Two 500-year floods in 15 years

By: Dr. Jeff Masters , 2:48 PM GMT on June 19, 2008

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The U.S. Geological Survey has preliminary data showing that this month's floods on four of Iowa's rivers--the Cedar, Iowa, Shell Rock, and Wapsipinicon--were 500-year floods. Back in 1993, many rivers in the Midwest also experienced 500-year floods, so the region has endured two 500-year floods in the past 15 years. How can this be? First of all a definition--a 500-year flood is an event that has only a 0.2% chance of occurring in a given year, based on available river flow data. Of course, reliable data only goes back a century at most, so designation of a 500-year flood event is somewhat subjective. Still, it seems rather improbable that two such huge floods should occur within such a short time span, raising the question of whether the floods were, in part, human-caused.

In a provocative story in the Washington Post today, it was pointed out that part of the flooding is due to the draining of wetlands for farming purposes. As nature's natural buffers against flooding are drained and filled to provide room for more farmland, run-off and flooding are bound to increase. Furthermore, as more levees are built to protect more valuable farmland and new developments, flood waters are pushed out of the former areas they were allowed to spread out in and forced into river channels behind the new levees. Even higher levees must then be constructed to hold back the increased volume of water they are asked to contain.

Climate change contributing to flooding?
The heaviest types of rains--those likely to cause flooding--have increased in recent years (see my February blog, "The future of flooding", for more detail). According to the United Nations' Intergovernmental Panel on Climate Change (IPCC) 2007 report, "The frequency of heavy precipitation events has increased over most land areas". Indeed, global warming theory has long predicted an increase in heavy precipitation events. As the climate warms, evaporation of moisture from the oceans increases, resulting in more water vapor in the air. According to the 2007 IPCC report, water vapor in the global atmosphere has increased by about 5% over the 20th century, and 4% since 1970.

Over the U.S., where we have very good precipitation records, annual average precipitation has increased 7% over the past century (Groisman et al., 2004). The same study also found a 14% increase in heavy (top 5%) and 20% increase in very heavy (top 1%) precipitation events over the U.S. in the past century. Kunkel et al. (2003) also found an increase in heavy precipitation events over the U.S. in recent decades, but noted that heavy precipitation events were nearly as frequent at the end of the 19th century and beginning of the 20th century, though the data is not as reliable back then. Thus, climate change is likely partly to blame for increased flooding in the U.S., although we cannot rule out long-term natural variations in precipitation.


Figure 1. Forecast change in precipitation and runoff for the period 2080 to 2099 compared to 1980 to 1999. The forecasts come from the A1B scenario from multiple climate models used for the Intergovernmental Panel on Climate Change (IPCC) 2007 report.

The forecast
According to a multi-model consensus of the climate models run for the Intergovernmental Panel on Climate Change (IPCC) 2007 report, precipitation and river runoff for the Mississippi River drainage basin are expected to increase only slightly by the end of this century (Figure 1). However, more of this rain is expected to fall in heavy precipitation events, the ones most likely to cause flooding. As a result, the U.S. needs to prepare for an increase in the number and severity of 100-year and 500-year flooding events in the coming century.

References
Kunkel, K. E., D. R. Easterling, K. Redmond, and K. Hubbard, 2003, "Temporal variations of extreme precipitation events in the United States: 1895.2000", Geophys. Res. Lett., 30(17), 1900, doi:10.1029/2003GL018052.

Groisman, P.Y., R.W. Knight, T.R. Karl, D.R. Easterling, B. Sun, and J.H. Lawrimore, 2004, "Contemporary Changes of the Hydrological Cycle over the Contiguous United States: Trends Derived from In Situ Observations," J. Hydrometeor., 5, 64.85.

Tropics
It's quiet in the tropics. There are no threat areas to discuss, and none of the models are forecasting tropical storm formation in the next seven days.

Jeff Masters

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904. surfmom
12:04 PM GMT on June 21, 2008
Good morning Storm! Always have properly sized crates & enough food & water, as well as appropriate ID & vaccine information. When you set up your hurricane food stash remember to do so for your pets. ID does help pets get back to their owners IF separated.

If you are an owner of horses,cattle,goats, Llamas etc. Prior to the event of a 'cane have your plans ready. STay or Go - and the where you are going. If you stay be sure your animals are properly ID. A duck tape info tag braided into a horses tail and mane, and the cattle crayon - write the contact phone number on both sides of the animal (in cause it's laying down on one side)Have your large animal medical supplies already on hand - you will not be able to count on the vets in the initial stages.
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903. IKE
7:11 AM CDT on June 21, 2008
Satellite Services Division...or SSD, sure has had a lot of issues lately with their satellite loops....almost daily...glad it's a quiet period in the Atlantic.
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901. cajunkid
11:45 AM GMT on June 21, 2008
Pets in evacuations are a tricky situation. You don't want everyone's pets at a shelter, but you can't leave them behind.

My wife and I are greatful for someone's spoiled poodle we adopted after Katrina. I wish they knew she has a good home.
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900. all4hurricanes
11:53 AM GMT on June 21, 2008
This was an odd Typhoon it followed the basic intensity forecast but went off from the placement forecast usually it's opposite
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899. nrtiwlnvragn
7:54 AM EDT on June 21, 2008
invest_ep932008.invest

EP 93 2008062018 BEST 0 127N 1132W 25 1009 DB
EP 93 2008062100 BEST 0 128N 1142W 25 1010 DB
EP 93 2008062106 BEST 0 129N 1152W 25 1010 DB
EP 93 2008062112 BEST 0 131N 1162W 25 1009 DB
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898. hurricanehanna
11:22 AM GMT on June 21, 2008
Anyone up who can tell me about Fengshen? My hubby is in Manila and I'm having trouble reaching him. I thought it would turn east but looks like it has decided to cut across the island. THanks!
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895. Chicklit
5:20 AM EST on June 21, 2008
Spay and Neuter:
You are to be commended! You wouldn't leave a member of your family behind when you evacuate so why would you leave your pets?!
Our pets, who depend upon us to care for them, are worse equipped to survive natural disasters than humans.
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894. SpaceThrilla1207
9:42 AM GMT on June 21, 2008
anyway, how is your GOM blob doing? What's this of a LLC?
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893. SpaceThrilla1207
9:31 AM GMT on June 21, 2008
7544, there will always be nice-looking waves rolling off the African coast in the diurnal maximus from now until mid-late October...this the prelude to a potentially very active Cape Verde season, as long as the dust out there isn't as bad as it was in 2005 when it was at its worst.
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892. HadesGodWyvern (Mod)
7:57 AM GMT on June 21, 2008
At 6:00 AM UTC Typhoon Fengshen T0806 (950 hPa) located near 12.2N 122.3E has 10 minutes sustained winds of 85 knots with gusts up to 120 knots. The typhoon was reported moving west-northwest slowly

Storm-Force Winds
===============
60 NM from the center

Gale-Force Winds
================
160 NM west from the center
140 NM east from the center

Forecast Position and Intensity
=============================
24 HRS: 14.9N 120.0E - 75 knots (CAT 3)
48 HRS: 17.9N 118.6E - 80 knots (CAT 3)
72 HRS: 21.3N 117.3E - 80 knots (CAT 3)

----
Slight weakening of the system. Romblon and Oriental Mindoro landfall looks likely. Manila might be affected as well.
Member Since: May 24, 2006 Posts: 51 Comments: 45638
891. 7544
7:57 AM GMT on June 21, 2008
its 5 am you gotta see what is just about to come off africa the best one we had so far out there . check it out

Link
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890. IPlayTS3
3:17 PM CST on June 21, 2008
The satellite loop here shows that Fengshen is now moving north. JTWC is so funny. First, Fengshen was forecasted to traverse the Philippine Sea but it kept going west. Next day it was forecasted to move north the Philippines but it kept going west. Now, it is forecasted to move west but it now goes north.

Link
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889. spayandneuter
1:09 AM EDT on June 21, 2008
I am a Animal Disaster Field Responder and I have just returned from working the flood in Cedar Rapids, IA. What a terrible thing they have gone through. We were rescuing the animals that people left behind and even after what we learned in Hurricane Katrina there were still hundreds of animals left behind when people evacuated. We literally rescued over 300 animals from the flood zone.

People, PLEASE LISTEN and spread the word. Take your pets with you when you evacuate! They are not safe in any type of disaster. Have a plan for them, have an evacuation kit for them and for your family.

Here is a good link for information on how to plan for your animals

http://www.hsus.org/hsus_field/hsus_disaster_center/resources/

They may be all you have left when it's over. Please, please please, take them with you when you leave!


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888. Stormchaser2007
4:54 AM GMT on June 21, 2008
CI# /Pressure/ Vmax
5.9 / 933.5mb/112.4kt
Member Since: June 9, 2007 Posts: 4 Comments: 15921
887. Stormchaser2007
4:53 AM GMT on June 21, 2008
Wow


CI# /Pressure/ Vmax
5.9 / 933.5mb/112.4kt
Member Since: June 9, 2007 Posts: 4 Comments: 15921
886. atmoaggie
4:39 AM GMT on June 21, 2008
The 65 knot coverage looks like about a 60 mile diameter.

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885. Levi32
8:33 PM AKDT on June 20, 2008
Lol I've been laughing and laughing these last 3 days. The JTWC had Fengshen going way the heck east of Japan........I pulled up the WV loop 3 days ago and said nah......no way....the models gotta be wrong. Now....12 hours ago the track was east of the Phillipines......now look what it is now....and Fengshen just keeps going west lol. I'm sorry I just can't help laughing it's so funny.



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884. moonlightcowboy
11:29 PM CDT on June 20, 2008
bloghole - deep and wide!
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883. Levi32
8:19 PM AKDT on June 20, 2008
Lol I've been laughing and laughing these last 3 days. The JTWC had Fengshen going way the heck east of Japan........I pulled up the WV loop 3 days ago and said nah......no way....the models gotta be wrong. Now....12 hours ago the track was east of the Phillipines......now look what it is now....and Fengshen just keeps going west lol. I'm sorry I just can't help laughing it's so funny.



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882. TampaSpin
12:15 AM EDT on June 21, 2008
Gang we most diffently have a LLC developing in the BOC.
Member Since: September 2, 2007 Posts: 178 Comments: 20443
881. IPlayTS3
12:14 PM CST on June 21, 2008
Comment 867

Philippines
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880. Tazmanian
9:10 PM PDT on June 20, 2008
look at this go and go this went from 77kt up to 109.8kt and fast

Link
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879. StormJunkie
4:07 AM GMT on June 21, 2008
Evening mlc, good to see ya

100m depth loop
show the current real well. Interesting current just off the E coast as well.
Member Since: August 17, 2005 Posts: 26 Comments: 16874
878. pottery
12:04 AM AST on June 21, 2008
yeah, I understand, Txalways.
I feel the same way about the storms. Like to watch them from afar.
So far, so good, too.
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877. TampaSpin
12:03 AM EDT on June 21, 2008
871. txalwaysprepared 11:45 PM EDT on June 20, 2008

Txalway........your Avator is frightening to me...lol.....what the hell is that.....lol
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876. txalwaysprepared
4:05 AM GMT on June 21, 2008
where can I find the projected path for "Frank"?
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875. StormJunkie
4:03 AM GMT on June 21, 2008
Evening mlc, good to see ya

100m depth loop
show the current real well. Interesting current just off the E coast as well.
Member Since: August 17, 2005 Posts: 26 Comments: 16874
874. Tazmanian
9:02 PM PDT on June 20, 2008
thanks moon
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873. moonlightcowboy
3:58 AM GMT on June 21, 2008
Taz, that's too broad of a statement, really. It depends on several factors that are involved in the cyclogenesis process. Notice in the GOM that there are a few eddys that have spun off the loop already. One is just coming off and there are three larger ones out there. And, there are four or five smaller ones. These will all have warmer water, but not as warm as the loop itself. But, to answer your question best - a storm should intensify over those warmer deeper waters. Factors like the size of the storm, its height, speed, outflow, etc...lots of things. Doesn't necessarily mean if blooms into a major, but yes, it would strengthen.

ALSO, notice the deeper, blue-looking circles: these are "anti-cyclonic" eddys - they spin the other way, and they spin off the warm cyclonic eddys. Cyclonic eddys bring warm water up. Anti-cyclonic one take warm water down. Where the anti-cyclonic ones are located, aquatic life is usually abundant. Fishing is usually good.


Hope that helps (and hope I didn't get it backwards)! lol
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872. jabjb2
3:53 AM GMT on June 21, 2008
if you turn off the first 8 frames and rock it you can see the spin really good http://www.ssd.noaa.gov/goes/east/gmex/loop-vis.html
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871. txalwaysprepared
3:41 AM GMT on June 21, 2008
pottery - thanks. I know it's unlikely we will have to do it again anytime soon. And thankfully too, because my husband is not going to be easily convinced to leave again. This time it would be an evac with a 4 1/2, 2 1/2 and 8 month old LOL. Can you imagine? I don't even want to think about it ;)

I love storms, I really do. It's funny to be so fascinated by something that is so deadly and destructive. It would be nice to watch them develop, get a good couple days out of them and then watch them poof into thin air before hitting land :)
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870. Tazmanian
8:42 PM PDT on June 20, 2008
thanks moon so if any where to run overe that and with light wind shear it could go from a TS up to a cat 4 or 5 hurricane in no time right ???????
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869. HadesGodWyvern (Mod)
3:42 AM GMT on June 21, 2008
Philippines Atmospheric Geophysical Astronomical Services Administration

Typhoon "FRANK" has maintained its strength as it moves towards Mindoro area.

SPECIAL NOTE: expected to cross Mindoro

Tropical Cyclone Bulletin #11
============================
At 11:00 A.M. PST, Typhoon Frank (FENGSHEN) located near 11.9ºN, 122.4ºE or off the coast of Kalibo, Aklan or at 90 kms South of Romblon has sustained winds of 75 knots with gusts up to 90 knots.

Storm Signals Raised
====================

Warning Signal #3 (100-185 km/h)

Luzon Region
1.Romblon
2.Marinduque
3.Oriental Mindoro
4.Occidental Mindoro
5.Lubang Island
6.Calamian Group of Islands

Visayas Region
1.Northern Antique
2.Aklan
3.Capiz

Mindanao Region
1.No Signal Raised

Warning Signal #2 (60-100 km/h)

Luzon Region
1.Masbate
2.Ticao Island
3.Burias Island
4.Sorsogn
5.Albay
6.Camarines Sur
7.Southern Quezon
8.Batangas
9.Laguna
10.Cavite
11.Rest of Northern Palawan

Visayas Region
1.Rest of Antique
2.Iloilo
3.Guimaras
4.Negros Occidental
5.Biliran Island

Mindanao Region
1. No Signals Raised

Warning Signal #1 (30-50 km/h)

Luzon Region
1.Catanduanes
2.Camarines Norte
3.Northern Quezon
4.Polillo Island
5.Rizal
6.Bulacan
7.Pampanga
8.Zambales
9.Bataan
10.Rest of Palawan
11.Metro Manila

Visayas Region
1.Negros Oriental
2.Cebu
3.Leyte
4.Eastern Samar
5.Western Samar
6.Bohol
7.Northern Samar

Mindanao Region
1.No Singal Raised

Public Storm Warning Signal # 1 elsewhere is now lowered.
Residents in low lying areas and near mountain slopes under storm signals are advised to take all the necessary precautions against possible flashfloods and landslides. Likewise, those living in coastal areas under signals 2 and 3 are alerted against big waves or storm surges generated by this typhoon.

Typhoon "Frank" will continue to enhance the Southwest Monsoon and bring rains over the Western section of Mindanao which may trigger flashfloods and landslides.

The public and the disaster coordinating councils concerned are advised to take appropriate actions and watch for the next bulletin to be issued at 5:00 PM today.
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868. moonlightcowboy
10:35 PM CDT on June 20, 2008
TAZ, the loop is running a couple of feet or so higher than the rest of the GOM, and it's plenty warm enough.

Photobucket
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867. pottery
11:39 PM AST on June 20, 2008
Where are you, I Play ?
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866. txalwaysprepared
3:37 AM GMT on June 21, 2008
TS awww but I like listening to you guys better ;) Besides, I used to work with our local mets. Sadly, I don't have a ton of confidence in them.
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865. pottery
11:28 PM AST on June 20, 2008
You have every right to feel freaked, Txalways.
Evacuation with a 2 yr old, and 8 months pregnant? Lady, that would floor me for years.
Check Patrap's blogs, for good advice on preparedness, and stay tuned in all the time. You have one major advantage, in that you have done it all before, and if you have to do it all again, help someone who is in the position you were in then.
In reality, the chances of you having to go through that again are pretty remote, in spite of what me and Taz and MLC are saying.
So dont fret. Its cool.
Member Since: October 24, 2005 Posts: 0 Comments: 24398
864. TampaSpin
11:38 PM EDT on June 20, 2008
859. jabjb2 11:32 PM EDT on June 20, 2008
looks like a spin along 20/93 Link


It sure appears to me also........visible would be nice.
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863. Patrap
10:33 PM CDT on June 20, 2008
GOM 120 Hour Water Surface Temperature Forecast Model (using HYCOM)Link
Member Since: July 3, 2005 Posts: 426 Comments: 128694
862. TampaSpin
11:31 PM EDT on June 20, 2008
857. txalwaysprepared 11:28 PM EDT on June 20, 2008

Your welcome....thats what this blog is for. There is alot of very knowledgeable bloggers that give very good advice and information....but, always listen to your local mets also.
Member Since: September 2, 2007 Posts: 178 Comments: 20443
861. Tazmanian
8:33 PM PDT on June 20, 2008
what would this blog be like if Fengshen was a cat 5 in the gulf of MX right now
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860. IPlayTS3
11:33 AM CST on June 21, 2008


Fengshen is on its way on our place. :-O
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859. jabjb2
3:32 AM GMT on June 21, 2008
looks like a spin along 20/93 Link
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858. Tazmanian
8:28 PM PDT on June 20, 2008
how hot and how deep is the loop eddy in the gulf of MX???
Member Since: May 21, 2006 Posts: 5091 Comments: 115244
857. txalwaysprepared
3:24 AM GMT on June 21, 2008
I just want to say thank you to all the resident "experts" on here who put up with my silly little questions and worries. You are all great ... really!!

Worrying and evacuating from Rita (with a 2 yr old and 8 months preggo) has made me a complete nutso. I tend to freak out a little too easily.

So thank you! You are all wonderful for putting up with me!
Member Since: August 18, 2007 Posts: 0 Comments: 1642
856. moonlightcowboy
10:27 PM CDT on June 20, 2008
TS, I've been on the road a couple of days, and haven't really looked at much yet. Just getting in this evening. But, if shear is weak and there's lower pressure around, things can generate. Checked pressures?
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855. Tazmanian
8:27 PM PDT on June 20, 2008
lol
Member Since: May 21, 2006 Posts: 5091 Comments: 115244
854. Tazmanian
8:27 PM PDT on June 20, 2008
i think we could see 2 to 4 name storms in july
Member Since: May 21, 2006 Posts: 5091 Comments: 115244

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.