Heat Waves (4) A Climate Case Study:

By: Dr. Ricky Rood , 6:26 AM GMT on July 19, 2011

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Heat Waves (4) A Climate Case Study:

In the last article I wrote that the extreme events of 2011 were providing us with the opportunity to think about climate and how to cope with a warming world. The U.S. is experiencing an extreme heat event this week (Masters @ WU). This heat wave is the consequence of a strong, stationary high pressure system over the central U.S., and it will move to the east over the next few days. Back on July 14th The Capital Weather Gang did a nice write up on the forecast of the heat wave. At the end of this blog are links to my previous blogs on heat waves and human health.

When thinking about weather, climate, and extreme events an important idea is “persistence.” For example, a heat wave occurs when there are persistent high temperatures. Persistent weather patterns occur when high and low pressure systems get large and stuck; that is, they don’t move. In the Figure below, you need to imagine North America and the United States. There is a high pressure center over the proverbial Heartland. With blue arrows I have drawn the flow of air around the high pressure system, and in this case moist air. There is moisture coming from the Gulf of Mexico and, in fact on the date when this was drawn, from the Pacific. This is common in the summer to see both the Gulf of Mexico and Pacific as sources of continental moisture.



Figure 1: Schematic of a high pressure system over the central United States in July. While generic, this is drawn to represent some of the specifics of 2011. The green-shaded area is where there have been floods in 2011. The brown-shaded area represents sustained drought in the southern part of the nation.

At the center of this high pressure system there is a suppression of rain, because the air is moving downward. This sets up a situation where the surface heats from the Sun’s energy. There is not much mixing and cooling, because of the suppression of the upward motion that produces rain. Hence, if this high pressure system gets stuck, then there is persistent heat. This is a classic summer heat wave.

Let’s think about it some more. There is lot of moisture being drawn around the edge of the high pressure system, and this moisture contributes to the discomfort of people. People – just a short aside about people: if we think about heat and health, then we are concerned about people’s ability to cool themselves. It is more difficult to cool people when it is humid because sweat does not evaporate. Suppose that in addition to this moisture, there is a region where the ground is soaked with water from flooding. Then on top of already moist air coming from the Gulf, there is local evaporation into the air being warmed by the Sun. If on the interior of the high, where the rain is suppressed, there is hot, wet air, then it becomes dangerous heat.

It’s not easy to derive a number that describes dangerous heat. But in much of the eastern U.S. a number that somehow combines temperature and humidity is useful. Meteorologists often use the heat index. It’s the summer time version of “it’s 98 degrees, but it feels like 105.” For moist climates, the heat index is one version of the “it feels like” temperature. Jeff Masters tells me that in Newton, Iowa yesterday, July 17, 2011, the heat index was 126 degrees F. (see here, and 131 F in Knoxville, Iowa on July 18)

Another measure of heat and humidity is the dew point; that is, the temperature at which dew forms, and effectively limits the nighttime low. The dew points in Iowa, South Dakota, Minnesota, and Wisconsin are currently very high and setting records. Here is a map of dew point for July 19, 2011.



Figure 2: Exceptionally high dew points centered on Iowa.


Now if I was a public health official, and I was trying to understand how a warming planet might impact my life, then here is how I would think about it. First, the Gulf of Mexico and the Pacific are going to be warmer, and hence, there will be more humid air. This will mean, with regard to human health for the central U.S., heat waves will become more dangerous, without necessarily becoming hotter. It is also reasonable to expect heat waves will become more frequent and last longer, because those persistent, stuck high pressure systems are, in part, forced by the higher sea surface temperatures. If I am a public health official here is my algorithm – heat waves are already important to my life, and they are likely to get more dangerous, more frequent, and of longer duration. But by how much? Do I need to know by how much before I decide on a plan for action?

If I think about the air being more humid, then I might expect to see trends in the heat index. I might expect to see trends in dew points, and trends in the nighttime minimum temperatures getting higher. (That’s where a greenhouse effect really matters.) I worry about persistent heat, warm nights, and the inability of people and buildings to cool themselves. I worry about their being dangerous heat in places where people and emergency rooms are not used to dangerous heat – not acclimated to heat – not looking for heat-related illness.

Let’s go back to the figure. Rain is suppressed in the middle of the high pressure system, but around the edge of the high pressure system it will rain; there will be storms. (see Figure 3 at the end) The air around the edge of high is warm and very wet. Wet air is energetic air, and it is reasonable to expect local severe storms. (See Severe Storm on Lake Michigan) And if the high pressure is persistent, stuck, then days of extreme weather are possible. If this pattern sets up, then there is increased likelihood of flooding. If I am that public health official, then I am alerted to the possibility of more extreme weather and the dangers thereof. But, again, can the increase of extreme weather be quantified? Do I need to quantify it before I decide on a plan of action?

Still with the figure - what about that region of extended drought and the heat from the high pressure system? Dehydration becomes a more important issue. As a public health official, I start to see the relation of the heat event to other aspects of the weather, the climate. I see the relation to drought. I see the flood, and it’s relation to the winter snow pack and spring rains.

So what I have presented here is to look at the local mechanisms of the weather – what are the basic underlying physics responsible for hot and cold, wet and dry – for moist air? If I stick to these basic physics, and let the climate model frame the more complex regional and global picture, what can I say about the future? Do I have to have a formal prediction to take action? Here in 2011, I see drought and flood and hot weather and warm oceans that interact together to make a period of sustained, dangerous heat. It does not have to “set a record” to convey the reality of the warming earth. It tells me the type of event that is likely to come more often, of longer duration, and of, perhaps, of greater intensity. If I am a public health planner, then I can know this with some certainty. The question becomes, how do I use that information in my planning?

r



Figure 3: Radar loop showing precipitation around the edge of the large high pressure system in the middle of the continent. July 19, 2011.

Previous Blogs on Heat Waves

Hot in Denver: Heat Waves (1)

Heat Waves (2): Heat and Humans

Heat Waves (3): Role of Global Warming




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714, so please explain why the first 3 months of this year the Global Temperature was below normal? UAH records show it quite clearly.
Member Since: June 12, 2005 Posts: 6 Comments: 8185
1979--not very long, geologically speaking.



Member Since: August 17, 2010 Posts: 1 Comments: 730
Speaking of anti-science, cherry picking, lack of conflict of interest policy, and gerneral dishonesty!


Greenpeace and the IPCC – The Edenhofer Excuse


"It has been a recurring pattern that the most dramatic of conclusions arrived by the IPCC, are shown to arise from unsubstantiated or exaggerated claims in literature put out by environmental pressure groups. The latest addition to the list is the Greenpeace-generated factoid that ‘80% of the world’s energy demand could be met by renewable sources’ which found its way onto the IPCC pedestal."

Member Since: June 12, 2005 Posts: 6 Comments: 8185
Quoting JBastardi:


Figures lie and liars figure.

Was the recent heatwave really "unprecedented"?

Link

That header graphic may be one of the funniest things I've ever seen. Cherry-picking temperature data starting with 1998 as they've done is like going to the beach at high-tide, observing the water levels for six hours, then proclaiming that the ocean is draining. Silly denialists...

And it's not just the graphic that's laughable; the whole premise upon which the text is based is anti-science comedy at it's best. Apparently the writer isn't aware that "all-time record high heat" is identical to "unprecedented heat". And when he starts comparing numbers, I've really got to chuckle. Do you think he knows that 48 all-time record high temps were set or tied Friday and Saturday alone? Think he knows that daily record highs have outnumbered daily record lows across the U.S. 3,573 to 120 over the past week alone, a ratio of nearly 30 to 1? Think he knows that record daily highs for the year outnumber record daily lows by 15,327 to 6,255, or 2.45 to 1?

As always, a spate of record temps in either direction doesn't prove or disprove GW. But in a neutral world, one would rightly expect record highs and record lows to roughly balance out. The fact that each passing decade sees an increasingly disproportionate large number of record highs, then, is very telling.
Member Since: November 8, 2009 Posts: 4 Comments: 13472
Quoting nymore:
So that is why Bill Gates was gonna use barges and giant pumps for his idea to cool the surface of the ocean in front of hurricanes you should call him and tell him nature will do that no need for pumps and the engineers he hired are idiots for not knowing this


I can't tell you what Bill Gates thinks. But I can tell you his idea does not produce electricity nor does it work if no waves are present. Ever see how calm the seas are two or three days prior to a storms arrival? His idea can not regulate the SST's either.
Member Since: January 2, 2006 Posts: 127 Comments: 20396
So that is why Bill Gates was gonna use barges and giant pumps for his idea to cool the surface of the ocean in front of hurricanes you should call him and tell him nature will do that no need for pumps and the engineers he hired are idiots for not knowing this
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
you mean the video showing the velocity of the water pushing it up 6 inches now lets do this in the ocean taking into account density difference, temperature difference and velocity of moving water 500 feet vertically, pipe roughness and bends causing friction and lets see how it works oh that's right it doesn't now I am done


Dude the water was flowing 20 times slower in that video than it does in the gulfstream. Depth is a non issue here because the pressure in the pipe is the same as the pressure outside the pipe. It is the kinetic energy at the tunnel inlet which forces the water up the pipe. Comprende?
Member Since: January 2, 2006 Posts: 127 Comments: 20396
you mean the video showing the velocity of the water pushing it up 6 inches now lets do this in the ocean taking into account density difference, temperature difference and velocity of moving water 500 feet vertically, pipe roughness and bends causing friction and lets see how it works oh that's right it doesn't now I am done ps the died water being warmer than the river water would also help
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
It doesn't oh by the way I gave you the equation for f1 1.5 hours ago and you could not figure that out either your idea is impossible


Then explain the video Mr. smarty pants!
Member Since: January 2, 2006 Posts: 127 Comments: 20396
It doesn't oh by the way I gave you the equation for f1 1.5 hours ago and you could not figure that out either your idea is impossible
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
really- do you have a well for water


What does that matter? What is your point?
Member Since: January 2, 2006 Posts: 127 Comments: 20396
really- do you have a well for water
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
oh my god what


Correct head pressure is a function of altitude. Look it up sometime.
Member Since: January 2, 2006 Posts: 127 Comments: 20396
Quoting JBastardi:


Figures lie and liars figure.

Was the recent heatwave really "unprecedented"?

Link


So how hot would it be now if that heat hasn't been going into the arctic to melt more ice?
Member Since: January 2, 2006 Posts: 127 Comments: 20396
are you asking me a question JB
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
how do you know what the head pressure is at f1 and f2


Height or altitude.
Member Since: January 2, 2006 Posts: 127 Comments: 20396
Quoting nymore:
NEAPOLITAN- OK that was a nice speech but I am still waiting for the sources when you have asked me for my sources I have provided them not from denialist sites but from reputable sources even though you accused me of taking them from propaganda sites before I posted the real sources.


Figures lie and liars figure.

Was the recent heatwave really "unprecedented"?

Link
Member Since: July 5, 2011 Posts: 0 Comments: 403
how do you know what the head pressure is at f1 and f2
Member Since: July 6, 2011 Posts: 0 Comments: 2255
F1 is at tunnel inlet. F2 is at tunnel outlet. The difference in those forces is what creates the flow.
Member Since: January 2, 2006 Posts: 127 Comments: 20396
so what formula to calculate f1 and f2
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
yours is for a closed system ie hydraulics mine is for an open system. what formula did you use to calculate f1 and f2 which don't matter in an open system anyway


Negative it can be for both.
Member Since: January 2, 2006 Posts: 127 Comments: 20396
yours is for a closed system ie hydraulics mine is for an open system. what formula did you use to calculate f1 and f2 which don't matter in an open system anyway
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
yes I have seen it h=z(x)plus p(x)plus P(x)2 over (pg) (-2g) Do you understand this formula? This is one reason why it will not work.


This is the formula F1>F2.Kindly explain yours?
Member Since: January 2, 2006 Posts: 127 Comments: 20396
yes I have seen it h=z(x)plus p(x)plus P(x)2 over (pg)plus (2g) Do you understand this formula? This is one reason why it will not work.
Member Since: July 6, 2011 Posts: 0 Comments: 2255
The fact water flows through the tunnel makes it a open system. Comment 686 I had wrong it is a open system.
Member Since: January 2, 2006 Posts: 127 Comments: 20396
Quoting nymore:
do you understand what closed system is? Just because it is underwater does not make it a closed system


I know perfectly well what a closed system is. Being underwater is what makes it work. Again have you seen the video?
Member Since: January 2, 2006 Posts: 127 Comments: 20396
do you understand what closed system is? Just because it is underwater does not make it a closed system
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
so you reuse the water


Eventually it is reused but it may take a thousand years.Depending on how many are built. Have you seen the video?
Member Since: January 2, 2006 Posts: 127 Comments: 20396
so you reuse the water
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
Cyclone the diagrams you posted are for a closed system such as hydraulics but since your system is open they are useless


It is a closed system because it is all under water and has a head pressure at the surface as well as at the bottom. Energy is also conserved within the closed system.Have you seen the video proving the concept?
Member Since: January 2, 2006 Posts: 127 Comments: 20396
Cyclone the diagrams you posted are for a closed system such as hydraulics but since your system is open they are useless
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Neo I like how you changed your post 642 and never admitted you were caught making facts up AGAIN. You have been caught posting so many false facts I am surprised you keep coming back
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting JupiterKen:
'buster,

You did not provide any evidnece of anyone (a real person) that agrees with you that your tunnels can work. You have farmed your idea at many, many websites and no one agrees with you. Why is that? Ya think, maybe, it's because it won't work?


Have you seen the idea working in the video? F1>F2 proves it works as seen in the video!
Member Since: January 2, 2006 Posts: 127 Comments: 20396
Thank you everyone for coming drive safe and please tip the staff before you leave
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting nymore:
Ossqss- Neo is a computer programmer, writer and blogger he has stated this himself. He may feel more superior by calling himself a ( computer ) scientist but anybody can we used to call our trash man a garbologist.


haha

I don't condone this type of debate but that was pretty funny

garbologist

See this is why I blog

Member Since: August 17, 2010 Posts: 1 Comments: 730
FUN FACTS about CARBON DIOXIDE

* Of the 186 billion tons of carbon from CO2 that enter earth's atmosphere each year from all sources, only 6 billion tons are from human activity. Approximately 90 billion tons come from biologic activity in earth's oceans and another 90 billion tons from such sources as volcanoes and decaying land plants.


Quoting Neapolitan:

Not sure where your "data" is coming from. China alone pumps more than billion tonnes of CO2 into the atmosphere from the burning of fossil fuels each year. And since a basic and well-known fact is wildly misstated in your very first sentence, the rest of the comment simply can't be trusted.

(Seriously, those Geocraft graphs you've posted have been debunked so many times that they belong in the main exhibit room at the Denialist Hall of Fame. ;-) In lieu of them, can you please post some charts and graphs drawing on actual scientific data?)


*Edited to suit Neapolitan Fact, a seperate conclusion of facts based on China's willingness to share truthful information of their industrial byproducts with Neapolitan, a blogger and scientist, and not with larger unilateral global environmental agencies:

FUN FACTS about CARBON DIOXIDE

* Of the 186 billion tons of carbon from CO2 that enter earth's atmosphere each year from all sources, discounting Dr. Neapolitan's claim that "China alone pumps more than billion tonnes of CO2 into the atmosphere from the burning of fossil fuels each year", what ever that factual statement means is up to the Jeopardy judges, only 6 billion tons are from human activity. Approximately 90 billion tons come from biologic activity in earth's oceans and another 90 billion tons from such sources as volcanoes and decaying land plants.

* At 380 parts per million CO2 is a minor constituent of earth's atmosphere-- less than 4/100ths of 1% of all gases present.


NOTE: Carbon Dioxide is such a small component of Earth's atmosphere (368 ppmv) that the "slice" it represents in this chart is really only a "line" about 1/2 as thick as the line shown.

Compared to former geologic times, earth's current atmosphere is CO2- impoverished.


Late Carboniferous to Early Permian time (315 mya -- 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period ).


* CO2 is odorless, colorless, and tasteless. Plants absorb CO2 and emit oxygen as a waste product. Humans and animals breathe oxygen and emit CO2 as a waste product. Carbon dioxide is a nutrient, not a pollutant, and all life-- plants and animals alike-- benefit from more of it. All life on earth is carbon-based and CO2 is an essential ingredient. When plant-growers want to stimulate plant growth, they introduce more carbon dioxide.

* CO2 that goes into the atmosphere does not stay there but is continually recycled by terrestrial plant life and earth's oceans-- the great retirement home for most terrestrial carbon dioxide.



If we are in a global warming crisis today, even the most aggressive and costly proposals for limiting industrial carbon dioxide emissions would have a negligible effect on global climate!



Member Since: August 17, 2010 Posts: 1 Comments: 730
Neapolitan, at least give me credit for not denying the earth is warming.

Forgive me for be a skeptic as to the causes and even the consequences.

I'm here to learn, as well as throw my own two cents around.

Member Since: August 17, 2010 Posts: 1 Comments: 730
anyone want to tell me what china's total CO2 emissions are since 1979?

maybe I'm having a hard time fidning it because I can't read mandarin chinese.
Member Since: August 17, 2010 Posts: 1 Comments: 730
Quoting Neapolitan:

Of course I've provided "proof" of my claims. In fact, unless I stated otherwise, every single thing I've ever posted here that I stated as scientific fact was, indeed, scientific fact (and it came from actual scientific sources, and not, say, from a site filled with the irrational blather of a non-degreed one-time small-market TV weather reader claiming expert knowledge). Now, I could easily waste many, many hours going back and again citing every scientific fact I've ever repeated here, but I think I'll do that when someone new comes aboard. Everyone here has had ample opportunity to see my references, so I feel no need to waste my energy repeating things I've stated before many, many times.

Ho-hum...


If you are referring to what I posted earlier..I gave the online paper's references and works cited. Many are from NASA, NOAA, MIT and other acredited entities and professionals of climate science and geology.



Member Since: August 17, 2010 Posts: 1 Comments: 730
NEAPOLITAN- OK that was a nice speech but I am still waiting for the sources when you have asked me for my sources I have provided them not from denialist sites but from reputable sources even though you accused me of taking them from propaganda sites before I posted the real sources.
Member Since: July 6, 2011 Posts: 0 Comments: 2255
Quoting Neapolitan:

Again with the name calling? I'm sorry that you and a few others here feel the need to resort to that when frustrated; I wish that were not the case. Now, you made a demonstrably false statement. I challenged that statement on scientific grounds. You stated that you have a right to pick and choose. I responded that your're not entitled to your own facts. It seems to me that if you find that "insulting", perhaps it's only because you recognize the truth in what I say. (Though to be honest, I didn't insult you, per se; just the incorrect data you posted.)

To answer your first question, yes, I am indeed a scientist.


well, what name did I call you?

none.

I am not an author of science.

There are no rules of blogging that say one has to be a scientist or an author to form a conclusion.

I would like to believe, that true scientists don't sound like journalists and politicans, your many references and quips of news organizations you don't favor make me question the science you endorse.

Are you published? And, though you might think otherwise, I don't judge you to be wrong or unqualified in the fields of science. I myself hold no degrees in science nor am I published, but that doesn't mean, as a science hobbist, I don't understand the scientific process.

I'd like to read some of your published research if you are indeed a scientist by profession.

Forgive me if I insinuate your comments as politically driven and main stream with a touch of sarcasm and heavy doses of what I feel resembles rhetoric unfitting of educated scientists.

I enjoy the debates and look forward to more evidence man is responsible for whatever the disaster is that everyone is afraid of; that too is unclear.


Member Since: August 17, 2010 Posts: 1 Comments: 730
Quoting Ossqss:


Hey, get in line! He still has not provided the proof for his claims in 549 I had asked for, let alone the hundreds of other opinionated claims :)

I just glanced back and find many amazing statements.

I will only comment on a few.

Food costs are directly correlated to energy costs. Farming, fertilizer production, pesticides, processing, packaging, transportation, storage, refrigeration etc, are all directly impacted by the cost of energy needed to make stuff mysteriously appear in your grocery isles.

Barely making it means a high speed internet connection, laptop, and smartphone now days I guess.

How exposure to indoctrination can change peoples interpretation of things in the real world ......

Must be some new standard with respect to calling yourself a scientist now days too. What are those standards anyhow?

Of course I've provided "proof" of my claims. In fact, unless I stated otherwise, every single thing I've ever posted here that I stated as scientific fact was, indeed, scientific fact (and it came from actual scientific sources, and not, say, from a site filled with the irrational blather of a non-degreed one-time small-market TV weather reader claiming expert knowledge). Now, I could easily waste many, many hours going back and again citing every scientific fact I've ever repeated here, but I think I'll do that when someone new comes aboard. Everyone here has had ample opportunity to see my references, so I feel no need to waste my energy repeating things I've stated before many, many times.

Ho-hum...
Member Since: November 8, 2009 Posts: 4 Comments: 13472
'buster,

You did not provide any evidnece of anyone (a real person) that agrees with you that your tunnels can work. You have farmed your idea at many, many websites and no one agrees with you. Why is that? Ya think, maybe, it's because it won't work?
Member Since: Posts: Comments:
Quoting nymore:
Neapolitan I am still waiting for your sources to the facts you post.


Hey, get in line! He still has not provided the proof for his claims in 549 I had asked for, let alone the hundreds of other opinionated claims :)

I just glanced back and find many amazing statements.

I will only comment on a few.

Food costs are directly correlated to energy costs. Farming, fertilizer production, pesticides, processing, packaging, transportation, storage, refrigeration etc, are all directly impacted by the cost of energy needed to make stuff mysteriously appear in your grocery isles.

Barely making it means a high speed internet connection, laptop, and smartphone now days I guess.

How exposure to indoctrination can change peoples interpretation of things in the real world ......

Must be some new standard with respect to calling yourself a scientist now days too. What are those standards anyhow?
Member Since: June 12, 2005 Posts: 6 Comments: 8185
Neapolitan I am still waiting for your sources to the facts you post.
Member Since: July 6, 2011 Posts: 0 Comments: 2255

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About RickyRood

I'm a professor at U Michigan and lead a course on climate change problem solving. These articles often come from and contribute to the course.

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