 Great. It is absolutely wonderful to talk with all of you today. And I think what you'll find through this week is that Stanford is an amazing place to study climate and energy, and I'd argue that that is particularly because it is so focused on creating solutions. So I'm going to run with a theme that Sally introduced a lot, and it's about the connections. The reason why climate and energy is riveting is because those topics intersect with almost anything we care about. They are central to a good quality of life. That means that there are different ways you can be unfolding these issues, whether you're thinking about engineering or the private sector or law or even music. And the three examples I use are going to pull together different threads across the climate challenge. I'll talk as Sally introduced about global scale assessment of risk, what's at stake in a changing climate, and how our knowledge of those risks really underpins the goal in the Paris Agreement of limiting warming well below 2 degrees Celsius. I'll talk a little bit about the broad interconnections of how we solve this challenge at the global scale. What does it mean to put together the different pieces of land and energy transformations that need to happen. And then I'll also tie in at the end how people are dealing with the impacts of climate change on the front lines. I'll use flood risk and flood risk management as an example, but here in California, many of the exact same themes apply in the space of fire. So where are we in the climate challenge year 2018, recognizing that that basic understanding went all the way back to the 1820s. So here we have at this point a vast body of evidence. It is unambiguous that the climate changes that have already happened have had widespread impacts on every single continent, from the tropics to the poles, the mountains to the seas. If there's a single way that our understanding of the risks unfolding in real time has changed powerfully over the last decade, is that that scientific understanding can now tease out the role of our heat trapping emissions event by event. So they're already, last time I checked, five papers published on Hurricane Harvey in all the different ways our emissions of heat trapping gases made that event more powerful, more intense in the flooding that occurred. Same deal goes for wildfire. We have increased wildfire risk across the American West due to hotter temperatures and reduced precipitation during the summers. But it's not just doom and gloom. We really increasingly see responses unfolding no matter where you look. I will talk today a lot about the adaptation dimensions, how communities, economies, societies are preparing for the risks. It's easy to show a picture of hard infrastructure, but what I will argue is that it's actually how the hard infrastructure interfaces with the soft infrastructure, basically the fact that communities have to come together. It's about early warning, land use planning, and the like. And for most of the rest of the week, you will be hearing all about the different innovations happening in the engineering dimensions, the finance dimensions, the policy dimensions of our energy transition. A theme that's going to run like a heartbeat through this presentation is the fact that increasingly it's recognized that viewing the climate challenge as one of risk is an incredibly powerful entry point. Responding to climate change is a challenge in understanding, managing, and reducing risks. So what do I mean by that? Risk is the potential for consequences, where something of value is at stake and the outcome is uncertain. Key thing, though, is that risk in a change in climate is not just about the climate. The hazards, the sharp end of the climate system, whether it's a heat wave or a drought or a flood. To create damages that matter, it's really how those hazards intersect with societies. What assets or economies or communities are exposed and are they susceptible to harm? So this focus on risk, where you can think about it as the probability of hazards happening times the consequences that would occur, it's a really compelling way to connect problem to solution. A, it really emphasizes that these interactions between climate and society are pivotally important. It also connects the climate challenge to the fact that we already deal with weather and climate variability and energy in all those dimensions. And the real question moving forward is how some of the odds change and how we can address them proactively. The climate challenge as a risk challenge is also a powerful entry point because we need to attend to the extremes, the low probability outcomes that might carry high consequences. Sally referred to the potential collapse of the West Antarctic and the very large amount of sea level rise that would be entailed. Also, anything that we do as people is about risk. The future is always uncertain. And basically saying that climate change is no different from any other decision-making context means that we can pull on the same tools from engineering or law or business to address evaluation of what the risks are and how we can respond. Okay, so what I'll do is emphasize a few different bodies of research and assessment that have been happening here at Stanford over nearly the last decade. And all of them are going to be about the interconnections, the biophysical and the social and the fact that decisions are happening in real time and we need to make our climate and energy policies effective. Example number one is going to be global scale assessment of what's at stake in a changing climate. So as Sally mentioned, the last intergovernmental panel on climate change assessment of impacts, adaptation and vulnerability was led out of Stanford in the direction of co-chair Chris Field and he worked in partnership with Vicente Barros from Argentina. I was one of the staff scientists directing science making this report happen. So who's heard of dangerous anthropogenic interference? Nobody, one person, I'm not surprised. Okay, so dangerous anthropogenic interference is otherwise known as dangerous climate change and governments around the world for nearly three decades now have come together with a goal of avoiding dangerous climate change. And that meant that our mandate for the intergovernmental panel on climate change over 300 experts from around the world was to figure out what do we know about dangerous climate change? Is it happening right now? Will it happen a decade from now? How about in year 2100? There is a lot of science available on the impacts of a changing climate and in particular we had 14,000 that were cited in this report. And the goal was to say, okay, evaluate what's at stake and in particular, package it in a way that we can see the risks overall and that all of the decision makers thinking about what our long-term temperature goal should be, what is safety in a changing climate have something to work from. And the approach we took to move from a vast body of evidence into a coherent picture that could inform global goal setting was two different approaches that I'll describe. Key risks and reasons for concern. So key risks applied across every sector whether it's water, land, energy, biodiversity, urban areas, rural areas. And the goal was to highlight across all of those different contexts and then on every single continent what is most deserving of society's attention. And the really cool thing is that we weren't typical scientists. So if we were typical scientists, we would say I'm only gonna tell you the answer if I can definitely prove it. It's called type one error bias. Instead we recognize that if you're doing a global assessment you have an order of magnitude more literature available for Europe than for Africa, even though arguably the impacts may be unfolding in much more profound ways already across those against the grain of evidence. And you really wanna come up with criterias that are geared towards what is most important and not just stuck on the things that we absolutely can prove for certain but are attentive to low probability, high consequence outcomes. So the different criteria applied were how big is the magnitude for food and water security or extreme events unfolding around the globe? Is there irreversibility, for example, extinction or the collapse of an ice sheet? How do we understand the potential to reduce those risks? So this key risk approach interface with the primary scientific literature to identify for every single sector and every single region across the human experience, what risks are most deserving of society's attention, how the risk levels jump up through time and the gray here, how much we have potential to reduce them through adaptive actions. And what was really neat was that there are huge commonalities across regions, even though distinct issues come to the fore. Those huge commonalities are the risks associated with food and water insecurity, the risk from extreme events and also the risk for biodiversity and nature. We then took those 142 key risks and packaged them together into an assessment of global scale risk and a change in climate. So this is like the figure Sally depicted, except it's one that we published afterwards where we have popped up the lid on the reasons for concern or the burning embers or, I guess, the flame diagram. And we are showing here how each of those different key risks interface with broad categories of global scale risk. So the key risks are these little icons informing judgments about when impacts go from in yellow detectable through to in purple, impacts where there is very limited ability to adapt in real time. And there are five reasons for concern here because values matter. There is no one way to measure what's at stake in the change in climate. Different people will put different emphasis on the present versus the future or the rich versus the poor or outcomes that just affect nature and biodiversity as compared to entire economies. But what we see is across five very different definitions of risk, they climb with continued high emissions of heat trapping gases and at levels that could be reached in this century, it doesn't really matter how you define the risks, we're looking at the potential for severe pervasive irreversible impacts at the global scale. And these different dimensions of Sally described range for the unique and threatened systems on the front line in a changing climate, whether that is coral reefs, Arctic sea ice systems or small islands facing substantial inundation. They stretch through to the unfairness factor in a changing climate, the basic idea that when anything happens there will be winners and losers and this one in particular is about those who are most affected. And then there are the large scale singular events, the tipping points, the types of events where it is very hard to say exactly when the West Antarctic will collapse or exactly when we'll see a threshold in terms of loss of Greenland or then the East Antarctic in turn. But we know those are phenomenally consequential events that will lead to meters of sea level rise that will be exceedingly difficult to reverse. The last thing that Sally mentioned about this figure was that we took it into decision making contexts. So for the very first time in the long history of international negotiations on climate, there's something called a structured expert dialogue. And it was outside of the formal intergovernmental panel on climate change contexts. So it meant that we weren't battling with the decision makers on exactly what word to describe severe pervasive and irreversible, but instead we were just answering their questions. And what was remarkable was the way the different countries interface with all of the evidence underpinning this figure. So St. Lucia, Barbados, Kiribati, would point to one of these embers, which one do you think they might point to? I think I heard the answer there. So small island nations were really concerned with the communities that are most effective that have contributed least to the problem of a change in climate, but may experience some of the first impacts or are already experiencing some of the first impacts. And essentially they were interested in the evidence basis here. Saudi Arabia had a different perspective and theirs was, for example, that we're missing an ember. We don't have an ember for risks to fossil fuel exporting nations. That is a very valid value-based perspective that has to be grappled with on our energy transitions. These have to be just and fair and negotiated both through how the private sector evolves and our public policymaking. And then Europe usually was in between those two extremes trying to negotiate a path forward. So this in many ways was the evidence basis that informed the long-term temperature goal, limiting warming well below two degrees Celsius, pursuing 1.5. And come back to this risk diagram now. So in some ways that is one glimpse of global scale assessment of risk in a change in climate. And what I'll now turn to is how that assessment of risk interfaces with some of the broad notions of what it takes to get there at the global scale. Okay, so this is gonna be a different entry point on a lot of the same territory that Sally introduced. As Sally emphasized, when we put CO2 or other long-lived climate forces into the atmosphere, it is fundamentally different than many of the traditional air pollutants. It is fundamentally different because the consequences of that, the warming that is realized is nearly permanent. Some of you are physicists, physicists in training. Okay, this emerges from, there we go, we got one. Some of this emerges really from the physics of how the climate system works. The basic idea is that when CO2 is in the atmosphere through time, the ocean has become less able to take up heat as they warm through time. So even though it will drop in concentration, that warming is nearly permanent. So what that means is that we've got that linear relationship between our cumulative emissions of heat trapping gases and the warming that results. Pick a limit that you want to set on temperature like two degrees Celsius and you have a finite budget. So then the income applied policy analysis. What does it take to get there? So this schematic here shows a very simplistic summary of a vast number of model runs from integrated assessment models that are trying to figure out at the global scale, how do we get there? How do we limit warming to two degrees Celsius? So here we see our emissions historically in gray. This black line is across many different runs that limit warming to two degrees Celsius in year 2100. These types of model results carry huge real-time relevance. This black line here essentially carves out article four in the Paris Agreement, the goal of peaking emissions as soon as possible and driving them to a balance between sources and sinks in the second half of the 21st century. So when you look carefully at these data though, something really fascinating emerges. So this black line is normally what's reported, the trajectory of net emissions from these different scenarios that limit warming to two degrees Celsius. But then if you ask them and interrogate them a little bit further, what you find from these model-based results is that they usually have gross emissions and then gross negative emissions. This deployment of negative emissions technologies is in many of these model-based scenarios over 15 billion tons of CO2 removal per year at the end of the century. If you remember the numbers Sally showed from the global carbon project, that is well over a quarter of our current emissions into the atmosphere. So these types of deployments of negative emissions technologies, let's just say have caused a lot of angst. We recognize that there can be approaches for removing CO2 out of the atmosphere, but they're really important questions of the degree to which we want to create something that is more of a land sector problem in addition to the energy sector transition that already has to happen. So when I say negative emissions technologies or approaches for removing carbon dioxide from the atmosphere, they can take a few different flavors. They can be things like forest and soil stewardship, how we manage our lands, whether we grow trees or log intensively, can very strongly correlate with how much carbon is on the landscape. There are also approaches called bioenergy with carbon capture and storage actually refers to a bundle of different technologies that can be used to both generate electricity and store CO2 underground. There's also direct air capture. Later today, we're gonna talk a lot about BEX on a panel. So I'm just gonna introduce some of the framework we use for analysis in this space because I'll argue that's the same type of approach that works really well to think about many different features of the climate challenge. So in essence, this is our analytical approach. It's easy in a broad scale sense to think about what carbon dioxide removal might look like in our portfolios of responses, but we recognize that there are some biophysical limits. How much land are we gonna use to grow bioenergy crops? There are techno economic constraints. Are the technologies commercially ready? Are they profitable at present? That question about profitability also ties to what the policy and finance environment looks like. And then you've also got social constraints. Nimbism, for example. So the next three slides, I'm just gonna briefly refer to work that we're gonna unfold in great length this afternoon. And then I will also introduce how we've been driving forward some of these themes also in particular in the California context. So number one, we looked at the biophysical side and how it interacts with all of those other social, techno economic and institutional constraints. Asking, what does it take to get to 15 billion tons of CO2 removal per year in those model runs? And what we found is that the energy crop expansions over the next three decades are far outside the rates of land use transformation that have been realized historically. For example, with soybean, the fastest expanding commodity crop to date. And for some of the runs where they aren't quite so wildly fast in terms of land use transformation that's occurring, there are massive pulses of reforestation. So these types of results really suggest that you probably don't wanna look at 15 billion tons of CO2 removal on the face of it and think that it will easily materialize. In work that we'll really unfold this afternoon on what I'll just emphasize here is that we've taken some of those constraints and used them as an entry point for looking at near term opportunities. E.J. Beck, Energy Resources Engineering advised by Sally Benson, for example, has looked at places in the U.S. where you could do becks without pipelines or without long distance transport of CO2. This adds up to about 100 million tons per year. We've similarly asked this question where we say, great, we're gonna freeze this at current institutions, current policies, current infrastructure, bioethanol refineries, current technologies that are commercially ready right now. And there are opportunities for becks that can be deployed at existing bioethanol refineries as we'll describe in depth this afternoon, even though they are more like 0.1% of the deployments that you see in the integrated assessment models. I'll now turn to the California context. As I hope you will get a good feel for this week, there is the usual California exceptionalism in the climate challenge as well. There's incredibly ambitious policy landscape unfolding in real time. And California also has been a leader in bringing land into the climate policy landscape. So for example, Krista Anderson, a student here, we've worked together to evaluate California's forest offset program. The degree to which land has been used to achieve carbon dioxide removal, it's small, five million tons per year. But a really interesting finding here was the degree to which this involvement of the land sector has reversed the conservation paradigm. So timber companies are participating in this, investment landowners, not because they care about biodiversity conservation, but because there is pricing of carbon that's relevant and they're achieving all sorts of benefits for water quality, biodiversity conservation, recreation as a result. Another theme that plays out really strongly in the California context is that of environmental justice. Environmental justice is actually written into the US Environment Protection Agency as well, really strongly, although you might not guess it from recent actions. It is also here on the books legally in the California context. So our climate policy in California cannot exacerbate inequities related to water, air and other environmental burdens, especially those experienced by the most disadvantaged, most sensitive communities in the state. So for example, California uses a screening tool to look at communities that are already suffering from very bad water and air quality burdens and that have particularly sensitive populations or low socioeconomic capacity to deal with it. And there's been a lot of questions of, well, when it comes to things like forest offsets or the cap and trade program overall, how are these types of policies affecting the most advantaged versus the most disadvantaged communities? Are they creating winners and losers and exacerbating existing inequalities or is it helping ameliorate that? And what we really found in this set of analyses is that it's a good thing that California climate policy is not exacerbating inequities around air pollution in these communities. But the really key counterpart to that is that climate policies are nowhere near what is needed to grapple with air pollution issues in the state. Okay, the last example that I'll work through ties really to hazards unfolding in real time now. I'm gonna work with flooding, but these same themes apply almost equally well in the space of wildfire, drought or other impacts unfolding whether you're looking at communities in California across the US or the globe as a whole. I'm gonna tie this look at hazards in the flood risk space to what's happening and what may need to happen into the future related to adaptation or how we prepare for the impacts. Okay, so when you think of coastal flooding, what you might imagine is something like typhoon, Jebi striking Japan last week. Anyone see pictures of that? Yep, so imagine enormous swells, crashing waves, driving water into communities and radically reshaping what's on the landscape. That's normally what comes to mind when we think about coastal flooding. But increasingly, this landscape of coastal flooding is quite different. It's creeping up on the high tides. There are amazing images of parking garages in Miami Beach where octopus are coming up through the storm drains. In terms of what happens, the pandemonium, when you have this high tide flooding, there are social media clips all the time now of people pushing cars in their bathing suits in Florida as they're trying to wade through the water and get out of the salt that is corroding the infrastructure. So most of the analysis of this high tide flooding, we've got it here in the Bay Area. If any of you like to bike over the Dunbarton, you can see the flooded parking lot right below. It's also happening in the North Bay. But most of the valuations of this flooding that is creeping into our daily life has simply focused on the tide gauges. Where is that water level? And the reason why it is mostly just focused on the tide gauges is compared to the actual impacts for people who are trying to avoid the salt water or changing their commute routes or no longer going to the stores there is because this is really hard flooding to study. These are short duration floods. They last for just an hour or two at a time and data sets are sparse. So what I'll describe here is one analysis led by Miyuki Hino and Samantha Tiver Bellanger. And what's kind of cool here is that Miyuki's a PhD student, but Samantha was at the business school just finished and she also did a master's in environment and resources. It was incredibly cool for me as a PhD scientist to work with a business school student. She had obviously astute attention to profits and business and what the customer experience would be, but she also really knew how to get data sets. The hardest thing here for studying this flooding was figuring out how we could actually empirically validate and test what's going on. So when the parking lot technician would say, no way can you have my data sets, Samantha would call the CEO and there we went. So we just got this paper back from review and the major point from the reviewer is that applied econometrics is impossible to understand in all of its technical details. So I'm not going to do the technical details. I'm just going to say this is a very well causally identified statistical analysis of the consequences of this flooding. And what you see is that as you go from just a little puddle in the parking lot to the parking lot fully flooded, people are no longer visiting. Rain has an independent effect. If it's a rainy day, people don't go out. And this effect of nuisance flooding is lagging through time persisting long after the water has sunk back down the drain. And if you say, well, what is happening in this historic downtown of Maryland, one of the places where nuisance flooding is now a regular occurrence. So far it's about a 2% reduction in visits to the historic downtown. If you extrapolate this out for another foot of sea level rise, what could happen over the next few decades, that's about a 25% reduction. These are obviously things that increasingly we are going to have to grapple with. The last example that I'll give is looking at the full spectrum of how we manage flood risk and a change in climate. The traditional options fall into three different categories. Number one, protection, armoring the shoreline. This is, does anyone know what this is? Clearly study energy in this room. This is the 10s barrier. It is an iconic example of infrastructure and a change in climate. And that is the first piece of infrastructure in the world that has a plan through 2100 and how it will be adapted to the different amounts of sea level rise that can occur over that time frame. And is the first infrastructure adaptation plan that is attentive to the fact that we don't know when the West Antarctic is going to collapse or how fast. So protection is great. It's also expensive. There are limits. And it also often creates winners and losers, those you protect and those at the sides who experience increased flooding. So another common category of adaptation is accommodation. The basic idea that you can change the codes for buildings. You can require the outlets to be along the ceiling as compared to along the floor. The classic line for accommodation is that it has its limits. And I think these houses on stilts are a wonderful example of that. By the way, this is how you adapt in the national flood insurance context at present. So what we've been doing is looking at the third understudied but maybe very, very important at some point along the line, leg of the tripod for flood risk management. We've been looking at retreat. The basic idea that it can be incredibly cost effective, a phenomenal way to keep people safe to simply remove infrastructure out of a flood plain here. This also applies to wildfire. In both the case of flooding and fire, we are incredibly good into moving into the path of harm. So what we've done, for example, is looked at every single instance of managed retreat to date, 27 projects globally that have moved 1.3 million people. What we've really unfolded is that when it comes to managed retreat, you can't get around the fact that there's almost always a negotiation between residents on the ground and an implementing entity, usually a government body. In some cases, residents really want to move. In other cases, they do not. It's their homeland. And then in some cases, the governments aren't necessarily incentivized to participate because the benefits are realized only by the small number of people affected, whereas in other cases, there are broad benefits to society. So the experiences to date, for example, include the Dutch, always very, very good, A++ in the flood risk management space, where they have essentially implemented retreat as a broad portfolio of flood risk management. And in particular, they move people who weren't themselves at risk, but by restoring a flood plain upstream, you could create much greater protection for everyone downstream. Being the Dutch, they had a very strong process of community engagement and they went door by door and allowed people to join this program with quite happy outcomes, all things considered. At the other side of the spectrum, there are some powerful examples in the current world, whether it's indigenous villages in Alaska who are living in these horrifically exposed locations because the US government mandated their settlement locations, been trying to relocate in some cases for decades now, still without success. So across this landscape is very rich, and I'll just point to one more example here, mutual agreement, where we essentially have been saying, voluntary property buyouts are an important way to implement managed retreat. And what I mean by a voluntary property buyout is that most often in the aftermath of disaster, there can be negotiations where a county, for example, using FEMA funds buys out a homeowner, then restoring that land to open space, reducing risk. In the space of managed retreat is a high data context in that there are 40,000 of these property buyouts that have happened in the US to date since 1989. And the kind of fun thing about this study is that the classic wisdom for managed retreat is that it's gonna be poor areas and rural areas that do retreat because they will not be able to afford protection. But what we've really found instead is that it's the rich urban areas that have done this so far, raising some interesting questions around how we effectively and equitably reduce flood risk moving into the future. Okay, last thing I'll say, I don't get this question on campus a lot, but the moment I step off of campus, whether I'm talking to my in-laws or going to a cocktail party is, isn't it super depressing to study the climate challenge? And I will admit there are moments, but really I think it is powerful in that a salad-described climate and energy interconnect with absolutely everything that we care about, and that goes for basically every person in the world. It's really a powerful way to think about building a better world. There are tons of co-authors on all those papers I cited, and I think them.