right now. I'm a composter. I'm involved in a local program here in Montgomery County where we're trying to do a large scale composting for an elementary school in the area.

NNAMDIThank you very much for sharing that with us. Now Michelle provides an answer. Melody has a question. Melody on the eastern shore, you're on the air. Go ahead, please.

MELODYThank you, Kojo. I've been living here on the eastern shore for 15 years. I'm surrounded by commodities farmers. But I'm a backyard vegetable gardener growing organically. So I appreciate the previous caller's comments. I grow native plants. And I have noticed over the last at least five years if not longer some of the effects of our increasingly hot or dry or exceedingly wet climate on own backyard. But I'm wondering on the level of what these farmers around me are doing. I don't see a lot of climate adaptation. And can you speak -- is it possible to speak to some of the effects that people growing some of our nation's food or animal feed stuff and the effects of climate on that. And thank you.

NNAMDIThank you very much. Anyone wants to speak to that? Jason Samenow.

SAMENOWYeah, I mean, I would just say that, you know, with climate changes we do expect growing zones and growing seasons to change. They're already changing. So farmers will have to adapt and potentially change the types of crops they grow. And obviously seriously consider the effects of changing weather on their agricultural practices. So I think obviously, Melody, what you're doing sounds like you're being very proactive and forward looking, which is the way to go, because I think if you want to continue to have reliable consistent agricultural yields you have to take weather and climate into account, and if you don't it will be costly.

NNAMDIAlisa writes on our Facebook page, "Is there a place where local people can record observations and maybe send photos when we see odd things like forsythia blooming in January, Robins visiting in January, azaleas showing a few flowers in December or February? A few years ago my lilac tree started sprouting new leaves in December next to rosebushes that still had not lost their flowers from the season before. So I started paying attention. These are the clues that things are changing in the here and now."

NNAMDIIs there a place that anyone knows of that you can send photos or observations? If we do find out, we will certain to respond and let you know on our Facebook page. Jason, let's talk about the global variability of climate change effects. How does what's happening to our region compare to what's happening in places we just discussed like Australia?

SAMENOWSure. So we're seeing certain trends, which are consistent more or less universally which is rising temperatures. There are few exceptions to that, but almost everywhere temperatures are increasing. Where we see the most variability or differences from region to region is in precipitation. On balance in a warmer climate you expect heavier precipitation, because evaporation speeds up. There's more water in the air for downpours to develop. However, in a warmer climate you also speed up the drying out of the land surface.

SAMENOWSo areas that are having droughts, the droughts become more intense and that's exactly what's happened in Australia, which just had its driest year on record in addition to its hottest year on record. And those conditions ...

NNAMDICould it ever get that bad here?

SAMENOWWe've seen, of course, in California, we've seen record drought there in recent years. So sometimes when you get into these weather patterns they become stagnant. They persist. And when you have a more extreme climate acting on top of that, which is accelerating evaporation, yes. If we got into a drought pattern here in Washington, because the climate is warmer, we would expect the drought conditions to be more intense potentially than they were in the past. Whether we would have a drought as intense as they're seeing in more arid parts of the world and in more arid parts of the country, that's hard to say, but we could certainly have more serious droughts in the future here in the D.C. area than we have historically because the climate is warmer.

NNAMDIIlissa Ocko, how does something like President Trump's recent repeal of pollution controls on American streams and wetlands end up driving climate change?

OCKOSo there is a lot of policies that are being rolled back by this current administration that are not good for the environment and can play out in a number of different ways. When you have different pollutants either for air quality or water quality that you are no longer making sure that they're below limits that they need to be then that can play a role in local biogeochemistry. It can create new pollutants that are either admitted to the atmosphere or are in the soils that can impact the land and ecosystems.

OCKOSo that doesn't answer your question, and I'm not sure exactly which type of pollution you were talking about. But there's so many different ways that pollution can contribute to environmental and also climate problems that it really depends on the specific pollution.

NNAMDIJoanna, you've worked on energy and climate issues in China for almost two decades, it's my understanding, and you've put a lot into the domestic policies China is now implementing. How does D.C. compare to China when it comes to climate change mitigation?

LEWISYeah, so, you know, I work in China because its size really makes it a fascinating laboratory to experiment with large scale deployment of clean energy technology. So, China is, you know, not only leading the world in manufacturing of these technologies, they're deploying them at a scale that we've sort of never been able to see before globally. And with that comes lots of learning about how we can actually power large parts of our country with renewable energy.

LEWISChina's also very vulnerable to the impacts of climate change, so they're at the frontlines of thinking about how to make their coastlines, where most of their population lives, where all their economic centers are. Most of their economic centers are much more resilient. And D.C. is really a leader, I think, in both areas, both in looking to promote clean energy, as well as starting to think about how to become more resilient to the impacts of climate change.

LEWISAnd I think the exciting thing is there's actually several technologies that we can be looking at that both make us more resilient to the impacts of climate change and help us reduce emissions, right. So, if we are, for example, promoting more solar energy on our homes and buildings, and we're doing this in a way where we can actually use that solar as backup power during severe weather events, for example, we're much more resilient, then, to climate impacts. And so there's several examples, I think, where we can do this to make our infrastructure more resilient, but also have lower emissions.

NNAMDIKate Johnson, thinking about the local effects of climate change, how can we be ready, as a city, to get people out of harm's way? What does D.C. need to be doing to adapt to climate change?

JOHNSONSo, a lot of the things that we're doing are just like we were talking about, things that help us both reduce pollution and prepare for climate change at the same time. Perhaps one of the best examples is trees. So, we all know that trees have a lot of wonderful benefits. And our tree-planting efforts are helping us prepare for climate change in a couple of ways. They help us manage rain from heavier rain events. They help keep the city cooler. And, also, if they're planted close to buildings can actually -- because they're shading those buildings -- lower the energy used. And so we're really trying to find solutions like that that can address multiple impacts of climate change at the same time, that they're also helping us reduce pollution.

NNAMDIWe got an email from Jen, who said: since Maryland seems to be seriously considering expanding the Beltway along Rock Creek Park, is anyone accounting for the number of trees that would be lost? Trees should be our first line of defense, and it makes no sense to remove them for a road. (laugh) Kate Johnson, what's the District doing to combat flooding and other catastrophic weather events?

JOHNSONSure. So, D.C. is susceptible to three different types of flooding. So, when we think about addressing flooding, we have to think about it in three different ways. One is from coastal flooding. So, that's where sea level rise really has an impact and, you know, a big coastal storm. And because our rivers are tidal, it can impact us just like cities that are closer to the coast. We have flooding from our rivers, so from the Potomac, the Anacostia and Rock Creek.

JOHNSONBut probably one type of flooding that we don't think about as much, but is directly impacted by climate change, is what we call interior flooding. The type of flooding that happens from a really heavy rain event that might flood streets and basements, and it's not necessarily tied to a river. And so you might not think of yourself as living in a flood-prone area. And, all of a sudden, you know, there's two feet of water in the street in front of your house.

JOHNSONSo, we're doing a lot to better understand that kind of flooding. We're investing in a project to actually map out and model that type of flooding for the first time in the District in hopes that we can start to identify areas where we need to expand the drainage infrastructure, whether that's through sort of traditional pipes, but also through green infrastructure and rain gardens and capturing more of that rainwater. So, that's the type of planning that we're doing, and we're taking into account the changes that we're seeing in weather patterns because of climate change.

NNAMDIWhat is the urban heat island effect, and what parts of the city are most impacted by it?

JOHNSONSo, the urban heat island effect refers to the fact that urban areas, cities like D.C., are hotter than the surrounding, more rural areas. And that's for a couple reasons. Primarily, it's because there's a lot of really dark surfaces in cities, our roads, our buildings. They trap a lot of heat, and so that's why when you watch local weather on the local news, you'll notice D.C. is always a few degrees warmer than the surrounding towns. That's because of the urban heat island effect.

JOHNSONAnd when we've looked at D.C., in particular, we've seen that some areas in the city, on really hot days, can be as much as 15 degrees hotter than some of our cooler areas, which tend to be, you know, around large parks with lots of green space.

NNAMDIHere, now, is Helena in Washington, D.C. Helena, you're on the air. Go ahead, please.

HELENAI'm Helen Zhatir, and I've been in Washington, D.C. since 1990. And what I can say is that our pollen season is longer and heavier every year. And so people who suffer with allergies and asthma have symptoms that are occupied more of the year, and are more severe now.

NNAMDICare to comment on that, Jason?

SAMENOWSure, yeah. That is a direct effect of the fact that our growing seasons are longer. Spring is coming earlier in the year. We've seen earlier bloom dates. Even the cherry blossoms here in D.C., they're blooming about five days earlier than they used to. And, on some of these warm days we see in the winter, we sometimes see the tree pollen count spiking abnormally early. Even in January and February, we start to see people who are sensitive to tree pollen starting to experience symptoms. So, that's perfectly consistent with what we expect in a warming climate, to see that growing season expand, and for pollen allergies to have a wider range in terms of seasonality.

NNAMDIIn January, you just described me. (laugh) Here is Mark, in Silver Spring, Maryland. Mark, you're on the air. Go ahead, please.

MARKYes, hi. Good afternoon. I think Puerto Rico and Hurricane Maria is a critical case study. What they found was that in September, October, in terms of excess deaths, over 86 percent of all deaths were for those greater than 60 years old. What's happening is when you get these natural disasters, those that are from the most vulnerable population are most likely to be adversely affected in extreme ways. And now, how extreme?

MARKThe number of people who died, based on three different studies, in that hurricane was approximately 3,000. That's the number that was killed on September 11th. So, it's critical to have a serious after-action, comprehensive plan in light of this. And despite all the resources that were directed, we had so many deaths and so much suffering.

NNAMDIThank you very much for your call. Joanna Lewis, when extreme weather events take place in places where there are a lot of people who are poor, then the effects are even that more harsh.

LEWISAbsolutely. And I think the caller points this out really clearly. And, you know, when you look around the world, particularly at, you know, places like Bangladesh, where much of the population lives below sea level and a lot of poorer countries are much more vulnerable. And they're the ones that are going to be affected the most from the impacts of climate change.

LEWISI think one of the interesting policy implications we're seeing of this new attribution science, which we're discussing today, is how, in the international climate negotiations, you actually have countries now looking at this research and saying, you know, if we can prove the effect of human induced climate change in a severe weather event, we can actually start to talk about questions of liability and compensation for these events.

LEWISAnd so, there's actually, you know, a set of meetings and negotiations right now on what we call loss and damage, which is about trying to use this attribution science to think about how we can help the poor, you know, parts of the world adapt to climate change and be more prepared for the risks and hazards that they will face.

NNAMDIGot to take a short break. When we come back, we will continue this conversation on extreme weather. I'm Kojo Nnamdi.

NNAMDIWelcome back to our conversation about the relationship between daily weather and climate change. Jason Samenow, tell me about two degrees Celsius. Why is this figure significant?

SAMENOWSure. So, two degrees Celsius is the number that climate scientists and policymakers came up with as the point at which -- it's sort of a threshold level at which the impacts of climate change start to become particularly dangerous concerning sort of like a tipping point. With climate change, which is more mild, there's a mix of winners and losers. Some areas benefit, some areas are harmed.

SAMENOWBut once you get over that two-degree-Celsius threshold, the literature shows that the impacts of climate change start to become more serious. Because it signifies a greater rate of climate change, and that's what scientists are really concerned. It's not so much the amount of warming, but it's the rate at which it's happening. And if we get to two degrees in, you know, the next 50 years, that would signify or rate a climate change which is such that we would start to see a lot of areas seeing a lot of negative effects all over the world, some of which may be irreversible or headed in that direction.

NNAMDIWe've heard from other climate reporters who bristle when people start to talk about, quote-unquote, "solving climate change." What's wrong with the framing of that conversation?

SAMENOWI think climate change is something that we can slow down, but we can't stop. So, this is an issue we need to try to manage. It's a risk management issue. We want to try to cope with the effects that are inevitable, that we can avoid, through adaptation. And we also want to try to slow it down through reducing emissions or mitigation.

SAMENOWAnd so the challenge with climate change is that there's some amount of climate change already baked into the system. So, we have to deal and cope with it, but, at the same time, if we want to reduce the risk of the worst impacts and the worst consequences, we have to slow it down so that the rate of warming is less, and the absolute amount of warming that we experience over a period of time is less, as well.

NNAMDIIlissa Ocko, do you see climate change as something that can be solved?

OCKOI agree with what Jason said, and I, too, don't like using the word solve, because we've already seen the climate warm by nearly two degrees Fahrenheit. And so what that means is that in order to get back to the preindustrial conditions where we didn't see this level of warming, that would be, essentially, solving climate change. And we're at a point where these greenhouse gases that we've emitted can stay in the atmosphere for decades and sometimes centuries.

OCKOAnd so we've committed ourselves to this level of warming, unless we really ramp up technologies to remove carbon dioxide from the atmosphere, which are promising and on the rise, but are not there yet. So, in that sense, we really want to slow down the rate of warming, want to limit the amount of warming we experience. Every incremental amount of warming matters.

OCKOTwo degrees is an important number. It's a number that, as modern humans, have never lived outside of the realm of more than two degrees Centigrade. So, it makes sense that that is the number we look at, but it by no means is a magic number. Every little bit of warming will have impact and so we want to slow our rate of emissions, eventually get them to zero, so that we prevent additional warming and additional consequences.

NNAMDIJoanna, climate change is something that can be solved?

LEWISWell, I think when we think about climate change, I mean, it's important to realize that, you know, there's not a sort of one-for-one relationship between emissions we put in the atmosphere and then the temperature and other extreme weather events that we see. And so for every sort of ton of carbon that we can take out of the atmosphere or avoid emitting in the first place, we're actually shifting our entire risk profile to move away from these sort of higher-end scenarios, you know, these doomsday scenarios of the world we could be in under extreme warming.

LEWISSo, I think that, you know, even small incremental changes that we make could be moving us away. We're essentially shifting our risk profile from these more catastrophic events. And that's really -- you know, these are the events that really can affect human lives and cost billions of dollars in damages.

NNAMDIWell, we had a caller earlier who wanted to know if there was a place she could send photos. And we got a response from Sarah, by way of email: Use Nature's Notebook app as a photo journal of plant and animal changes overtime like tree buds opening early. Your observations provide a good journal for you. And also going to Citizen Science database for scientists to study climate change effects. Back to the telephones, now. Here is Amanda in Poolesville, Maryland. Amanda, your turn.

AMANDAThanks, Kojo. I'm calling because I work for a project called The Million Acre Challenge. And I was listening to the caller talk about agriculture on the eastern shore. And I wanted to share that we at The Million Acre Challenge, along with the Maryland Department of Agriculture, are going to be working hard on creating resilience funds over the next decade trying to work with all kinds of funds to build their soil health, which will help them become more resilient, more profitable and draw down atmospheric carbon. So, the change is coming to help make agriculture a part of the solution, and we are really looking forward to it. And hope that other folks will join us in this as well.

NNAMDIWe got a tweet from Greg, who said: did you consider having a climate change denier on today's show? Greg, the answer to that would be no. But Jason Samenow, as someone who reports on climate change, do you worry about people tuning out, perhaps getting tired of all the doom and gloom?

SAMENOWYes. I mean, that is a concern that, you know, people will tune out if they feel hopeless. And I think a number of climate scientists and climate communicators who have looked at this issue have emphasized the importance of instilling hope when we're talking about climate change. That, you know, we're not doomed to a future which is terrible, that we have choices, we have solutions. There are things we can do to slow this down and to continue to have a livable planet, a sustainable planet.

SAMENOWSo, I think people do tend to shut down if all you tell them is that we can't slow this down. The impacts are catastrophic. Everyone's going to be harmed. So, I think you do want to give people solutions when you're communicating about climate change. And you do obviously want to convey an optimistic message, even though there are a lot of concerns, obviously.

NNAMDIIlissa, you research climate change mitigation. What do we need to do to reduce global warming in the short term?

OCKOSo, there are a lot of different greenhouse gases that contribute to climate change. The main one we hear about all the time is carbon dioxide. And emissions of carbon dioxide contribute to around half of the warming we're experiencing today. But around a quarter of the warming we're experiencing today is from a greenhouse gas called methane, which a lot of people are familiar with, as well.

OCKOAnd methane is powerful at trapping heat, but it doesn't last for very long in the atmosphere. And so it offers a really promising opportunity to limit warming in the near term, because it is absolutely driving the rate of warming over the next 10, 20 years. But if we reduce our emissions drastically, and we've found that we have the technologies to do so, we can curb warming in time scales that are on the scale of our lifetime. So, we're not just talking about for generations to come and our great-grandchildren, but we're talking about having an appreciable difference on reducing warming during our lives.

NNAMDIKate Johnson, how capable is D.C. right now of addressing climate change? What specific steps is the city taking to mitigate the effects of a warming world? And what is Climate Ready D.C.?

JOHNSONSo, Climate Ready D.C. is the District's plan to prepare for climate change. So, we are definitely taking the approach that Jason described of risk management. So, we have an ambitious commitment to make D.C. carbon neutral by 2050. That was a commitment that Mayor Bowser made following the Trump administration's withdrawal from the Paris Climate Agreement.

JOHNSONAnd so we're doing a lot of work to reduce our emissions, and we've actually cut carbon pollution attributed to D.C. by 30 percent since 2006. But we also realize that, you know, no matter how good our offense is, we still need a good defense. And that's really what Climate Ready D.C. is. It's a plan that looks at how we can prepare our residents, our businesses, our built environment for a climate that is warmer, that includes more extreme weather events which can mean things like power outages. So, we have a lot of actions in that plan that sort of address each of those climate risks across a range of different sectors.

NNAMDIHere now is Judith in McLean, Virginia. Judith, you're on the air. Go ahead, please.

JUDITHThank you so much, Kojo. I wish to speak to the problem of economics, as it regards climate impact here in McLean, where we have a booming business world. But we had two thousand-year floods this summer, which completely washed out and shut down roads for months at a time. And the stream that runs by my home has so engorged, that it is no longer a residence that would be allowed, permitted, because of the huge amounts of runoffs from development, but also the funds.

JUDITHAnd I have never seen, or have not been successful in finding out, how does the economic engine that taxes the development industry and the business community correlate with long-term planning with respect to water in my part of the world? That is to say, Fairfax County. I'd love to know, because I can't find out.

NNAMDIThat's a very tough question, and I don't know if any of our panelists has that expertise. The relationship between development, economic planning and climate change. Do you want to give that a shot, Kate Johnson?

JOHNSONSure. I can't speak to Fairfax County, but I can mention a few things that we do here in the District. So, if you're doing new development in D.C., you're subject to a couple different rules, one of which is our stormwater management rules. And so, whenever you're doing large development, disturbing a large lane area, you actually have to make sure that you are managing storm water on your site.

JOHNSONAnd so what we've seen is that as a lot of development in D.C. is actually redevelopment -- since we're a lot more built out than, say, Fairfax County -- that thanks to the policies we have in place, that new development tends to be greener. It tends to manage storm water better, have less pervious surfaces. So, we actually see development as helping us, you know, parcel by parcel, address some of the risks.

NNAMDIIlissa, you used to manage a Twitter account that shared only good news stories about climate change. (laugh) Given everything that's been happening lately, we're desperate for something to be hopeful and happy about. What do you have for us?

OCKOSure. So, I was talking to a colleague a couple days ago exactly about this, about, you know, all the good things that are going on and what're, you know, some of the more exciting things that she's heard of. And she just looked at me and she was, like, there are a million. (laugh) Like, she didn't even know where to begin. And, honestly, I mean, where I work at Environmental NGO, that's trying to work on solutions for climate change, I feel like I'm exposed to so many of these good things that are going on all around the world and all over the country.

OCKOMost recently, the last few weeks, we've had some major commitments by large corporations such as Pepsi and Starbucks and Microsoft and BP and Goldman Sachs, and the largest utility company in Arizona that have pledged to reduce their emissions from greenhouse gases. And so we're seeing all of these large corporations have these commitments. And they're just rolling in, one after the next. So, that's an example of something that's really positive and hopeful.

NNAMDIOnly have about a minute left. Joanna Lewis?

LEWISI would just add that I think, you know, the need to deal with climate change is unleashing innovation around the world. And we've seen the cost of solar panels decline by 94 percent over the last 10 years. You know, this is really exciting, because it means, you know, we're now building more clean energy than we are dirty energy, because it makes economic sense. So, you know, even if you're not worried about climate change, you're probably worried about air pollution. You want good jobs, and I think that we're seeing these industries providing that.

NNAMDIBriefly, Jason Samenow, 2019 capped the hottest decade on record. What does this trajectory tell us?

SAMENOWWe should expect more of the same. And if not, to see some of these impacts accelerate in the future decades. But the good news is, is that if we take the actions that my colleagues here, Ilissa and Joanna, just spoke about, we can slow this down. We can adapt and we can ensure a brighter future.

NNAMDIJason Samenow is weather editor and chief meteorologist for the Washington Post Capital Weather Gang. Joanna Lewis is an associate professor of energy and environment at Georgetown University. She serves as director of the Science Technology and International Affairs Program. Ilissa Ocko is a senior climate scientist for the Environmental Defense Fund. And Kate Johnson is chief of the Green Building and Climate Branch at D.C. Department of Energy and the Environment. Thank you all for joining us.

NNAMDIToday's conversation about the local consequences of climate segment was produced by Julie Depenbrock. Looking ahead, we'd like to invite you to the next Kojo in Your Community conversation about changing immigration policies and their impact on local students and families. It's on February 25th at the Columbia Heights Educational Campus. That's on 16th Street Northwest. Learn how to get tickets and more at kojoshow.org.

NNAMDIComing up tomorrow, on the 100th anniversary of Prohibition, we look back at that failed great experiment. Plus, how should we protect ourselves from the Corona Virus and other contagions? That all starts tomorrow, at noon. Until then, thank you for listening. I'm Kojo Nnamdi.