 What I'd like to do is talk specifically about a frame that I think will help people orient towards solutions, and I'll talk about a few specific elements of the science that are fundamentally different than what just a few years ago was completed, the most recent round of reports from the environmental climate change, where we produced a definitive statement of what we know and did know, but in 2016 what we know and don't know is really different than in 2014 when some very important concept on children and opportunity lay in way for the work that all of you have been doing for the following years. So what I want to do is highlight the eight ways the world has changed since the last five years you were born. The first is that the idea that what we've installed has gone away. The second is that we're finally seeing the beginning of the separation between a very long link between emissions of e-trapping gases and opportunities for economic growth. The third is that we're no longer in an environment where we can say, oh, this single event we can't attribute to climate change or we can't. Now we know a lot about the relationship between single events, the odds of single events, and human cost climate change. A little environment in terms of understanding the relationship between climate changes that have occurred and economic damage is what's the sensitivity of world economy to climate change. We know a tremendous amount of more about the relationship between climate change and sea level rise, and in particular we know that the major ice sheets, Greenland and Antarctica, are up against major instabilities that can lead to commitments to very large marine meters of sea level rise over coming centuries. I wonder about two aspects of the solution space that are also really important. The first concerns will call co-benefits opportunities for not only addressing climate change but stimulating economic growth, those more robust communities, encouraging equity, dealing with poverty in a way that we do really understand even a couple of years ago, talk about how I think the landscape has really changed in terms of whether or not the world community understood that the transition to 100% to non-admitting energy is something we could accomplish. I think the answer only a few years ago was maybe now the answer is clearly yes. And then finally I want to talk about a couple of implications of the 2015 Paris Agreement where other nightfall countries came together and said this is a road for tackling the climate change. So the starting point is that we need to understand the challenge of addressing climate change and the challenge in understanding, managing and reducing risks. It's never going to be about definite impacts that can be avoided and it's never going to be about having 100% certainty about the future. The way we deal with risk is the way we deal with risk and everything in financial markets, in non-climate related natural disasters and in our decisions about highway safety. In 2013 we have sophisticated tools for dealing with it. We've been a conceptual framework for thinking about these issues. We see the risk of climate change impacts is really being embedded in the matrix of three major kind of driving factors. One kind of driving factor is the hazard of the actual physical triggers from the climate system. The second is vulnerability, how susceptible to harm, how prepared are we to deal with the effects that occur. And the third is exposure to what kind of assets are at risk and if you've got a major factory or island complex and you're right at the edge of the complex, it has a different level of exposure than it's just a few hundred units back. There are at least five reasons that it's really important to think about the challenges of climate change, the challenging, managing risks. The first is that risk connects the future with the present when we know we experience big damages from climate related events now. And we can understand how changes in the frequency and intensity of those events will play out in increasing damages in the future. The second is that an emphasis on risk helps with the focus on climate extremes. You can think about extreme conditions as the sharp end of the climate stick. That's where things break. It's where damages occur and it's where we need to be prepared to deal with the kinds of outcomes we encounter. Motivation for the outcome of risk framing helps us understand that we need to be alert to and prepared for the full range of possible outcomes. There's a tendency in lots of kinds of modeling to say, well, what's the most likely answer? And it's the kind we don't really care what the most likely answer is. What we care about is the kind of conditions that might cause severe impacts and about which we ought to be prepared. So just like when a briefing designer says we want to design a bridge for 10 times the maximum load under the heaviest imaginable wind, we want to design a society that can deal with questions if the outcomes are at the bad end of the range of possibilities and not just the most likely answer. Motivation for thinking about risk is that we have a wide range of relatively successful, sophisticated tools for dealing with risk. And these range from insurance policies to financial mechanisms to commitments to national security. Risk is something we know how to handle in society and if we confront the climate challenge with the same kind of risk manager perspective, the views for everything else, we can be successful. Motivation for thinking about climate is a challenging measure. Risk is recognizing that climate changing at the same time lost a lot of things are happening. Land use has changed, human populations have changed. At the level of education, the level of economic aspirations are changing, then all of these things fit together into a complicated matrix where the outcomes for a society may be primarily driven in some cases by the climate trigger, or they may primarily be driven by a population trigger in others, but with climate change acting as an example. We need to recognize that we live in a multi-stress or multi-factor world and then simply say, oh, we're not a hundred percent sure if this impact is caused by climate. We can't use this as a motivation for slow action. The first thing has changed since Paris and the narrative among climate skeptics that are warming hasn't changed since 1998 when we had a huge Elmino year and people can look at the trajectory of global average temperatures from here to about there and say, well, I don't see any warming. But the two fundamental things have changed. One is that there's been a growing appreciation that internal variability is in a huge trajectory. And if you look at the century scale pattern of temperatures, it's weird. There have been some decades where they've found warming and others where they've worn. And it doesn't mean that warming is turning on and turning off. It means that the extra heat that's being captured in your system is showing up in some places and sometimes in the atmosphere, sometimes it's in the ocean another time. What's especially dramatic about this picture, of course, is that the idea that warming stalls has been shown to be fundamentally incorrect by the temperatures in 2014 set a record in 2015, which was dramatically warmer at the global scale than any previous year. Warmer than all previous years by the largest market the first year where the global average temperature was more than one sea above industrial. And then of course 2016 has been warmer still. We just had the 16th consecutive month that set a temperature record, the all-time hottest, I don't see the August number yet, but the all-time hottest July, which followed the all-time hottest June, which followed the all-time hottest May. The first three months of this year were already more than 1.5 seas above the pre- industrial levels. That's an important number because 1.5 now is the new aspirational target to be considered in the Paris agreement. And we're already within a whisker of reaching that. Not to say that we're committed to that level of warming for every year in the future. There still can be a lot of important variables, but the situation is really changing. And it's even more impressive that the whole idea of a hiatus never really had an attraction. This is a result of a really nice work by the National Privatic Data Center, part of NOAA, but Stanford groups have also done a beautiful job of demonstrating that there was never a hiatus. The area of temperature from 1998 to 2012 basically was a part of the historical revolution of climate. What this figure shows is that if you do an accurate representation of the temperature during this period, the average warm was a tiny bit less than the average warming during the base period. But then if you actually look at the period from 1998 to 2014 and compare it with the second half of the 20th century, the best revision of the numbers is in the square symbols. It seems that the rate of warming during this hiatus period was, in fact, exactly the same as during the second half of the 20th century. There simply is no evidence that there was ever any slowdown in continuous dumping. Some years it shows up in much warmer atmospheres. In some years it doesn't, but it's still there in influence. From the IPCC was the growth rate from 2000 to 2010 was substantially faster than it had been in previous decades. A main consequence of rapid in India, but we've seen an incredibly interesting thing happen in the last couple of years, and that's shown here in view of work from Rob Jackson and from 2013 to 2014, the year was relatively rapid, well, we got a growth. But emissions only increased by 0.6%. In 2015 was another year of, but there was as far as we can tell the decrease in CO2 emissions from possible. And so for the first time we're seeing a separation between what happened in centuries, scale, or CO2 emissions. But then we're finally seeing this break, and we're seeing it break as a consequence of differences in the way income is generated and also more and more of the energy production, a switching to lower emitting technologies. And I'll come back to this later. But it's a fundamental difference that we, in the last few years, we could begin to see the separation. So that's the same. In the ground world, we are no longer, say, climate change is a hypothetical piece that have already occurred, impacts of climate change from the equator to the poles and from the coast to the mountains. In the most recent ICC report, we produced a map of the kinds of impacts that have occurred in the places that they've been observed in developed countries, in the developing country, physical systems, things like the behaviors, glaciers, and flow of rivers, in biological systems, abundance of wildfires, the ranges of plants and animals, seasonal activities, and in human systems, things like food production, the abundance and frequency of conflict, parts of the Earth system. And an accident we would make, an accident have already been to the climate changes have already occurred, including changes in snow and ice, changes in river flows, changes in wildfires, changes in the distribution of abundance of plants and animals, and changes in activity. And we're seeing this is from Greg Adler's work at Carnegie, who's also a part of the Earth system science department, and based on a comprehensive airborne survey of California's forests, how many of California's trees are water stressed as a consequence of profound browser began in 2011, we're still in now. And this is a map of the water content of the state's forests, and the redder colors are less water, more drought stress, and this indicates severe drought stress for something like 60 million trees. So we now know that this drought, in which we can clearly identify as being more likely as a country, is having real impacts for playing out, not only in the death of trees, but also wildfires, insect outbreaks, and a wide range of secondary consequences. And to this point, we're seeing the vulnerability and susceptibility to us. Who is it that's susceptible, and why? And we've attended historically to think about vulnerability that impacts Sudan, and there are certainly lots of reasons that poor people are especially susceptible to impacts of climate change, and that includes, you know, weak governance or institutions of limited financial resources, but what's striking is when you look around the world and ask where the damage is as a consequence of inflated events are occurring now, they're not just happening in a little bit more areas. In fact, rich areas are by far suffering the highest economic damage. This is a picture of New York City while we're currently standing in 2012, a region that experienced $60 billion of economic damages as a consequence of something that had been degraded from a category one, such a future risk. And the way that the IQCC characterized it is the more warming occurs and the more we face a risk of impacts that are severe. There is, is not, not one of a depressing message, but it's one that if we can limit the climate change to the lowest amount possible, even above the pre-industrial, we can avoid it, and it concerns this topic of single event attribution. Just a few years ago, the internet was, well, we expect an increase in various kinds of extremes from climate change in a single event to climate change, but as a result of some old statistical work done, so a different law school here has contributed a lot to this. We now can assess for single events how much the climate changes that have already occurred have altered the odds of an event like that. So for something like 80 events that have been analyzed in detail, those that are related to heat waves or extreme hot spells, we've seen that something like 95% have a climate change signal. A good example is the European heat wave of 2003, which led to many tens of thousands of deaths. We know that the probability of an event like that was at least double as a consequence of the warming that's already occurred. If we look ahead at participation events, about half of those show a climate change signal. And while we go farther and farther away from warming the extent to which the attribution detects a climate change signal goes down so for droughts, it's about a quarter for things like wildfires, a few single wildfire events, or the wildfire season in California 2000. One of the interesting features of this single event attribution was that increasing in an environment now where people can, and it leaves it, it really sets up a very good way of climate change and economic damages. And for this series of climate events resulted in a change in economic output. And a really creative approach. Countries shape out in terms of global economic growth, their national-scale economic growth is a warmer period. And recognizing that when we see most of the climate impacts unfold they unfold in a nonlinear way. So that when conditions are cool, the warming may actually produce benefits in the high-emission or hot warming may produce damages or other kinds of challenges. And that's exactly what areas that are cool, cool in about 14 C on average, is better, areas that are hot, warmer in about 14 C, 14 C is the annual average temperature. The sensitivity of the damage they would courted from this national-scale macroeconomic data that they found is a continued high-emission global growth is something like 23% within 2100 and we would have expected in the absence of climate changes on global economic activity. What's even greater concern is that the distribution is still unequal. So you can see that the range of estimates for Europe across the bottom is continued economic growth as a consequence of the warming action that's in the face. Severe economic consequences with a change in per capita GDP on the order of 75% or even more is a consequence of continuation on a world of high emissions. What we really see is that the countries that suffer the biggest impact on economic growth, a wide range of sources in order to generate economic growth will move to the airpopulation.com and turn to sea ice. The solid material flows across complicated landscapes. It has to do with how stable these large ice cliffs are. It has to do with the consequences of changing the conditions and the interface between the ice and the rock as a consequence of meltwater. So historically when we talked about sea level rise, we mostly talked about thermal expansion as the main contributor and this amount of sea levels will lock up in the world's ice sheets on land. About seven meters of sea level will go up to 26 feet on the Greenwood Ice Sheet and right around 60 meters around 100 feet of sea level equivalent on the Antarctic Ice Sheet and one of the things that there is a paper, just in the last few months is the mechanisms by which especially the Antarctic Ice Sheet where much of the ice is called grounded. It's sitting on below sea level. It's susceptible to rapid conversion to liquid water. It has to do with the stability of these large ice cliffs. Basically you get an ice cliff that's taller than about 100 meters sticking out of the water and the ice isn't strong enough to support itself and it gets to collapse as a consequence of gravity. We know this new recognition of the sensitivity of the instability of the ice cliffs into the model. There was a new range of commemutions to sea level rise or Antarctica. We've continued high emissions. The red line there we're looking at 2100 is recommended to sea level rise. On the order of an extra meter, it's on top of the thermal expansion, the commemutions from glaciers and the commemutions from Greenwood that are driving the bulk of the sea level rise to date. What's most concerning especially for people in low island nations is that if you assume these results out to 100, the commitment doesn't 16 years of sea level rise by 2100. That's a change rule that becomes an existential issue which is not a question of how am I going to reshape my economy and simply gone and the only possible is to find somewhere else to live. So I think this recognition of the very large potential for long term, one of the motivations of the ambitious temperature targets including targets below 2C. And here you can see the implications of stabilizing climate at 2C or better looking at on the border of almost 16 years. I should say that over the last few decades it's grown and even though that's beginning to change, it's not sure if you step back on this. And it has to do with how to what we really need to do is we really need to do the solid climate problem down to zero. If we want to stabilize it 2C, we need to find a way. Something that uses the remaining budget is the current nations. Here's another way to think about it. This is based on the specific simulations of the peace report. Continue to have a suit of concentration to about 1000 BPM suits equivalent to 2100. Currently the suit of concentration BPM of CO2 equivalent of 400. Stabilizing warming at 3C or 2C of the striking feature of these trajectories is that they reach zero. And in fact this 2C trajectory actually tends to go below zero. Talk about mechanisms that might use for actually removing carbon dioxide in the long term. The 3C trajectory hasn't quite reached zero when I was a guy who reached zero eventually. And even higher amounts of warming eventually through all of this is that when we talk about solving the climate problem all of it with ambitious mitigation and something like 2C, less ambitious than 3C or we go through the 21st century accepting very high levels of damage and less stabilization for enforcing. We still eventually so this isn't a question of whether or not we will solve it. It's a real good question. It's a couple of minutes talking about what we might think of as the solution space for the climate problem. And it's got investments in the audience. The first thing to know when we think about designing a solution is that there aren't no as well as commitment to coping as well as we can that the climate change can't be avoided. It's really building momentum and we're learning more and more about what came and can't be done in adaptation. The striking thing we know about adaptation is some damages and the more the climate change, the more we won't be able to adapt. This week you'll hear a lot about it in your careers. It's effort to be able to get investments in moving us away from greenhouse gas and that I get an in on is that we used to see essentially three buckets of alternatives that were competing with each other. One was investments in economic development. The second was investments in mitigation, increasing mass climate change which occurs. And the third was investments in adaptation. Now increasingly we see that there are a wide series of multiple wins on the bottom line and you can also yield benefits in adaptation. And also you can benefit from $100 for about $50,000. It's a stressful and many relationships. We were all here to break this relationship. At the same time we're driving emissions to act. So that's really country emissions in the most recent years from the US and the European Union. Think about where emission growth needs to be tackled for the developing world. But we also need to recognize on a per person basis emissions are still high in the developed world. You can see that here where this is per capita emissions now. Six tons of CO2 equivalent per person per year. The US is still about three times that level substantially above it. But one striking thing about the pattern of per capita emissions is it varies dramatically around the country and there are lots of lessons in this state by state. I'll title up in my opening with you guys. It's no great claim to pride but in California we do have a lot of claims to pride where our emissions are only about half US average and they're typical of per capita and they spend as much energy on heating and cooling as in other parts of the world. But part of this in California really has been a leader in the implementation of climate solutions and has been everything from care quality standards to building efficiency and we learned in many ways California is a laboratory for ambitious investments in solving the climate problem and it makes it a great place to think about and try new things. Thoughts here are on that we're trying to address and this is the combination of different energy sources in US electricity generation 15 and you can see there's about two thirds of coal gas and oil as a result of increased availability and lower prices through hydraulic fractures. What you need to do is eventually figure out how to overwave and even though the assets of per unit of electricity delivered about twice as efficient in future different stages that future emissions from gas can cause about as much cost. And we know how to do that and we know that when it's all increased amazingly rapidly from 2006 to 2015 we saw 52 times the increase in the deployment of some of the 7 fold increase in wind in US electricity but there's still a tiny tiny fraction and there's a lot that still needs to be understood about how to deliver as everyone's already begun to describe and many of you will think about the amounts of these renewable and what we do about storage and distribution which is about the feasibility of doing that. So here are current and projected prices for different electricity sources cold. And the striking thing we're looking at in the future is that if we look at the solar PV at least the low end of the ranges for low wise console electricity are cheaper than the low end of the range for an environment where at least in principle the renewables are cost competitive may even be cheaper if we can figure out how to build an energy system that can accommodate very large amounts. Increasingly it's clear that realm of possibilities basic problem which is that there's a vast amount of convenience in the availability of electricity in solar all these cities. They said let's make some really heroic assumptions about load shifting and about storage and everything we could think of that would allow us to build an energy system that could accommodate vast amounts of renewables and we match supply and demand as you can see in the top figure it's a good proof show that with really ambitious low balance components it looks like it's technically feasible to build an energy system entirely on renewables that we probably don't want to probably be too expensive and an energy system that's got fossil with CCAS that has some nuclear is likely to be a lot more robust and cheaper and more reliable. The sixth way the world has changed since the last time is for co-benefits. Opportunities for co-benefits in terms of jobs. Everybody's seen the statistics that we've seen dramatically more new jobs in solar than we've seen jobs lost in coal. Seven million people a year died as a result of air pollution. The premature mortality in the U.S. is the result of particulates from coal. We know that potentially use those renewable resources as an engine for development in a way that wouldn't be possible at all. It would be hard about incorporating new energy technology into a society that's focused on seeing lots of ways of commitment to 21st century energy systems. And the eighth way is that two biggest challenges with a stable policy environment in which moving forward that their investments are going to continue for long. So with Paris we got a universal binding agreement where government contributions and they range from airy ambitions to peace commitments of peak ambitions by 2030. For ones that are still getting their act together with many developing countries that are really talking about commitments to finance and technology and then really the high environment on Stanford is an increasing recognition of the role of non-state actors where what we really wanted to address is the fairness issue. It addresses the policy continuity issue every country. That's why I want to stop. This is a problem we know we need to solve. It's a problem we know we need to solve and it's a problem that all of you who are undertaking will be able to celebrate your commitment working with all of us to solve this problem to be happy to take any questions. It was whether renewals when the solar has zero suits will be able to melt the silicon crystals and grow them and so there's a huge amount of input that's required. That's where it comes from for making the PVs important. What powers the trucks to take the PV out to where the PV is important. The system works but as we get more and more of the system based on our rules so that eventually we can do it there and we don't really have the vision at least the need for liquid fuels from biomass which are potentially zero or any. But we may eventually need to have ways of where we're moving from the air in order to offset the same emissions. What I've asked from is that if we're involved in this we ought to think about our lifestyle and what are the intermissions that are associated with what I do, especially what we've got coming up and our vest style and I think it is really important to discourage another super important but for me personally it's hard to imagine the kind of rapidity of the transition we need without having a system to have a harder solution rather than just to see that they want to be a part of the solution. I say that campus energy is a really key part of this and I hope some of you are interested in understanding and contributing to the zero emissions profile the new central energy facility do people see that as a super compelling increase in the overall efficiency and the ability of the university to use a separate new energy is a really big think about investment you need to recognize that right now we have an energy system we saw that grass about two thirds based on fossil energy sources and if we were to shut that off tomorrow, which is in some way sort of both for investment would be the economic activity around the world, grinding through the media we would basically be eliminating the legitimate we need to figure out a way to gradually transition in a way that could be a part of the solution and for me that real question is how to both rapidly rather than ways