cc  >> Thank you all for joining us  this evening.  This is the third seminar  of the Bracing for Impact  Climate Change Adaptation  in Wisconsin Seminar Series.  It's sponsored by WICCI,  Wisconsin's Initiative on  Climate Change Impacts.  For those who are new here,  WICCI is a collaboration between  the UW Madison Nelson Institute  and other departments on campus  and the Wisconsin Department  of Natural Resources.  Today's speaker is going to be  Chris Kucharik.  I want to make a couple of  points before introducing him.  In the back on my right side  here there is a sign-up sheet if  you're interested in any future  events.  And there's also the schedule  for the upcoming WICCI seminars.  And I should mention also that  in case you're not able to make  certain seminars that on the  biotech Web site they are  actually live broadcasting these  events.  Later they'll be on the  Wisconsin Public Television. 

 The actual Web site is:  www.biotech.wisc.edu/webcams  And that's actually on the  yellow schedules in the back if  you want to actually watch a  live feed on the computer.  And later on it will also be  available for later viewing too.  First I want to introduce our  speaker.  I'm very happy to have him here,  Chris Kucharik.  He is a professor at UW Madison  affiliated with the Department  of Agronomy, part of the College  of Agricultural and Life  Sciences and the Center for  Sustainability in the Global  Environment, or SAGE, within  the Nelson Institute  for Environmental Studies.  Chris previously received his  bachelor's in 1992 and a PhD  in 1997 in atmospheric and  oceanic sciences from  UW-Madison.  His work focuses on integrating  field observations and numerical  models of natural and managed  ecosystems to better understand  the influence of changing  climate and land management on  ecosystem services.  His interests include carbon  sequestration, water quality and  nitrate export influenced by  agricultural land management,  climate regulation, biofuels and  corn yield relationship to  climate and farmer management.  His research has been supported  previously by a variety of  private interests in federal  programs including NASA,  the Department of Energy,  Madison Gas and Electronic,  SC Johnson Inc.,  and Wisconsin Focus on Energy.  He served on a subcommittee for  governor Doyle's task force on  global warming and is currently  a member of the Science Council  for the Wisconsin Initiative on  Climate Change Impact. 

 So I'd like to introduce  Chris Kucharik, our speaker.  [APPLAUSE]  >> Well, can you hear me,  first of all?  Is this feed working?  Good.  Thanks a lot for coming tonight.  There's a lot going on around  town, and not to mention NCAA  basketball so I appreciate you  showing up and learning a little  bit about climate change here in  Wisconsin.  And thanks Mike for introducing  me and letting everyone know how  old I was now given my degrees.  So before we go into this talk  tonight, I just wanted to  acknowledge the funding source  that supported a lot of the  research that you'll see  tonight.  That was Wisconsin Focus on  Energy.  And a variety of people up here  who I discussed these results  with and who have helped me  understand better myself what is  actually going on with regards  to climate change across  Wisconsin.  Before we actually move in and  sort of zoom in on the regional  scale and talk about Wisconsin,  I thought we might take a look  back at what's been happening.  Why am I actually here talking  to you about climate change  tonight?  Well, over the last half of  20th century we saw basically  an acceleration of history. 

 Our population more than  doubled.  Our economy grew by a factor of  seven, although I don't know  what the recent changes have  done to that factor.  Excuse me?  >> Do you want questions during  the presentation?  >> Sure, if they're not going to  be...  >> Are these Wisconsin  statistics?  >> These are not, these are  global.  Global scale.  In terms of agricultural, our  food consumption has tripled.  Our water use has also tripled.  And on the energy side we are  using about four times as much  energy now then we were 50  to 60 years ago.  And through all those changes  the planet has taken notice over  the years.  And, in particular, related to  climate change, are the  increases in greenhouse gases  that I'm sure many of you have  heard about over the last half  century. 

 Obviously, carbon dioxide due to  our increase use in energy has  gone up.  Not to mention land use changes  across the planet.  Methane, another greenhouse gas,  has also been increasing.  Methane molecule per molecule  is actually a more potent  greenhouse gas than carbon  dioxide.  And all of these have  contributed to a warming of the  planet and this is the reason  for the climate change.  The global data, and this figure  in particular, shows a long-term  trend in temperature anomalies  each year compared to a hundred  year average from 1901 to the  year 2000.  So if we look starting around  the early 1900s and moving up to  where we are today we've seen  about a .7 increase in degrees  in terms of the global average  temperature during that time.  Which is in comparison to more  recent history, this is a very  rapid change that's been  happening very rapid and is  unprecedented as far as we know.  There have been other sorts of  evidence that have been  supporting changes in climate  across the planet.  Most notably, changes in  glaciers and sea ice extent. 

 I've just put together some  photos historically of a few  glaciers.  This is Muir Glacier in Alaska.  Photo taken in 1941 showing the  extent of that glacier.  What it looks like today,  unfortunately.  Not only has the ice extent  changed dramatically but also  the vegetation that's growing  along there.  Forests have actually adapted to  a warmer climate.  So there's two points of  evidence there.  Another example, Toboggan  Glacier in Alaska, 1909 photo.  And here it is today.  Almost 100 years later or so,  again showing that decrease. 

 In terms of Arctic sea ice, just  to summarize what we've been  seeing, and I'm sure you've  heard about it in the media what  this might do to the ecosystems  in the tundra area, polar bears,  etc.  The red line here, just to  summarize, shows the aerial  extent in millions of square  kilometers of sea ice from 1950  to about the year 2005 or so.  The blue shaded area and that  blue solid line are model runs  that scientists have used to  portray what might happen to sea  ice extent in the future.  And what has them worried is  that the actual rate of decline  through the observation shown in  that red line is much faster,  much more significant than what  the models have been predicting.  So the models in a way have  actually been conservative in  the estimates of that sea ice  extent over the last half  century or so.  The figure on the right shows in  white the extent, the ice mass  in 2007, the minimum extent of  the Arctic ice mass.  The two lines show that red  boundary is the extent on an  average from 2002 to 2006.  And that orange line is the  extent that was minimum back in  the late 1970s.  So you can see how much the  extent of that minimum has  changed just in about 30 to 40  years.  So this is what has a lot of  scientists worried for that  region. 

 But unfortunately, we don't have  glaciers in Wisconsin, we don't  have Arctic sea ice, we don't  have polar bears expect in the  zoo the last time I checked.  So how can we bring this  information down to scale to  make it relevant to not only our  everyday life but to the  policymakers who are going to  making the decisions that affect  the management of our ecosystems  and eventually the economy that  drives this state.  So the idea with our project was  to try to look at how climate  was specifically changing across  Wisconsin to bring it in better  focus for you.  So the way that we've built our  analysis here is based on  long-term observations of daily  weather events across Wisconsin.  Okay?  These are observations that have  been going on for a long period  of time.  We've relied upon the national  weather service as cooperative  observer program.  These are people just like you  or me or our parents.  11,000 of these observers exist  across the US, where they go out  and collect daily high and low  temperature information,  precipitation and snow fall  every day of the year.  This program was started in 1890  under the Organic Act.  And it mainly is meant to not  only support data or to collect  data but also support the  National Weather Service and the  forecasts that are made on a  day-to-day basis. 

 Those data are very important to  our understanding of weather and  climate.  The great thing about this  program is that historically the  instrumentation really hasn't  changed all that much.  Here's a photo around 1930  showing a rain gauge on the left  and an instrument shelter on the  right that houses temperature  and maybe some other instruments  that might be like --  to determine what relative  humidity is.  But if we jump ahead we see that  we basically have the same  instruments today.  We're using rain gauges and  instrument shelters with  temperature, I'm sorry,  thermometers.  So while the precision of that  instrumentation has changed  obviously over the last several  decades, the basis of what we're  doing really hasn't changed all  that much.  And if we look at the spatial  coverage across the upper  Midwest of those co-op stations  we see a great number.  In Wisconsin we have about 220  right now roughly I believe, and  with 11,000 across the country  obviously each state has greater  than 200 as forming a great  network of data that's been  collected across the long-term.  Now the graduate student and I,  or the graduate student that  worked with me on this project,  we set out to try to build a  data set that used not only  these stations in Wisconsin but  in other states too, build this  network or this database for the  state of Wisconsin what we  needed to do was to fill in the  void to get a spatially  continuous data set across the  state of Wisconsin.  And I'm not going to go into the  statistical approach that we  used to do that but what we've  do with statistics and in a  geographic information system is  basically form a grid across the  state of Wisconsin that is  basically 8-kilometer squares or  5-miles on a side. 

 For each one of those little  grid cells we have a continuous  record of daily high and low  temperature information and  precipitation from 1950 through  2006.  The reason we chose 1950 as a  starting point is that was sort  of a maximized a long-term  record of observations.  Not all of the stations here,  the triangles, are the ones that  we used.  The circles were other  observations that were part of  the record, they just weren't  continuous from 1950 onward.  So what we did is it we used  those other stations to validate  or test our interpretation to  make sure that what we were  doing was actually a good way of  doing it.  And ended up writing a paper  about that.  So this is what basically the  crux of everything I'm going to  talk about today related to the  changes in climate across  Wisconsin is based on this  gridded data that we formed.  It's a continuous grid across  the state from 1950 to 2006.  So at any individual grid cell,  we have lots of data.  If you can think about daily  records for temperature and  precip for 57 years, that's a  lot of information to look at. 

 And what I did here was took a  subset for one particular grid  cell to show you in red the  daily high temperature  information and in blue the  daily low temperature  information that would be  representative for all the grid  cells.  So each one of these grid cells  has a continuous record that  we're using through time.  And the same for precipitation.  So I'm going to first summarize  the long-term trends in  temperature that we've seen  across the state in a variety of  ways.  We're going to first look at  annual changes.  Then we're going to divide it up  into daytime highs versus  daytime lows.  And then we're going to look  seasonally at changes.  And as we move across those  scales of time, you'll begin to  see different patterns begin to  emerge.  All the figures that I'm  showing, shades of red, and I  hope that you can see this okay  with the lighting that we have  here tonight, shades of red  indicate places that have been  getting warmer over the last six  decades, shades of blue would be  indicative of trends towards  cooler temperatures during that  time period.  This figure is showing the  annual average temperature  trends across the state of  Wisconsin from 1950 to 2006. 

 So this is representing the  total temperature change on  average during that time period  from the beginning to the end of  the record.  And what we see here are two  points to take home here.  The first is that there appears  to be a very significant spatial  pattern where the highest degree  of warming is going from the  northwest part of the state  through the central part of the  state to the east-central.  And those changes are in the in  order of a half degree to one  degree Celsius warmer from the  1950s compared to today.  You also notice that that amount  of warming is not consistent  across the whole state.  The northeast, in particular,  seems to actually be getting a  little cooler when we look at  the annual average temperatures.  And I wanted to point out that  that overall rate of temperature  change during this time is on  the order of the same degrees as  the global record indicates.  Now when we split this up into  annual temperature changes  between maximum daytime highs  versus nighttime lows, we see  that there's some differences  begin to emerge.  The daytime highs don't seem to  be getting as warm, or not  warming as quickly as the  nighttime lows are.  So daytime highs maybe are  getting a half degree warmer  across the state, nighttime lows  are warming by about a half to  two degrees. 

 So there are some significant  differences there already  between the rate of warming that  we're seeing across the state.  And again these changes are not  spatially consistent.  There are some regions that are  obviously getting warmer than  others.  Now the real interesting story  comes when we start looking at  the breakdown of the seasons.  We split up these trends for  daytime highs between winter,  spring, summer and fall we begin  to see that significant amount  of warming is taking place  during winter and spring.  But during the summer and the  fall we actually have large  portion of the state that have  seen a trend towards cooler  daytime highs during those  seasons.  And if we look at the nighttime  lows we see now everything is  plotted on the same scale here  in terms of minus 1.8-degrees  Celsius change on the cool end  to 1.8-degrees of warming  on the high end.  So you can see that during  winter, spring and summer for  nighttime lows, the reds are a  lot deeper meaning the magnitude  of that change is quite a bit  greater than what he saw for the  daytime highs.  Okay?  We also see a little more  consistent warming in the  nighttime lows through all of  the seasons comparatively to the  daytime highs that I showed in  the previous slide.  So the first conclusion is that  the greatest amount of warming  is occurring during winter and  springtime seasons. 

 Okay?  Now if we compare the seasons  where we saw discrepancy of the  trends in temperature, the  nighttime lows versus the  daytime highs in summer and fall  show the largest discrepancy in  terms of the direction of those  changes.  We note that nighttime low  temperatures seem to be warming  faster than the daytime highs  do.  Okay?  So in essence what's happening  is we're compressing the diurnal  temperature range in these  seasons.  And while this graph might look  a little bit busy, I promise  I will explain exactly what I'm  plotting here.  I went decade by decade and  plotted the average difference  between the daytime highs and  daytime lows across the state.  And what seems to have happened  is that diurnal temperature  range seems to have peaked  somewhere in the 1960s, 1950s  and 1960s, or during summer that  average temperature range was  somewhere between 12 and  15-degrees Celsius across the  state.  By the time we get down into the  beginning of this century, that  temperature range or difference  between daytime highs and lows  has now shrunk to 9 to  13-degrees, a change of about  2 to 3-degrees Celsius.  So like I said, the diurnal  temperature range has compressed  a bit during the summer and  while 2 to 3-degrees of change  in the diurnal range may not  seem like a lot that is actually  is a very large change on a  short period of time across our  state.  That has undoubtedly had affects  on ecosystems and water  resources.  Now, unfortunately, I don't have  a cool figure like this  pertaining to Wisconsin or  Madison. 

 I happened to find this  this week.  This was a study done for  Cleveland, Ohio, but it's  showing exactly the same thing  that's happening here in  Wisconsin.  What this researcher did was  plot for each decade at that  city based on those long-term  observations, the differences  between the daily high and daily  lows, by decade.  So you can see as time has gone  on those differences have  decreased through time.  So the average high for each  decade, and this was done over  the whole year, has gone down a  little bit.  And the average lows have been  warming a little bit causing  that compression of the diurnal  temperature range.  Now why might that be happening?  Why might daytime highs not be  warming as quickly or getting  cooler compared to nighttime  lows?  Well, a lot of climatologists  believe it has to do with the  amount of moisture in the  atmosphere or the amount of  cloudiness that persists or  exists.  Now if you know anything and you  pay attention to weather  forecasts here in the Madison  area sometimes you might hear    well, it's going to be cloudy  tonight so that's going to help  keep temperatures a little bit  warmer than they would have been  if the skies would have been  clear.  A better example I might be able  to give would be the differences  between Arizona and Florida.  Now has anybody been to Florida?  I have. 

 I'm sure a lot of us have taken  a trip there.  Did you ever wonder why the high  temperatures there during summer  never get much above the low  90s.  Versus in Arizona, which is  about at the same latitude, you  end up with high temperatures  sometimes above 120-degrees.  Well the reason is the amount of  moisture that's in the  atmosphere in those two places.  Arizona is a very dry place and  Florida is a very humid place.  And it takes a lot more energy  in a more humid environment to  not only raise that temperature,  and at the same time more humid  air does not release that energy  as quickly.  So that, we believe, might be  the link to what is going on  here.  It may be an indication of more  moisture in the atmosphere.  And when I show you trends in  precipitation you might  understand a little bit better  why we might be seeing these  trends across our state.  What's more fascinating to me  and my colleagues, long-term  average temperatures are very  important to study, but it  really is the extreme events  that all of us are going to have  to deal with. 

 It's really the changes in the  extremes that are going to cause  problems for us.  And what we've done is taken a  look at extreme temperature  trends across the state.  We've looked at the number of  days each year where the daily  high temperature is above  90-degrees, and climatologically  this is a map showing that  across the Northwoods typically  we might see one to two days  every year where it is 90 or  above.  In the southern part of the  state maybe the average is  somewhere between 7 and 11 days.  In Madison that number is about  9 days each year we get to 90 or  above.  On the flip side, really cold  nights, temperatures that are  below zero, the frequency that  those actually happen  climatologically, about 40 to 45  days every year in the north  woods the temperature is below  zero Fahrenheit.  And across the south and  southeast near lake Michigan,  maybe only 15 days.  As an example, Madison for this  past winter, or I guess spring  starts Friday but we're still in  winter I guess as of this  evening, we had I think 23 days  below zero here for the last  winter.  And while you might have thought  that that was actually quite a  cold winter it actually isn't  too far off for what the  long-term averages are.  That's about the number of days  that we should be seeing each  year with temperatures below  zero at night. 

 So what we've do is looked at  the trends in both those really  cold nights and the really warm  days through time.  So on the left is the trend in  the total number of days each  year where the nighttime  temperature has gone below zero.  And what we've seen is that  those very cold nights are  occurring much less frequently  through time.  Maybe one to three weeks less  from the 1950s through just the  last decade or so.  So those very, very cold air  outbreaks are happening less  frequently, particularly in the  central and the northwest parts  of our state.  On the flip side, the total  number of days each year that  we're seeing with highs above 90  Fahrenheit, there's been very  little change across these last  60 years or so.  And in fact, there's some  places, particularly in the  southwest, through the central  part of the state let's say that  might actually be seeing a  little lower frequency of those  very hot temperatures.  The reason I bring this up and  why it's important is that in  the future global climate models  or global circulation models  that are used to predict what  the climate is going to be like  by the end of the century  suggests that the number of  these hot days is going to go up  significantly.  And up until this time the  historical record does not show  this trend.  So at some point in the future  we may hit a tipping point where  we do see an increase in those  very hot days. 

 But up until this point in time  we do not see that trend occur  in the historical record.  Now you can only imagine that if  we're seeing quite a few changes  in those very cold nights during  the winter and the early spring  that we've seen changes in the  growing season also.  Across the state of Wisconsin  our average growing season is  somewhere around 130 days, in  the northern part of the state,  to about 160 to 170 days across  the southern part of the state.  And that is defined by the  number of days between the last  day in spring when we hit 32  Fahrenheit and then the first  day in fall when we hit 32  Fahrenheit for a low  temperature.  On the left in this figure is  the change in the date of last  spring freeze, the overall  trend.  What we're seeing is that there  has been a one to maybe three  week retreat in that occurrence,  meaning the last spring freeze  is happening a lot earlier than  it had been previously.  And on the right is showing the  change in the date of the first  fall freeze.  And to summarize that we've seen  a one to may be two or three  week retreat later for that  occurrence to be happening.  Particularly, in the central and  the northern part of the state.  So if you put those two together  they're going to define what the  change has been in growing  season across the state of  Wisconsin. 

 And this is what really blows my  mind is that just in the last 60  years or so we've seen an  increase in the growing season  of one to four weeks across the  central and the northern part of  our state.  That's a really big change in a  very short period of time.  And it's undoubtedly a change  functioning of ecosystems,  forestry, agricultural, how  water is cycled between the land  surface and the atmosphere.  So this is something that we  really need to take note of and  wonder whether or not that trend  is going to continue well into  the future or not.  There's also other indicators,  mainly ecological and biological  systems.  I'm only going to briefly touch  upon a couple of the key things  that have been talked about  because I don't want to take the  wind out of the sails of future  speakers of this seminar series.  They're going to talking a  little bit more about these in  depth.  The first is the work of John  Magnuson and colleagues at the  Center for Limnology here at  UW Madison showing the downward  trend in the ice duration on  Lake Mendota.  The overall trend here suggests  that the number of days of lake  ice extent on Lake Mendota is  decreased by about a slope of 19  days less per 100 years.  Now this is a very significant  change and obviously is related  somewhat to those changes in  those very cold nights, as well  as changes in the growing season  across the state. 

 Another example that I found  just by poking around the  Internet, now I don't know how  many of you have been up to  Madeline Island up on Lake  Superior there, but they run a  ferry during the warm weather  months between La Pointe and  Bayfield.  And during the wintertime the  locals there rely on an ice  road, basically driving their  vehicles across the ice on Lake  Superior to get from one place  to the other.  And these are just some  photographs of that.  I think it's like 2 or 3 miles  distance from one point to  another.  They've been collecting data on  the number of days that they can  actually drive their car across  since I think the 1960s.  And what the trend there is  showing is a significant trend  downward on the total number of  days that ice is thick enough  for them to actually drive.  And in fact, there have been a  few years just in the last 10  where there have been very  little.  No days, I think it was '97-'98  where we had a very strong  El Nino, we had a very warm  winter across Wisconsin and a  few other years.  This is really astonishing to  see that kind of a change in  such a short period of time.  On the biological side and also  ecological side there have been  indications of changes in  phenological events for both  basically blooming of plants and  then arrival of different birds  back to Wisconsin in the  springtime. 

 And Nina Leopold Bradley, who is  Aldo Leopold's daughter, carried  on work that Aldo Leopold  started back in the late 1930s  where he was documenting the  arrival of birds and also the  blooming of different flowers  and plants.  She kept a database from 1976 to  1998 and published a very  important paper in the  Proceedings of the National  Academy of Sciences in 1999  showing these trends.  And these are quite interesting.  I just picked a few.  She had lists of 30 or 40 or 50  different types of species of  birds and plants, maybe even  more than that.  But the differences just over  those decades showed geese were  arriving almost a month earlier  towards of end of that record  compared to the beginning of  that.  The cardinal and the first song  maybe three weeks earlier.  Robins arriving maybe a week to  10 days earlier.  And several types of plants that  were blooming maybe two to three  weeks earlier towards the end of  the 21st century compared to  right before World War II  when Aldo was collecting data.  So that overall trend suggests  that there's about a 1.2 day  earlier per decade trend  in those events happening  in the long-term. 

 Now I thought it would be  interesting to try to match up  the climate data that we have to  see if indeed these responses  were correlated to trends in  temperature across the state.  So what I tried to do was pick a  sort of indicator that signifies  of the onset of spring.  And for all practical purposes,  I kind of just made this up.  But there is some reason behind  it.  There actually is some reason  for picking what I did.  I looked at the running 10 day  mean temperature, what day did  that running 10 day mean  temperature reach 50-degrees  Fahrenheit in the springtime.  50-degrees Fahrenheit is an  important basically threshold  for germination of seeds of  crops in the ground.  That's mainly the reason why I  picked that.  What we, and it's an indicator  of consistent early season  warming.  Rather than just picking the  last spring freeze date, this  sort of is more, signifies more  of a consistent warming in  springtime. 

 What the graph shows or the  figure shows is that the onset  of spring is arriving sooner  across the southwest two-thirds  of the state maybe one week to  10 days earlier, and that  happens to match up very well  with the trends in those  phenological events that Nina  Leopold Bradley was documenting.  So I believe that those are very  much responding to these changes  in climate over the long-term.  The other interesting thing  about this figure that I just  noticed discussing with a few  colleagues is that the northeast  and the north central aren't  showing as much of a change as  the southwest two-thirds of the  state.  And if you were to draw a line  kind of along that, that happens  to significant the ecological  tension zone across the state of  Wisconsin.  Sort of dividing the northern  forests in the northeast to the  southwest prairies, oak savannas  and agricultural lands that we  have.   And John Curtis who published a  book in 1959 called Vegetation  of Wisconsin uses several other  indicators of climate to sort of  outline this particular boundary  that seems to be showing up and  how our climate is changing  today.  So I found that to be quite a  bit interesting to too.  When you dive a little bit  deeper into the details some  interesting things emerge.  So I've talked a lot up until  this point about everything  related to temperature, but  obviously with everything that's  been going on with our climate  the last couple of years,  flooding is on everyone's mind.  It's definitely on my mom's mind  right now who's got sump pumps  running in her basement  continuously due to elevated  groundwater. 

 We're going to look at long-term  trends in precipitation across  the state and see if we can make  some sense over what's been  happening with those quantities.  So as background on average this  is a plot of the 30 year normal  precipitation across the state  of Wisconsin produced by the  National Weather Services office  in Sullivan.  What you can see is that on  average Wisconsin gets somewhere  between 28 and 38 inches of  precipitation each year.  But unlike maps of temperature,  you might notice that there's a  lot of variability in these  numbers across the state.  It's very spotty.  Obviously across the southwest  we see a lot higher amounts, in  the northeast a little less.  That's just the problem with  precipitation, it's a much  variable quantity to try to  measure.  It varies a little more widely  across the state, in particular  between the months of let's say  late April through September we  get quite a few thunderstorms  across the state of Wisconsin.  A lot of our precipitation comes  from thunderstorms.  Thunderstorms happen to occur  not always widespread across a  region, and that contributes to  some of these discrepancies and  differences we see from region  to region or county to county. 

 I thought it would be  interesting just for my own  personal interest to look at how  many days does it actually rain  in Wisconsin.  And defining rain as measurable  precip greater than 100th of an  inch measured by those co-op  stations.  And what we find is in the  northeast part of the state it  rains about maybe 140 days where  we're measuring precipitation.  It's a little bit elevated.  This area up here is in the snow  belt of lake superior and so  during wintertime they get a  little bit more frequent events  of precipitation due to cold air  moving over the lake there.  Across the southwest part of the  state maybe about 110 days.  I think the average in Madison  is about 120 days of measurable  precip.  So that means actually about one  out of every three days it's  doing something.  That seems a lot to me.  So it's very frequent. 

 Unfortunately these shades do  not show up very well in this  light, but it's shades of green  which look like gray on the  screen here are going to places  that are getting warmer, I'm  sorry, getting wetter over the  last 57 years.  Shades of dark brown are places  that are getting dryer.  So immediately on an annual  average we see about a 2- to  6-inch increase of precipitation  across the state.  It's about 50 to 150 millimeters  for those of you who only work  in the metric system.  So that's a pretty significant  increase over the last several  decades.  There is a hint just in the  annual totals of a trend towards  a little bit dryer conditions in  the north and I'll get to that  in a minute.  If we look at these changes  seasonally, what we have in the   upper left is springtime trends  in precipitation.  Summertime in the upper right.  Fall in the lower left.  And winter in the lower right. 

 All in all you might take a look  and say there's a lot of green  shades on there, there seems to  be a lot of places during all of  these seasons that seem to be  trending towards wetter  conditions.  The thing to note is that the  magnitude of those changes is  not the same everywhere.  And the spatial pattern is  obviously a bit different from  season to season.  So the one key thing that sticks  out though is this summertime  decrease in precipitation across  the northern part of our state.  It's the one area that appears  to be getting dryer over the  last six decades or so.  And if you think about all the  lakes that are in that region,  the recreation and tourism going  to that area, that could be a  big problem if that continues in  the future.  And in fact, just in the last  couple of years they've been  basically under a significant  drought.  And this photograph I got from  Dick Lathrop, who works for the  DNR, shows a lot of dead wood  that's been exposed in Lake  Fallison or Fallison Lake that  used to be covered up by water.  And this will be coming a more  consistent problem, not only in  the north but also in the  central area of our state too.  And it might be due to this  decrease in summertime  precipitation of about maybe one  to three inches during  summertime. 

 So on the flip side, I'm talking  about dryer conditions while  most of us have been bombarded  with things getting a lot wetter  it seems over the southern part  of the state over the last  several decades.  And I'm going to touch upon a  little bit on the recent extreme  precipitation events in the  flooding that we've seen in 2007  and 2008.  Just to refresh everyone's mind  going back to August of 2007, if  you remember, southwestern and  south central Wisconsin was  unfortunately positioned just to  the northeast of the stationary  front.  That was feeding a lot of warm  moist air over that.  And it rained like heck across a  large part.  And this is a radar image or  estimated precip from the  weather service shows that band  of heavy precip from the  La Crosse area through Madison  down into the Racine area.  And that caused all sorts of  flooding problems.  Gays Mills and those other  communities in the southwest  part of the state were dealing  with that flooding.  Then came along the winter of  2007 and 2008.  And we set all sorts of snowfall  records here in the southern  part of the state. 

 Over 100 inches of snow in  Madison, an all time record.  We had all that snow pack  sitting around, melting in the  springtime, that elevated a lot  of the groundwater tables, lakes  and streams.  And then we were hammered again  in June with that unprecedented  widespread flooding event of,  basically these amounts of  precipitation for a week are  like how much precipitation we  might get for the whole summer  across a region.  And if you were paying attention  to the news and all that you  know what happened at Lake  Delton and then Baraboo and Sauk  County area that got like 14 to  16 inches of rain in about a  week there.  And that was quote, and I'm  going to use numbers that were  my friends that are a the  hydrology people, say that was a  one in 500 year event for  rainfall.  So supposedly we're not supposed  to see that kind of event for  another 500 years.  Well, we don't know exactly when  it's going to happen but we hope  not anytime soon.   But the key here is that we've  seen a little bit of maybe an  indication of things that might  be happening more frequently in  the future.  Now just for today's talk I  thought it would be interesting  to look at the average  likelihood across the state that  we might see a rainfall event  greater than one inch.  That would be called an extreme  event, one inch, two inch, three  inch and beyond that. 

 So this is the sort of  probability across the state  that for any given precipitation  event that you have in a given  year what's the likelihood that  it's going to be greater than  an inch or so.  So what we see across the state  is that the southwest has a much  higher probability, maybe 6% to  8% likelihood of seeing an event  of one inches or greater.  That likelihood decreases quite  a bit to the northeast part of  the state.  Maybe only a 2% chance if you're  in Oconto County or near the  Green Bay area of seeing an  extreme precipitation event of  that magnitude.  So there seems to be somewhat of  a split between the northeast  again the southwest part of the  state.  The southwest, let's say,  two-thirds of the state seems be  better positioned, I shouldn't  say better positioned,  unfortunately positioned to get  heavier rainfall events.  Now it happens to be that this  week is flood awareness week in  Wisconsin as proclaimed by the  governor and the weather  service.  And the weather service put out  this very interesting map of the  total flood events from 1982 to  2008 across the state.  It might be hard to read,  there's three numbers that are  plotted there.  It's the number of the events,  deaths and injuries occurring. 

 So what's interesting from those  reported data the same type of  split seems to be correlated  with the type of statistics that  I've shown here.  That obviously the southwest  parts of the state are more  likely to see these flooding  events through time.  Now when we talk about maybe  changes in climate or the  frequency of these events, the  National Weather Service on  their website put up some very  informative lists a few months  ago about, excuse me, the top 10    24-hour precipitation records,  on the left for Milwaukee for  their entire observation record  compared to Madison.  I've highlighted in yellow those  events in those top 10 lists  that have occurred generally in  the last 10 to 20 years.  So in Milwaukee there's actually  been four of those top 10 events  have occurred just since the  year 2000.  And in Madison six of the top 10  events have occurred just since  the year 2000 also.  So that's a little bit of a  concern there.  That we've seen in the last  decade to be seeing an increased  frequency of these very heavy  rainfall events.  Now if you look at the top event  for Milwaukee compared to  Madison, Milwaukee's top event  was 6.8 inches back in 1986.  It flooded County Stadium where  the Brewers played. 

 It was just a real mess.  I happened to live in the  Milwaukee area at that time.  Madison's all-time top total  there is 5.3 inches.  So there's an inch and a half  difference between the top  events just in those two cities.  These two cities are highly  urban areas.  We have problems with runoff.  We have a lot of pavement.  We have a lot less soil where  that water can infiltrate before  it runs off and creates urban  and small stream flooding.  But what's interesting is that  just because we've only got  maybe five or six inches as our  top event doesn't mean a higher  event couldn't happen.  And just by luck we haven't seen  a higher precipitation event. 

 And the examples that I'm going  to point out happen to be in  August 2007 where the  observation stations at  La Crosse and Vernon had 11  and 12 inches, respectively,  as their top events.  Now if you could imagine if  those events would have happened  here in Madison or Milwaukee,  which would have been double  over what the all-time event  was, what that would have done  to infrastructure, water, etc.  Runoff, sewage problems, you  name it.  It would have been catastrophic  probably.  So I guess my point is just  because we haven't seen it here  in one location, the problem  with precipitation is because  it's highly variable at any  given time and across space it  can happen again because it has  happened in other places.  Yeah?  >> Is it close to the all-time  anywhere in the state?  >> I don't know about that.  I just picked those due to the  observations that I could get my  hands on from 2007 due to that  flooding event.  So I would say those are likely  near the top I'm guessing.  So just to sort of summarize  just in the last couple minutes  here.  What do I want to you to take  away?  I through a lot of data at you. 

 A lot of things that might be  surprising; a lot of things that  might be confusing.  So let's just summarize sort of  the key points.  The most significant warming  across the state has been at  nighttime low temperatures  during winter and springtime.  And that area of focus has been  from the northwest through the  east central part of the state,  the core of the greatest  warming.  We've seen a trend towards  cooler daytime highs it seems in  summer and fall over this period  and we've discussed some reasons  why.  It might be due to those  increases in precipitation and  more moisture that have  compressed that diurnal  temperature range in summer,  particularly.  So we see that the diurnal  temperature range has decreased  particularly during summertime.  Seasonal precipitation trends  suggests that we're overall  receiving maybe 10% to 15% more  precip than we were 50 or 60  years ago.  But there's one exception to  that rule, northern Wisconsin  appears to be trending towards a  little bit dryer summers during  this time period.  And the record rainfall events  of just the past 10 to 20 years  a rapidly moving up these  all-time top 10 lists. 

 And whether that's a blip on the  radar screen or may be a sign of  things to come we need to really  pay attention to that.  Because I'll tell you the  climate models that are used to  predict the future suggest that  those extreme precipitation  events are going to be occurring  more frequently in the future.  And that the northeast portion  of our state appears to be less  likely to see those extreme  rainfall events, at least in a  climatological sense.  Whether or not that pattern  continues into the future,  we don't know.  But we will be studying that in  future studies.  So a point that I'd like to  make, and sometimes this isn't  such a great thick to say when  you're trying to get people to  buy into the idea of climate  change, our state is necessarily  getting hotter but it's getting  less cold.  Those day time high temperatures  90 and above, we're not really  seeing an increase during summer  of it getting a lot warmer, a  lot hotter.  It's really on the cold end of  things.  It's those really cold nighttime  lows that are getting warmer.  Why is that significant?  It's significant, do you like to  ski, do you like to go ice  fishing, do you like to go  snowmobiling, do you like to be  outdoors, do you like the  Birkebeiner?  If those really cold nights  continue to decrease we're going  to see, the Northwoods in  particular, tourism and  recreation go down the tubes  potentially. 

 So I make a statement like this  with caution but it does have  some important, I guess, message  to get across that these trends  are very important to our  livelihood here in our state and  to our economy.  And I'd like you, when you leave  the room, to think climate  change and not necessarily think  global warming.  Global warming, I will accept it  as a term because it has so much  momentum in the media, but  unfortunately it kind of glosses  over what's really happening.  It really is that the climate is  changing.  And global warming, it's not a  one size fits all, as you saw  here today.  There are places geographically  across our state and across the  whole US and the world that  might get warmer.  There are places that might get  cooler.  There are places that might get  dryer.  There are places that might get  wetter.  And so it is a lot more  complicated than just saying  global warming. 

 Just think of it as climate  change, and we've seen  documentation of that today.  If you do want to get more  information about this, I would  encourage you to contact me  through email or give me a call,  and I'm also plugging obviously,  this is the third in a series of  nine talks related to climate  change in Wisconsin.  The speakers after me in the  series will start to look more  closely at the impacts that  climate change might have on  natural resources, ecosystems,  and other things across the  state of Wisconsin.  So I appreciate you listening to  me babble for 50 minutes, and  we've got time to take questions  so thanks a lot for listening.  [APPLAUSE]