join us for in-depth, the first sunday of the month at noon eastern. that's the tv on c-span2 next, i'll look at mother nature. james elsner says the increasing ocean warmth is making hurricanes stronger and tornadoes have a more powerful punch. he discussed the future of storms. his speech is one hour. >> thank you. i only wear one hat also. i really think of myself as a scientist. that's all i do. if you do science for a long enough time, they put you in positions like being the chair of the department so it's not something that you seek out, but it's something that happens be to yo because you do a lot of science. i like to think of myself as a

person who just focuses on one thing. actually it's two things. it's hurricanes and tornadoes. i focus on two things, but there really connected in that they are these violent wind storms that caused lots of damage and casualties and we have to think about what might happen in the future. really, what i do, this is this idea of wearing one hat. i spent all of my time thinking about what hurricanes and tornadoes might be like in the future. you will see a lot of graphs today. that's the way we make comparisons. science is about comparing this with that. that is the window to understanding science.

i want you to know these are my graphs. these aren't graphs i got off the internet. these aren't someone else's arguments about what's happening and there are a lot of argument arguments. what you are going to hear from me is what i do and what i think about on a daily basis. before i begin, i would like to thank her for inviting me. i got a chance to to her the facility with doreen this afternoon, a wonderful facility. this is really an outstanding facility that should be very proud of. a large part of the reason for that is because what felicia's been able to do over the past decade. as she said, we have ten or 12

faculty, depending on how you count, but it's very dynamic and increasingly associated with what folks do down here at the marine lab. i'm to start out with hurricane hurricanes. if you kind of drift off in this talk, and you might, when i get to tornadoes, you know i'm about halfway done. i'll talk about hurricanes to start out. you are obviously familiar with hurricanes in a generic sense. we can track them and look at them from space and they are these powerful things. we know what they're like today. last year we had a hurricane come very close to this part of the world so they are in our consciousness constantly. when, where, how often, those are the things we know about. what about the future?

are we in for a greater risk of these storms? unfortunately there is just no simple way to get answers to these questions. they're very him important, there's just no simple way. why is that? why can't we just do some kind of calculation on the back of the envelope and work it out. well, first of all the theory is very limited. we don't have a theory of climate. someone said this is the theory of how climate works. that's nonsense. we have theories of how things work but we don't have a general theory of how climate works. we certainly don't know everything that drives the weather. models which are good at forecasting where a hurricane might go, given that this one out there they don't really represent the atmosphere in an adequate way, at least on a

scale of climate. finally, we don't have enough data. we don't have a way to look back in the prehistoric times. it's very difficult to look back. we just don't have enough data. then the data we do have varies in quality. social media is not going to help us out. you will hear a lot of opinions and bickering so what is the solution? how does jim elsner spend his days? i tried to put things together. i tried to put the theory together with the models and the data. i'm in a talk about two theories today. i'm to talk about thermodynamics and statistics. these are the two theories that allow us to get some answers about what hurricanes might be like in the future.

you probably aren't physicists or statisticians so i'm not going to go that deep, but these are the deep structures in which we can hang our hat on to try to understand what might it be like in the future. so. this is my slide from popular make mechanics. it basically describes how the hurricane operates. what you want to keep in mind are a couple propositions. in up and out. that is the circulation of a hurricane that you are probably not aware of. you think of circulation like this, you think of these things is spinning. that isn't the circulation that drives the hurricane.

the in part is where the air comes in at at low levels near the ground near the ocean surface and it gets its heat and moisture and it rises in the center of the hurricane and also in all of the other thunderstorms surrounding the hurricane and that it exhausts at a higher level. it takes in heat at high temperatures and exhaust the heat at much lower temperatures. it's almost exactly opposite of your refrigerator. that's how things take hold in your refrigerator. your exhausting at high temperatures. here you are exhausting at low temperatures. this is what we call a heat engine. this is an extremely efficient heat engine. they describe the hurricane as a heat engine.

it's a matter of converting the heat and moisture of the warm ocean into the wind you feel circulating. in, up and out. that is a theory that based on things that were worked out in the 18th century. with that heat engine theory, we can work out how strong the hurricane can get. i'm in a use this to kind of abbreviate how strong can those winds actually rotate. 60 miles per hour, 80 miles per hour, 150 miles per hour, that's the speed or the maximum potential intensity. that is just related to how warm the ocean is. it's an abbreviation for how warm the ocean is. the warmer the ocean, the higher the intensity of the storm.

more motion, more energy and so this is a basic theory. he has worked out this theory of how hurricanes get strong and they're maximum potential is derived based on how warm the water is. so you feel that heat, that is the heat because of this theory that drives these hurricanes. you said that's kind of simple, right we can figure out how warm it will be and we can figure out how intense the storms are going to be. if you're thinking ahead, why is this so complicated? the warmer ocean, the more energy. turns out, first of all you have this denominator which is the upper-level temperature. the colder it is also the stronger the storm can be. so warm at the surface, cold

air loft, you can get a very strong hurricane. you can get an arctic hurricane if this is cold enough. but still you say he's got everything done. why does he need, he's got his theory here, gary emanuel is his friend, he can work this out. here is the problem right here. the thing here is that the hurricane start to mix up the ocean and we produce all sorts of sea spray and there's a lot of complexity that's going on. it's not clear how much this is going to go up. that's what we want to know. we know the oceans are warming up. they are warming up due to greenhouse gases affect.

there are warming up and we should get stronger storms. how much stronger? who knows. we can't work it out. we simply cannot work it out because of these air fluxes. that is one theory. just to review. in up and out, the theory of how storms intensify through the heat engine. your car has an engine, it works on simple ideas. it's not as a efficient. let me see if i can humor you a little bit on this. you said statistical theory that was worked out in the mid- 20th century, suppose for example we record the

highest speed in ten hurricanes. let's say god to 34 and a half meters. second. i'm a scientist. i apologize for that already, but that's what we use. if you need to convert it, it's about 60 miles per hour. if it had a massive intensity of 44-point to, we can do this. you can imagine doing this. for each hurricane simply tell me how strong. i'm in a put all those down here. this is the set of ten wind

speeds for the past ten hurricanes. we can order these. this is just how they occurred in time. this is more interesting from a statistical point of view. we said let's put in order, this is the weakest and this is the strongest. this tells us that 20% of the hurricanes over these past ten have winds of aches seated we have 10% that exceeded this amount. we have percentages and we have threshold wind speeds they make statisticians drool. they can connect the dots into the theory. this gives us a limiting, from

cary emanuel siri, we can work out the maximum potential and from statistics we can work ou out -- we have two different intensities. we can look at how strong they got. this is how fast they are rotating. then we can just plot them and you can see these black dots represent that. notice what happens to those black dots. they start to flatten out. at some level you can't get a stronger hurricane. that's right at 75 meters. second. that's what i mean by limiting intensity. that is a brilliant statistical theory.

it tells us about what is the maximum you can get given the set of values you have. think about that. if i measured the height of every one of you and then ranked them from shortest to tallest, i would have a single tall person in this room but i would not say that the tallest person that could ever be in this room. but i want to know that. i want to know what would be the tallest. what i would do is i would have another lecture next week. i'd get another 25 people, i get a different group of people and i get another tall person and then i'd have two pultall people. that's what i'm doing here. i'm getting all the tall people and i'm setting a curve to that and i can then extrapolate to get the possible tallest person. that's wonderful theory. it's embedded in the

mathematics of statistics. so i've got two things going on. i have this limiting intensity which is a statistical quantity that we can used to compare with the theory of maximum potential intensity so hopefully you're staying with me. i have this maximum potential and the statistical intensity from statistics. how should we make that comparison? it turns out that these limited intensities, it isn't that important. it's how limiting intensity changes with the ocean temperature. that is the key component. so how do we get this? it turns out, hurricanes it's clear where the temperatures are uniform. this is all the hurricanes in one season.

i didn't label what season it was because i want to test my students, what season is this? it was a pretty active season. 2004 is an excellent gas because they look very similar. so, you notice underneath the tracks, each of these white lines they are a series of hourly dots where that hurricane was. underneath that are the ocean temperatures and you can see they don't all occur over the same ocean temperature. what we can do with the new space, i was trained as a scientist but i really became

a scientist when i became a geographer. the reason is, although this is an important discipline to understand how the atmosphere works, geography allows you to put pieces together. it allows you to leverage space. it allows you to think about things spatially. when you start leveraging space you can get a lot more bang for your buck. let me show you what i mean. here is, we can grid up the domain. we can recognize florida here, this is where hurricanes form and we can look at, for example, to hurricanes and they are great until they get one of the hexagons and then it turns black or it's not

hurricane until it gets to black but it has hurricane intensity. so it's a weak storm and then becomes a hurricane. what i can do is i can simply count how many hurricanes occurred in each of the boxes. this is another key component of my talk. i want you to keep in mind the difference between the frequency of storms and the intensity of storms. this is a key idea of trying to understand what might happen in the future. i'm going to count them right here. these boxes had one, these had to, everywhere else had no hurricane. i can do that for all the hurricanes that have occurred over many years. this is a fifty-year plot. we can see where hurricanes are most common in this box here and i bet this box comes as somewhat of a surprise to you.

this is where more hurricanes occur than here. more than here, more than here, more than here. there's more hurricanes here and here than there are in here. it's not about only frequency. it doesn't give you the answer that you might think. now i can do this, it gets a little complicated but just humor me for another five minutes. 1981 through 2010, this is simply the number of hurricanes that have occurred in these boxes over that time. the darker blue indicates more hurricanes and the lighter blue is fewer hurricanes. two hexagons, c&d. within each of the boxes i can tell you how strong the hurricane was one within that box each hurricane gets to

have one value when it goes to that hexagon. this plot probably looks more familiar to you. this is where their frequent, this is rather strong. this represents fewer but stronger. fewer, stronger. more, less intense. more hurricanes, not as strong. that is the key to this puzzle the future might have to be about fewer but stronger. i know that doesn't sound like he's going to tell you whether my house is going to get hit. i don't work at that scale. what i work at is the scale of trying to understand how the climate conspires to create

hurricanes so this is how i work it out. i have these two boxes and i can say, for example for boxy where there's fewer of them, i get stronger intensity. for d, where there are fewer but stronger. this is only about 50 meters. second this is over 70 meters. second. i only have limiting intensities now. i have this nice spatial geographic, meteorologists would never think of this but geographers think of it all the time. it exploits space. understand things that are happening all the time. i now have my limiting intensity. i can put that for each of my boxes but i also have my ocean

temperatures. now i have the two pieces i need. when i put those two together, i get this beautiful plot. here's my ocean temperatures, here's how you can get in that slope represents the sensitivity of hurricane intensity to ocean warmth. it turns out that is exactly were close to 8 meters. second. to translate that, that is about 16 miles per hour for every degrees celsius of warming or 2 degrees fahrenheit of warming. that's how much stronger hurricanes we can expect to get.

that's never been worked out before and it is a fundamental component of how the atmosphere works. why is this important? that's 8 meters. second, plus or minus one. why is that important? it turns out they're getting stronger. we can see that every year we can the storms by their intensity. we can see that's not changing much. these upper quantities are going up and the going up about a meter. second. decade. this is where it starts to get interesting. the loss of 5%. second. here is your windspeed and

here's your economic damage with billions of dollars. that indicates how much more damage we can expect for every increase in windspeed. this is important. and maps onto the next aggregation of the next 20, 30, 50 years more of hurricanes. we will see this kind of change. forget about the fact that were maybe going to have more stuff in the way. this is completely independent , based on the theory of how things operate. it's extremely important. so i'm about halfway. just a quick summary, you can understand what hurricanes might be like in the future by combining the theory with the data. the theory in-and-out, how hurricanes are heat engines, it's likely the strongest hurricanes will get stronger.

degree of ocean warming. this amounts to about 1 meter. second at the current decade which is about a 5% increase in losses. decade independent of how much we are exposing. for exposing more of course you will get more than that. keeping exposure constant, that is the increase. of course you're going to say jim, there's lots of other factors. one factor that affects the sensitivity, if you put those in our model, they're not very strong. now there could be something i'm missing, as a scientist you always reserve the right to be wrong and to be found wrong, that's just part of our job, but because as part of our job, we think about this all times. okay let me talk about

tornadoes and then will stop and you can ask questions. maybe tornadoes are somewhat mysterious to you but as a scientist to me, it's the same idea. that's this idea that the atmosphere produces the ways, the winds blow faster in tornadoes than hurricanes on average. there's been a lot of talk about what will happen with tornadoes. if you look at the annual accounts, the number of ef one or higher tornadoes, we rate these tornadoes and when that scale starts at zero, it's

about 80 miles per hour we don't really see any trend in the numbers of storms. this absence of trend doesn't imply that the climate is stationary but it often stifles the discussion. what we find is the number of days with tornadoes provides additional information. unlike hurricanes we don't have any theory to hang our hats on with regard to what tornadoes might be like in the future. we do understand the data and there's a lot more tornadoes and hurricanes so we have something to go on. unfortunately we become much better at observing tornadoes. if you look at a long record of tornadoes, there's generally an increase in the

numbers and that is because we are probably able to communicate what we see and there's more people paying attention paired we have a population bias. this is the number of tornado reports so just how many tornadoes do you see within ten square kilometers as a function of distance. you see 1.4 tornadoes to less than one, about .8 away from the city.

people say the cities are where they can get records into record book. that's what were seeing. there are a couple of things that are very interesting. snakes that have been alerted.

it's flattening out. we don't see an urban effect versus a roll effect today. it's not the cities that are causing the hurricane. i do spend a lot of time making nice plots. that's how i put the pieces together. i think if i did it this way i can see that and i don't see that then i can devise this right here is your number of tornadoes over time since about in 1954 and this is only the stronger tornadoes. you can see a bounce around from year-to-year.

2011 was a big year. we are seeing fewer tornado days. the same number of tornadoes but they are occurring on fewer days. she was very instrumental in trying to ge make these plots. we are seeing fewer days with tornadoes and that's the key. suppose i count the number of days. i told you i would have lots of graphs.

there were at least four tornadoes, about 35 days in 1954 where there were tornadoes reported. that bounces around, but as you get to a larger and to eight and 16 amenta 32, you start to see this upward trend. what are we seeing folks. we are seeing that although the number of tornadoes is less, the days in which there are big outbreaks are increasing. it's like the atmosphere saves itself for a big day, to put it in those terms. but, that's what were seeing. we can do this in a slightly different way, we can talk about probability.

we are just getting these bigger outbreaks. what's happening. that's where my head is when i wake up. why is it happening? that is so i can do this a slightly different way and i can think about this in a percentage of change. no matter which way you do it, it's not the number of vents but it's a big events. it's kind of like the hurricane problem. the stronger storms are getting stronger, no doubt about that. we are nothing more hurricanes, but the stronger ones are getting stronger. were nothing more tornadoes but they're coming in bigger bunches. all of these graphs are

showing these kinds of things. there is a large-scale hypothesis that was put out. as soon as i tweeted, i got a lot of folks tweeting back. the atmosphere is becoming more efficient. when you think about the stronger storm getting stronger, the time that it takes for hurricanes to intensify isn't going to change. have to come across and move across the ocean, they only have so much time to get strong. that's not going to change. the oceans are getting wider, at least on the scale of humans so they're going to have the same amount of time so they're getting stronger.

i like this idea of intensity. the atmosphere is more efficient. tornadoes start from the ground up. i think the water start is probably different but the tornadoes were talking about start from the ground up. it looks like they come from the cloud because the condensation comes from the cloud. it appears because that's what we see.

the spin actually starts at the ground. it's spinning up here but on a much larger scale and it kind of gets together. we can have another lecture but here i'm talking maybe the atmosphere is just getting better over a larger area. let's look at a particular day. this is just one day in 2008 and there were a number of tornadoes but they occurred in two different regions. what i do is i think about this is a cluster of tornadoes. i just draw a box and i'd draw where they've occurred. what i think is happening, my hypothesis was that these things are getting bigger. there's more of them so these areas are getting larger.

i just put this red dot, this represents the center of the tornado. it's closest to the center. that is the middle tornado. we all know about the median or the means credits closer to the median. it's the tornado that represents closest to the center. to get rid of all tornadoes. okay. what's important is that i was wrong about the hypothesis. were not seeing more clusters. that's pretty flat. it's not really significant.

maybe there are a few more clusters. the total area of clusters is flat. i was wrong about this large-scale hypothesis. what's happening is where getting more tornadoes, they're just getting to more climate that's favorable to formation but then i can look at the density and say how many tornadoes. cluster.

it's not a large scale, it's probably the local scale. when you think about this increased low-level moisture as long as we have some kind of cap. speculation, i don't have the answer, seeming in about half a year i will.

we just talked about the numbers. area. the problem with the intensity of tornadoes is that we don't really measure how fast the tornadoes are rotating. they are rotating so fast that if you have a wind instrument you will probably see it be destroyed. those are very few. you're not going to get too many intercepts like that. we thought we've got to be able to back off the intensity from the scale. in count the number of tornadoe tornadoes.

let me tell you of the stronger ones are getting stronger. turns out, here is an example of a tornado path. this is the damage path adheres oklahoma, here's oklahoma city. there's a couple things you can see about that path. first of all, we can think about the area, how much area did that tornado cover. we can characterize the area by how long it is and how wide it is. length and wit turn out to be two ways to describe path of a tornado. we look at the different tornadoes, these are stronger and stronger and this is the number of tornadoes by that category.

here is the area in square kilometers. a tornado doesn't come out of the sky, it comes out very smal small. you can get up to a hundred hundred and 20, hundred and 50 meters purse second. it travels over longer distances so the path of the area is different. i know i can work out some kind of energy in that storm. this is tornado energy over time. here we can see the approximate energy going way up. not only are they becoming bigger bunches, they are

getting stronger, longer and more energetic. that is really, really interesting but nobody has any answers yet. i did this, just for florida we are seeing longer paths in florida. i decided to do a little bit differently. this is late. over time you can see they are getting longer.

they can be misleading. when people say we haven't her seen a hurricane forever, not really. they say we used to see just as many as before, or we see more now, probably not. these are single metrics. how often and how strong are the two components. take any storm. you think about how frequently they occur and how strong they are when they occur. by analyzing them we can get this broad understanding of understanding. whether it's hurricanes or tornadoes. with hurricanes and typhoons, a fingerprint appears to be fewer but stronger. this is the take-home graph to

try to understand what global warming might be doing to hurricanes. we are kind of thinking about activity going on, there's el niño events, there's all kinds of climate variation going on. we may actually see fewer hurricanes, but when we do get them they are strong. the separation in terms of frequency and intensity is may be what climate change is doing. [applause] now i'll open it up to questions.

[inaudible] [inaudible] it crossed several states,

illinois and indiana. the ef scale was not invented then, it was invented by theodore from the university of chicago in the 1970s and wasn't implemented by the national weather service until the early '80s. i think what they are able to do with tornadoes like that is look at photographic evidence and say based on those photographs, the targets that were hit in did indicated ef for damage. i believe it's in the record book is an ef five but i'm not positive about that. that's a great question. [inaudible]

[inaudible] >> that is a great question. it is a question that i think about quite a bit. it is the question that if i'm wrong about the data, if i'm mistaken and if i'm assuming

it's this way and are not, then of course my conclusions are going to come crumbling down. one of the things we do is we go out and try to survey. that's one thing. when we build the models, we take into account things like the ef scale that was implemented this year. as a statistician, i can put that in my model and i can control for it. control not in a laboratory sense but in a statistical sense. i am able to capture quite a bit of this stuff. there's all kind of stuff that could be there. a lot of the stuff tends to be random variations. it's not systematic.

if there's anything systematic, my models will catch it. that's the nature of statistical models. they will catch it and leave the random variation as the residual. but, i could interpret nonrando nonrandom, i can interpret signal in the wrong way, but i tried to work with folks that know a lot about the data set and i'm aware of a lot of the changes that have occurred over time but those are legitimate concerns. >> so people had talked to me before, the folks at the prediction center said does data have this population bias. they said have you ever quantified it. by doing the snake plot, i quantify it. and, i can quantify it in such a way that for any region i

can tell you when it's unlikely to have any population bias. at least population bias in the sense of gradient. i can do distance. i put the roadway network in there and i said okay, does the roadway give you better coverage. i can play those what if games with the information i have. that's why, i think getting back to this idea about theory and data, if you have theory you can start doing things a lot stronger. if you're just playing with dat data, those are the caveats, buyer beware. two quick questions. who are your partners in researching those tornadoes and hurricanes, and then

second to that, in this area, one of the things is to sort of show them increasing in the area. you see them using it. >> that's a great question. it's really not simple to answer. first of all, about the people that i work with, as i mentioned carrie emanuel, he's one of the guys i can lean on. he is at the proper distance from me. were not friends, but were good colleagues. i pay attention to his work and he pays attention to mine. they've drilled down in

coastal regions and looked for deposits and historic hurricane events. [inaudible]

i think the problem with the tornado is they tend to underestimate the risk. tornadoes are called than people in other words, if you look at insurance policies in oklahoma you are -- i don't know about policy but i know your risk is probably about your house being hit by a tornado is about one in a thousand years. that's what they tell me. i believe is closer to one in 500. it's about half. they are underestimating the risk of potatoes in many places in the us. concerning the hurricane problem and the coastal leaks the insurance companies got it wrong. i was part of that discussion. they came to us back in the mid- 2000 and said what will happen,

2004, 2005, in the big seasons they said me and a group of us and said what will happen. we have seen this and they said basically worsening more storms in the atlantic and the atlantic is warming up and they took that idea that the atlantic is getting warmer and transferred it to the coast. we try to stop them and the correlation between postal activities and atlantic activity is weak. we have big seasons without any hurricanes and that is the piece that they missed. it was in their favor to raise the rates and they had the science to back them up. the science on the coast is never there -- the storms are getting more frequent. what you do see is if you look at losses along the coast and look at historical losses, insured losses from texas to maine the number of losses is not going up over time but given

a loss event magnitude and how much loss depends sensitively on ocean temperature. the warmer it is the more losses you get. controlling for inflation -- the stronger storms are produced by the warmer temperatures and that is not in doubt. it shows up in the but whether we will see more loss events, i don't buy it. [inaudible]

i think you're onto something. i know i want this in terms but it's not proper but the atmosphere does have this psychological constraint almost. if there will be stronger and more and that occurs with things like rain what is going on here is the system is being fueled and there's these cancer forces that keep things in check but when they go they go hard. again, all i can offer is a few vague terms and maybe borrow from ecology at a certain point.

it is thinking that way to unify climate changes in the science and maybe it takes some biologists and ecologists to help us out and think through this problem. they absolutely love that idea. [inaudible] i haven't studied that problem but i thank you could do similar diagnostics. i think the metrics -- i'd love to give another talk about that because i have done that and i've set up the phase space of frequency and tenancy and mapped that in the climate change and it is this notion of efficiency that maps onto climate change and it's exactly that.

it would be fun to do it for a bunch of things like floods and drought. [inaudible] [inaudible] >> yeah, i don't know the answer to that question. i do study them to the extent that they might impact the storming is that i think about. you have heard the term of arctic implication maybe and the idea that it will get warmer in the arctic and faster than it will and lower latitudes. this application fees into the idea that you will have fewer

desk to get a tornado unit two things, wind shear which is the opposite of the hurricane because the hurricane will get torn apart by windshear but thunderstorm needs to have a rotation in that rotation is by the shearing wins. those shearing winds are caused by the jet stream. you will get a weaker jet stream so that would argue that would see fewer tornadoes but what you're seeing and you need moisture, too. the moisture is going up and the jet stream on average is getting weaker but when it does come down now you have more more moisture. in a hand waiting way you can kind of explain my results. i tried to connect them but i was shot down. [inaudible]

[inaudible] [inaudible]

>> it is not clear if that is how the insurance companies work on it and they are highly regulated -- at least the primary ass well, they are. that's why they lobby. it's largely at the state level. i really don't have expertise so i could say something stupid quickly. [inaudible] >> well, i do say you are paying ten times more in florida than you do in maine. i would say you are ten times more likely to get a category three, category three hurricane in florida and you are in maine. so, back of the envelope says

your rates are commensurate with the relative rates between the two are commensurate with the relative risk -- [inaudible] >> but your insurance policy is wind. i'm not talking about surge. [inaudible] >> those are great points but i don't have much expertise. [inaudible]

[inaudible] >> that is a great points. there are a lot of local -- i did have a figure, this might be right here that showed all the tornadoes in the last 30 years in this area and it's not showing up -- [inaudible] >> you do have convergence on here because of the shape of the

coastline so the area that we call or labeled capes hell is a convergence zone -- it is possible that you will get events in that region more often because you get a thunderstorm there more often. i don't think it's or tomato thing but you'll have more thunderstorms. there are a lot of local influences and given the fact that this whole area gets the same number of thunderstorms and areas, for example, that had smoother trade and have more tornadoes and more rough terrain or trees. when you cut the trees down, the airflows in a smoother way and can produce or tomato, on average.

[applause] >> senator chris murphy is spending this congressional break walking across connecticut. he started sunday and is walking about 25 miles a day in 2010 talking to residents along the way. this morning he iran into a group of students who apparently set out to find him. all these kids who didn't know each other happen to find me at the same time. impromptu town hall, senator murphy treated. 11 miles into his walk this morning he had lunch with his senate interns. eleven more miles to go before this evening's town hall in newtown connecticut in the senator and his and hundred and his walk tomorrow in danbury. the tv is in prime time tonight with military history, retired admiral for the history of navies around the world in the importance of seapower. professor jenner king on world

war i the american soldier experience. james wright discusses his book and during vietnam and andrew carol looks at world war i to the eyes of general john pershing, the commander in europe and my fellow soldiers. book tv in prime time all this week at c-span2. >> this week and on book tv. saturday at 10:00 a.m. eastern we are live at the mississippi book festival with featured offers including mark about it on his book. walter starr, author of standing, lincoln's war secretary and alvin on his book a man and his presidents. the political odyssey of william f buckley junior. sunday and i'm p.m. eastern, we have a guest on "after words". >> trolling is about sweeping