cc  >> Dan Vimont and I  thank Dick for his very  interesting talk,  and now Dan will be next.  Dan Vimont has been an assistant  professor in the Department of  Atmospheric and Oceanic Sciences  at the University of Wisconsin  Madison since July of 2003.  He's also affiliated with the  Center for Climatic Research  at UW Madison.  Dan received his PhD in 2002  from the Department of  Atmospheric Sciences at the  University of Washington in  Seattle.  His interests mainly focus on  climate variability involving  oceanic and atmospheric  processes including El Niño,  hurricanes, climate change,  atmospheric circulation patterns  and statistical analyses.  Dan is a Science Council member  for the newly formed Wisconsin  Initiative on Climate Change  Impacts or WICCI, and he has  played a critical role in its  development.  Thank you.  >> Thanks, Mike.  >> Thanks, Dan.  >> All right thanks everyone for  coming. 

 I think Dick had a very nice  presentation outlining some  potential impacts of climate  change in Wisconsin and really a  whole slough of impacts that  really impact a number of  sectors in our state.  Today I'm going to talk about  the climate side of things.  Climate change in Wisconsin.  So approaching what we, or  trying to describe a little bit  of what we expect might occur  from the climate end of things  and one of the points that I  want to emphasize here is that  there's, in general, a gap  between what the climate  scientists can say and what  actually means something to  someone.  So what is a two to six degree  change in temperature really  mean.  And this is where WICCI really  is essential because it brings  climate scientists together with  scientists who are studying  impacts.  And it's that ability to bring  scientists together that allows  the assessment of climate  impacts to occur.  And allows us to really explore  adaptation.  So I want to, at the offset,  acknowledge a number of  collaborators in this work and,  as well as, in this  presentation.  Steve Everest, Dave Lorenz, Mike  Notaro at Center for Climatic  Research, Chris Kucharik at the  Center for Sustainability and  the Global Environment, Jack  Williams at the University of  the Wisconsin geography  department, the Wisconsin State  Climatology Office and the  Wisconsin Initiative on Climate  Change Impacts. 

 There's a number of scientists  through WICCI that have also  contributed, excellent science  going on at the Department of  Natural Resources, as well as  across the state that have  contributed.  So what I'm going to talk about  today here, I'm going to start  off by describing global climate  change and sort of sets the  stage for moving towards impacts  on a regional scale.  And then I'm going to introduce  the concept of risk.  So again I've kind of emphasized  this disconnect between what's  going to happen from the climate  side of things and what it  means.  And I think this concept of risk  is a way of bridging the gap  between what could happen and  what it means.  And I'll discuss risk in terms  of mitigation and adaptation.  And then climate change in  Wisconsin.  This will be a little bit more  of a show and tell, I guess, of  different potential impacts of  climate change and what they  mean in terms of specific  impacts.  So the climatic change, as well  as the impact.  And then where do we go from  here. 

 And describing how this fits  into WICCI.  So setting the stage, global  climate change.  Most people have probably seen  this curve before.  This is probably the most  compelling curve in the issue of  climate change.  This is the measurements of  carbon dioxide at Mauna Loa in  Hawaii.  And these are taken by Charles  Keeling, the picture on the  right here.  And these show two things  really.  The annual cycle of carbon  dioxide fluctuations.  So essentially the breathing and  the exhalation of our biosphere.  Carbon dioxide increasing as  plant matter decays, carbon  dioxide decreasing in our  atmosphere during spring and  summer as plant matter grows and    uses that carbon dioxide. 

 One of the things I want to  point out here is Charles  Keeling was only funded to take  these measurements for a few  years.  And if he would have stopped  after a couple of years he would  have had a very interesting  result that describes the  breathing of our biosphere.  But at the suggestion of some of  his colleagues he continued to  take those observations, and  through perseverance we now see  that these annual fluctuations,  while interesting, are small  compared to the overall trend in  carbon dioxide.  So through his perseverance we  end up with one of the most  compelling bits of information  about climate change, and that  is that carbon dioxide in our  atmosphere is increasing.  We do know that it is do to  anthropogenic sources.  That's something that we've been  certain about for a while.  This is a plot of global  temperature.  And each one of the dots is an  estimate of global temperature  for a particular year.  The blue curve is a smooth  version of that and the envelope  around the blue curve is a  estimate of the error.  And so there's two things I want  to point out from this plot. 

 First of all, the global  temperature has increased by  about 7-degrees Celsius over the  last 100 years.  That's, again, something that's  not debated.  We know that the temperature has  increased.  The other thing that I want to  point out here is each one of  these lines here, this red line,  this blue line, the orange line  and the yellow line, is a trend  line starting from a  progressively more recent date.  And each one of these lines gets  steeper and steeper.  So what that shows is that the  rate of temperature increase is  accelerating.  So the temperature increase is  accelerating.  So two pieces of evidence here.  How do we link them together?  One way to link the changes in  carbon dioxide with temperature  is the use of global climate  models.  And global climate models, when  run forward with anthropogenic  forcing, can reproduce that  upward trend. 

 When we don't include  anthropogenic forcing, we can't  reproduce that upward trend.  Which suggests that the upward  trend is due to anthropogenic  greenhouse gases.  I want to talk very briefly  about climate models because  they are an important tool in  assessment.  So a global climate model is  kind of the equivalent of the  weather forecast models that are  used to forecast the weather  only they aren't initialized.  They're run so that the  statistics of the climate being  produced match the statistics of  our observed climate.  One thing about climate models  is they're intended to represent  the equations that govern how  our atmosphere and ocean evolve.  But those equations are not  solvable.  So we have to approximate those  equations.  We have to iterate towards a  solution numerically.  Which means that is we divide  the world into a bunch of grid  boxes. 

 So you might imagine that, for  example, if we have a grid box  over Madison and we want to know  how the temperature is changing  or if we want to be able to  infer something about changes in  cloudiness, we need to know  what's happening upstream.  So these grid boxes communicate  with each other and iterate  forward as, iterate a solution  forward to represent the  climate.  What that means though is that  there's a lot of calculations  that go into these climate  models.  The world's fastest  supercomputers are being used to  run these climate model  simulations and oftentimes the  simulations themselves take on  the order of months.  So this is a massive amount of  computations.  Which means that the more grid  boxes we have, the longer it's  going to take.  So there are problems, so we  have to have large grid boxes  and there's going to be problems  with these models that we need  to understand.  So as we march these models  forward we also, as we look into  the future, we have to infer  something about how our global  economy will evolve over the  next 100 years and there's some  uncertainty associated with that  as well.  So there are three curves here,  the top three curves that I want  to focus on.  The red curve is a projection  from these climate models of how  temperature will change under a  particular scenario of how our  global economy will evolve. 

 And you might imagine this  scenario is sort of the unhappy  scenario where nobody gets along  and there's no sharing of  information and we stick with  the fossil fuel based economy  for the next 100 years.  And we see that the temperature  under that scenario by the end  of the century is somewhere  around 4-degrees Celsius.  And it's still increasing by the  end of the century.  On the other hand there's the B1  scenario here which is this blue  curve where everybody gets  along, this is kind of the happy  scenario where there's lots of  sharing of technology, we move  away from a fossil fuel based  economy and the temperature  change starts to level off by  the end of the century around  2-degrees Celsius of warming.  So the two things I want to  point out here is that by the  end of the century we expect  somewhere 2 and 6-degrees  Celsius of global temperature  change.  But if we look in the next say  20 to 40 years, the time scale  where adaptation where our  systems that we're adapting,  that's relevant to the systems  we're adapting, there's really  no disagreement among these  models.  We're seeing about a degree of  temperature change in the next  20 to 40 years.  So again, these global climate  models, I pointed out that these  climate models have these, one  of the problems with the climate  models is the boxes that we have  to use are large.  And I'll show you an example of  this in a moment here.  So in order to go from a global  climate model to a regional  scale, we need to do something  to the -- of these models. 

 So this is an example of a state  of the art resolution of one of  these climate models on the left  here.  And this is actually, this is  state of the art here.  And so Wisconsin is represented  by about 10 grid points.  This is clearly not good enough  to represent what's going on.  Just look outside any day.  Maybe not today, it's sort of  all gray.  Maybe Wisconsin could be  adequately represented by just a  giant cloud today.  But in general there's all sorts  of stuff going on that's on a  much finer scale than these grid  boxes allow.  So we need to be able to move  from this large scale to the  small scale.  So one of the efforts that we're  undertaking in this part of the  climate working group is a  downscaling of climate models to  a regional scale. 

 And this is work that's being  funded by Focus on Energy, as  well.  So there are a number of issues  of moving from the global to the  regional scale.  This is one of them.  Another issue is what does the  temperature change actually  mean?  I'll get to that in a bit.  Okay, I want to introduce the  concept of mitigation,  adaptation and risk.  So this is the part where I feel  like the university lecturer up  here so bear with me here for a  second here.  Risk, we can define risk as the  probability of an event  occurring times its consequence.  So let's think of an example of  this.  It turns out that if cows get  heat stressed they stop  producing as much milk.  So there is a probability of a  certain amount of global warming  in the future. 

 So let's suppose that above  1-degree Celsius a cow stops  producing, I don't know how much  milk a cow does produce in a  day, so X amount of milk per  day.  Shoot, I should be using more  concrete numbers rather than  algebra up here.  So the probability of exceeding  a 1-degree Celsius temperature  change is our global warming.  The probability of a certain  amount of global warming.  The consequence is a reduction  in milk production.  So let's think about how, so the  probability part of this think  of this as global warming.  The consequence as the impact  system.  So we immediately see that risk  is a concept that links the  climate side to the impact side.  The probability of a certain  consequence of global warming  occurring times the consequence  if it does occur.  Mitigation is some sort of  intervention to reduce the  sources of greenhouse gases. 

 So mitigation is some sort of  intervention to reduce the  amount of global warming.  That's changes the probability  side of risk.  If we reduce the probability of  achieving 1-degree Celsius of  temperature change and that  reduces risk for that farmer.  Adaptation is some sort of a  behavior that adjusts a system  to moderate the damages or take  advantage of opportunities  associated with climate change.  So that farmer, instead of  trying to change the entire  global economy to reduce the  probability of a 1-degree  Celsius change, that farmer  could instead install sheds with  sprinklers in them.  And that way if that 1-degree  temperature change does occur,  the cows can go in the sheds,  turn the sprinklers on and they  aren't heat stressed anymore and  they can still produce milk.  Either one of these actions,  either mitigation, changing the  amount of global warming, or  adaptation, reduces risk to that  farmer.  And that's what, and so risk is  a very powerful way of linking  these two fields.  I'm going to move straight to  this slide here.  Okay, so let's take a look at  adaptation and risk in terms  that we can think of right now. 

 So these are those scenarios of  temperature change that we saw  earlier.  And this B2 scenario is the sort  of best-case scenario.  And so the best-case scenario is  we've got a warming of about  2-degrees Celsius.  Which means we need to be able  to adapt to at least 2-degrees  Celsius of global warming.  It we don't want to achieve a  4-degree Celsius of global  warming then we need to  mitigate.  We have to move from one of  these aggressive scenarios  towards this more benign  scenario.  So as we move into the future  mitigation is not going to be  enough.  Adaptation is also essential.  And also adaptation is not going  to get us to avoid dangerous  climate change either.  Mitigation will be needed, as  well. 

 Okay, so how will global climate  change affect Wisconsin?  I want to show some examples of  some of the changes that we  might expect in the future here.  On the left here I have the  temperature in Wisconsin over  the next, the projected range of  temperature in Wisconsin over  the next 100 years as the dark  red curve.  And then there's that envelope  around it which takes into  account uncertainty in the  models, as well as natural  various in our climate system.  But the overall point of this is  that by the end of the century  temperature changes by 2 to  6-degrees Celsius.  So pretty similar to the global  temperature change here in  Wisconsin.  At the same time precipitation  changes.  This blue curve shows there  isn't much of a precipitation  change.  Maybe a slight increase.  However, the uncertainty around  that precipitation change is  large by the end of the  semester.  [LAUGHTER]  That's great. 

 By the end of the century.  So now although the uncertainty  is large, this is one case where  we know why the uncertainty is  large and we understand why the  uncertainty is large.  It's because north of us things  are going to get wetter and  south of us things are going to  get dryer.  And we happen to sit on a nodal  line of precipitation change.  And so we're uncertain because  some models have us in that  southern region and some models  have us in the northern region.  There's just a little bit,  there's a variation of where  that zero line is.  And we know why that's the case  too.  I'm not going to go into it now.  But this is one of those  unknowns that we know which is  better than the unknowns that we  don't know to, I guess, quote  Donald Rumsfeld.  The other thing that always  strikes me with this is when I  see this plot it means pretty  much nothing to me. 

 If I told you the temperature is  going to change 2 to 6-degree  Celsius what does that mean?  I had a guy walk into my office  and he works for a company that  builds these augers to drill  into thick lake ice, and he  walks into my office two years  ago, not last year, and says  look I got to know if these  winters we've been experiencing  are going to be the norm for the  next 50 years because, if so,  our business has to change its  product.  So that's his question for me.  My comment to him is, well,  global temperature will increase  2 to 6-degree Celsius over the  next century.  That means nothing to him.  There's a disconnect between  what's relevant to him and what  I can provide.  There needs to be some  additional information, there  needs to be some additional  interaction in order for me to  provide information that's  relevant to him and him to  provide me information about  what he actually needs.  Temperature is presumably not  the variable he needs.  This is where WICCI comes in.  WICCI is an organization that  exists at the boundary between  the impact and the climate side.  So what does this actually mean?  We've seen some of these picture  already here this is a plot of  ice cover over Lake Mendota. 

 And this sort of research John  Magnuson has done a lot of this  research over the globe showing  similar plots over the globe.  And this shows that over the  last 150 years or so there's  been a drastic decrease in the  duration of ice cover over Lake  Mendota.  The other thing I like about  this plot here is you can  actually see 1881 where there  was I think 165 or 170 days of  ice cover on lake Mendota.  Every once in a while I see that  and I think global warming  wouldn't be that bad.  But on the other hand I also see  2002 with 20 days of ice cover  in the last decade and that's  not, I don't like that either.  And the impacts of that, of  course, are as we've seen  impacts on the ice fishing.  This is Kites on Ice.  Anybody remember Kites on Ice?  I presume Kites on Ice does not  exist anymore because no one's  willing to risk trucking 40,000  people out on to Lake Mendota in  the middle of February anymore.  And I wouldn't either.  What about this?  Anybody know what this is?  I had someone say a bird. 

 [LAUGHTER]  Know what this is?  I heard someone say it.  Plover?  Yeah, piping plover.  Great, great.  Piping plover.  So these are direct impacts of  ice.  A piping plover lives on  relatively flat shore with  little vegetation.  And ice scours vegetation on the  shore.  So if the ice goes, away the  vegetation grows up.  That's a problem for the piping  plover because that vegetation  is a region where predators can  hide.  And so vegetation is bad for  nesting of piping plovers. 

 piping plover is an endangered  bird in the Great Lakes.  So that ice is not a direct  impact on the piping plover and  in fact the land use change or  development is probably a bigger  impact on the piping plover than  global warming.  However, global warming can  compound existing stressors on  an impact system.  That's something to keep in  mind.  It may not be the dominant  influence but it may be the  straw that breaks the camels  back.  That's my current favorite  research project on the left  here.  And on the right is a plot of  snow versus rain.  So let me explain this plot on  the right.  The blue curve, the dark blue  curve here, is the probability  that something falling from the  sky is frozen.  Or the probability if we have a  precipitation event that that  precipitation event falls as  snow rather than rain. 

 So in the summer here, and  moving into about November 18,  which is our 50/50 day, there's  a greater probability that a  precipitation event will fall as  rain rather than snow.  And as we move into the middle  of winter currently in Madison  there is about 9 out of 10  precipitation events are snow.  Only 1 out of 10 times do we get  rain instead of snow in the  middle of February in Madison.  That's been changing lately.  This red curve is the expected  change by the end of the century  in that rain versus snow.  And we see that in the middle of  winter the change is 7 out of 10  days of snow or 3 days, for  every 10 precipitation events 3  of those will be rain.  So a three-fold increase in the  number of rain days compared to  snow days in the middle of  winter.  The other thing that this points  out is if we define the duration  of winter as the time between  the 50/50 days.  So there's a 50/50 chance before  November 18, there's a greater  than 50/50 chance of rain, after  November 18 there's a greater  than 50/50 chance of snow.  And if we look at the ending  date in late March, we define  our winter season as the  duration of time between those  50/50 days we see that our  winter snow season a reduced by  about two months by the end of  the century. 

 While this isn't good for  tourism it's also not good for  the pine marten, the American  pine marten.  This is the, I always say I  wouldn't know a pine marten if  it came up and bit me on the  ankle.  So the fact that this isn't good  from the pine marten doesn't  come from me it comes from the  scientists at the department,  the DNR and my ability to talk  to them.  So going from a duration of snow  cover to what's important to the  pine marten requires that  interaction again.  So again I'm really emphasizing  the interaction between the  climate scientists and the  impact scientists which can  occur through WICCI.  I'm going to skip through some  of this.  I do want to point out though  that if the winter season is  getting shorter, then the  growing season is getter longer.  So there are tradeoffs.  There are downsides of climate  change but there are also ways  to capitalize on changes.  And we have to be able to adapt  to that as well. 

 Okay, this is a plot of  temperature for summertime in  Wisconsin for the next hundred  years.  The black curve is the median  and the red curve, so this is  what the average temperature  should be in Wisconsin for the  next hundred years.  But we all know that any winter  is different than any other  winter and so these two red bars  show the range of temperatures  based on just natural variations  in our climate.  And so right now the range of  temperature is anywhere from  66-degrees and then a really  warm summer will be 73-degrees.  As we move to 2050, the median  temperature becomes 73-degrees  which means that 50% of our  summers will be warmer than we  have ever observed by  mid-century.  And as we move to the end of the  century three out of four  summers will be warmer than  we've ever observed.  Again, this 73-degree summer  will be an extreme event that  will be on the opposite side.  What does this mean?  Again going from the climate to  what it actually means.  This is not good if you're a  cold water fish.  Cold water fish start dying if  the stream temperatures get  above 19-degrees Celsius. 

 As temperatures warm, the stream  temperatures warm as well and it  those streams no longer support  cold water fish.  Brook trout, brown trout.  And this is some excellent work  that's been going on by John  Lyons and Matt Mitchell at the  Department of Natural Resources.  Heat waves, Dick already pointed  out, increased prevalence of  heat waves.  And extreme precipitation  events.  Now I said that average  precipitation is kind of  uncertain but the  characteristics of precipitation  we think that they're, we're a  little more certain about how  the characteristics of  precipitation may change.  Instead of getting, we expect  more extreme events interspersed  with more dry events.  That's starting to emerge from a  number of different directions  when we start investigating that  problem.  And so the 20 year storm of  today maybe more like the five  year storm of mid-century.  This is Gays Mills two years  ago. 

 This is Governor Doyle surveying  the damage at Gays Mills.  There's no reason that the  rainfall that caused the  flooding in Gays Mills could  have happened in Madison or  Milwaukee.  There's no reason that the  rainfall that occurred in Lake  Delton this last June couldn't  have occurred in Madison or  Milwaukee either.  It just happened that the  convergence was there rather  than over us.  Something to think about.  If that amount of rain, if 17  inches of rain were to fall in a  couple of days in Madison or  Milwaukee what would be the  consequence of that.  Again, this is a sewage overflow  from an extreme rainfall event.  The sewer system in Milwaukee is  a combined sewage system of the  storm water and the actual  septic sewer are combined.  If they overflow, both of them  head straight out into the lake  and that's exactly what you're  seeing here, this plume.  So where do we go from here?  The governor's task force on  global warming was aimed at  mitigation and coming up with  mitigation strategies in  Wisconsin. 

 Now this is important that as a  region we're able to take  advantage of emerging markets  and that we're also poised for  say federal mandates on  greenhouse gas emissions.  And so this is a very important  document and it's a very  ambitious document too.  It provides 63 suggestions on  how to achieve reductions, large  reductions, on greenhouse gas  emissions.  That deals with mitigation.  For climate impact assessment,  again I've been trying to  emphasize this interaction  between physical science, the  impacts and the decision-making  process.  So we need some sort of an  organization that brings  scientists and decision makers  together, and as you might  imagine, I'm going to suggest  that WICCI does that in a very  effective way.  WICCI is the partnership between  the Nelson Institute and the  Wisconsin Department of Natural  Resources, as well as a number  of other state agencies and  campuses across the state and  the goal of WICCI is to assess  and anticipate climate impacts  and develop recommendation and  adaptation strategies.  And as Dick pointed out, WICCI  has these working groups.  And each one of these working  groups is that structure which  allows the interaction between  the climate scientists and the  impact scientists, as well as  the decision makers.  Getting everyone in the room  together is essential for  understanding climate change. 

 We can't do it in isolation.  And so this is why I'm so  excited about this effort.  So I'm going to end with that.  There are some resources here  which will be online, as well as  on the WICCI web page.  And at that point,  I'll take questions.  [APPLAUSE]