climate change

Thanks to a lot of work done by Dr. Harold Brooks and collaborators, the U.S. climate change science programs report included information on severe convective storms. There was enough in the report to show the valuable work done by Brooks and collaborators. What was missing was what occurred this year with regard to severe storms:
A. Multiple EF5 tornados, and
B. Extreme Flooding brought about by severe storms

One interesting point is that the reanalysis data doesnt show changes in severe storm environments concurrent with changes in tornado reports. Either the problem truly requires a mesoscale depiction to identify the environment [reanalysis is too coarse] or the parameter relationships do not describe the potential for severe storms. This latter part means that more variables need to be considered or at least scaled, or a distributions approach needs to be taken.

While models are incapable of producing the heavy rainfall associated with severe convective storms, I have not seen a method to estimate the potential heavy rainfall associated with a severe storm environment. Obviously this would be of great interest since the US is especially vulnerable to flood (more agricultural production for food, fuel, and livestock) and drought more by economic considerations rather than true vulnerability (poor placement of cities, homes, overdevelopment in areas prone to flood). The Floods of 08 (June) and 93 (July) redefined record flooding.

20 river crest records broken in 93 were in the st louis area. Iowa set a number of records, and the recent levee breaks in and around St Louis may make breaking records tough, but no doubt this a record year for flooding.

Policy changes are needed to keep people and property sustainable. We are at more risk. Not because of increased weather, but because our society is more dependent on the status quo. More development means more risk. More risk leads to more money being spent to keep current. fewer people can handle that risk because they dont have the money. A lot of people take the chance. And a lot of people lost this year (some may have been misled into not getting flood insurance). I am thinking now that climate change may have more impact on HOW we do business, HOW we treat our planet and each other, than on actually changing the climate.

No doubt the climate is changing. The question is: how much will we?

Then and now

I was watching the show Greensberg (so named after the tornado wiped Greensberg KS off the map). They had a unique opportunity to rebuild from scratch ... truly relearning what they needed to do to survive not only a tragedy but the future. How do you maintain that level of community?

The one thing I find both good and bad about our society is how BIG and powerful corporations are. The bad things are that they are so BIG that they cant collapse. They cannot be replaced by another and thus there policies, practices, and power live as a seperate entity no matter who is in control.

Funny because this is exactly what drives our government. You cant replace these people, they are brought into the ranks, taught to play the games, and perpetuate the entity.

This is what seperates the late 30's early 40's generation from us. We are inheriting the vision of another generation no matter how distorted that original vision has become.

Without the tornado's to clear out the old and bring in the new (at least for BIG companies) there is a good chance that America's jobs will continue to be lost elsewhere. We dont need more startups, we need more startups that have an eye towards being green, solving problems, and providing good jobs. Maybe there is too much altruism in me, but with a population explosion, a global marketplace, and increasing wealth for the top 5 percent of the world and reduced wealth for the middle 40 percent, our current problems will only get worse.

The downfall of all previous empires has been the inability to stand with each other in times of desperation. WWII era Americans did it. The Romans couldnt handle it, the aztecs couldnt survive. The next few generations will have to deal with global climate change on top of reduced clean water and increasing weather severity (drought and floods; severe weather; hurricanes). I have even started on terrorism but that just takes advantage of the despair and will only add to the stress.

I am biased but SCI & TECH may be the only way to intelligently utilize our power for good job generation, problem solving, and being much more green. We can all start by removing our dependence on OIL. I dont care where it comes from. It will run out. Why are we so slow in moving away. 1979. 30 years. we should be driving electric cars en masse. we should be selling them to other countries. The state of Michigan might be better off if that were the case. The car companies need more rapid vision. Where is the next Tucker?

June 16

Classic Day 2 outlook for June 2. Not this year. This year the upper low over the midwest set up shop in late June with a block forecast for the next 184 hours. This should put a hold on severe weather somewhere south of IA, though you can never be too certain of that (the dryline, weak disturbances, diurnal destabilization, etc).

In fact some May25-June15 daily composite geopotential height maps (2006, 2003, 2002, 2001) all indicate a ridge at 500 hPa over the Plains and these were slow years for severe storms in the Plains. The other years were biased toward SW flow with a trough hanging off the S Pac coast (2008) or a more zonal pattern across the Plains (back to 1998). We already know there are favorable patterns for convective storms but there are a lot factors that contribute to the favorable synoptic setup. One thing is certain: this year was favorable for severe storms including the "floods of 08".

I created a figure using the oceanographers temperature salinity diagram [I used the log of the counts rather than the counts to highlight the lower numbers]. The figure shows day of the year along the X axis, and number of tornadoes in the Y axis. Its a 2d histogram basically (using a 7 day bin and a 4 tornado count) for 1979-2007 over the CONUS. Anyway, it shows the double frequency maximum of outbreaks centered near day 130 and day 300. It also shows (via the yellow frequency band) when tornadoes are typically observed (from day 100 to 230 or April to late July). Why show this figure? To highlight the rarity of the number of days where tornado occurrence exceeds around 20. So what happened in 2008?

2008 tornado days in May above 20[4]; 30 [1]; 40[1]; 50+[5].
June 17th [3] [1] [0] [3]

These numbers will come down, but the number of days is impressive. 33 percent of the months May and June had what can be considered outbreak type days. That is obscene. No doubt the tornado counts only spell part of the story. The predominant convective mode was supercellular and thus along with tornados came heavy rain. Seems pretty obvious, but this is one year where a regional climate model should be compared to observations (not for the flood) but for detection of the cape-shear environment.

Break out the ARK

Looks like my former residence is going to be flooding again.

The ingredients for this years severe weather season have all come together perfectly. Moisture, dynamics, timing, and plenty of initiating mechanisms. Something is truly remarkable about this year compared to not only the last 3 years of ho hum seasons, but in general.

Things to look for are the areal average surface moisture bias and cape, the storm track and thus shear, and also the moisture depth. i am becoming increasingly convinced that moisture depth is just as important as variables such as cape. Doubt me? Look at the DVN sounding, which is pretty similar to the ILX sounding at the same time and the DV sounding 6 hours previous.

The bulk of the tornado's occurred downstream from these soundings. But, you say, OAX was also very similar. Well plenty of tor warned storms and plenty of mid level rotation in IA today. But the key: downdraft cape from the freezing level! OAX had a higher DCAPE but its freezing level environment was far dryer. This was an indication that the lid was "stronger" at OAX, or at the very least lower to the ground.

The variable combinations for severe weather are so hard to pick off. But I think "low-level" shear, up to the max moisture depth is important. CAPE in the lower levels is important but indicative of the lower level moisture content. The DCAPE figures in as we include the effects of the lid and any downdraft generation. The downdraft and resulting outflow must be important to the gust front dynamics of these storms since the density gradient helps determine the speed of these features. if the supercell motion and the gust front motion match (a sort of critical level) tornados form (in some circumstances). I have yet to see a full paper dedicated to the structural characteristics of the tornado environment prior to and during tornadogenesis. The focus is always on the tornado and parent mesocyclone.

Someday I hope to work these concepts out. maybe the vortex guys will beat me to it. But they seam bent on understanding the tornado and not necessarily the whole storm in context. The DRC's helped expand the view a little. So did the owl horn signature.

Maybe the Sticknet program will break out some interesting results. RFD's are important. But how and where do they form, and are they common?