Is the U.S. climate getting more extreme?
Is the world's climate getting more extreme, with hotter heat waves, colder cold events, heavier rains, and more extreme droughts? After seeing the unprecedented weather events of 2010 and the equally impressive floods of 2011, it's an important question to be asking. Unfortunately, it's an almost impossible question to answer objectively, because we simply don't have good enough long-term global weather records to do so. However, in the U.S., we do have good enough records to attempt this, and the NOAA National Climatic Data Center (NCDC) has developed a Climate Extremes Index to do so. For 2010, the Climate Extremes Index (CEI) showed that the U.S. had a near-average area experiencing extreme weather conditions. Averaged over decades-long time scales, the U.S. climate has been getting more extreme since 1970, but has not changed significantly over a century-long time scale. The Climate Extremes Index (CEI) is based upon three parameters:
1) Monthly maximum and minimum temperature
2) Daily precipitation
3) Monthly Palmer Drought Severity Index (PDSI)
The temperature data is taken from 1100 stations in the U.S. Historical Climatology Network (USHCN), a network of stations that have a long period of record, with little missing data. The temperature data is corrected for the Urban Heat Island effect, as well as for station and instrument changes. The precipitation data is taken from 1300 National Weather Service Cooperative stations. The Climate Extremes Index defines "much above normal" as the highest 10% of data, "much below normal" as the lowest 10%, and is the average of these five quantities:
1) The sum of: (a) the percentage of the United States with monthly maximum temperatures much below normal, and (b), the percentage of the United States with monthly maximum temperatures much above normal.
2) The sum of: (a) the percentage of the United States with monthly minimum temperatures much below normal, and (b), the percentage of the United States with monthly minimum temperatures much above normal.
3) The sum of: (a) the percentage of the United States in severe drought each month (equivalent to the lowest tenth percentile) based on the Palmer Drought Severity Index (PDSI), and (b), the percentage of the United States with severe moisture surplus (equivalent to the highest tenth percentile) based on the PDSI.
4) Twice the value of the percentage of the United States with a much greater than normal proportion of precipitation derived from extreme (equivalent to the highest tenth percentile) 1-day precipitation events.
5) The sum of: (a) percentage of the United States with a much greater than normal number of days with precipitation, and (b), percentage of the United States with a much greater than normal number of days without precipitation.
Figure 1. The Annual Climate Extremes Index (CEI), updated through 2010, shows that U.S. climate has generally been getting more extreme since the early 1970s, but that the 2010 climate was just slightly more extreme than average. On average since 1910, 21% of the U.S. has seen extreme conditions in a given year (thick black line), and in 2010 this number was about 24%. Image credit: National Climatic Data Center.
As summarized by Gleason et al. (2008), the National Climatic Data Center concludes that based on the Climate Extremes Index, the percentage of the U.S. seeing extreme temperatures and precipitation generally increased since the early 1970s. These increases were most pronounced in the summer. No trend in extremes were noted for winter. The annual CEI index plot averaged for all five temperature and precipitation indices (Figure 1) showed that four of the ten most extreme years on record occurred since 1996. However, some very extreme years also occurred in the 1910s through 1950s, in association with widespread extreme drought and above-average temperatures. The most extreme year in U.S. history was 1998, with 1934 a close second. The year 1998 was the hottest year in U.S. history, with a record 78% of the U.S. experiencing minimum temperatures much above normal. That year also had a record 23% of the U.S. with much greater than normal precipitation from extreme 1-day precipitation events. The 1934 extreme in CEI was due in large part because of the most widespread drought of the century--a full 52% of the U.S. was affected by severe or extreme drought conditions. That year also saw a record 64% of the U.S. with much above normal maximum temperatures.
Maximum and minimum temperatures
It is very interesting to look at the five separate indices that go into the Climate Extremes Index. Today I'll look at temperature, and focus on drought and precipitation in my next post. The portion of the U.S. experiencing month-long maximum or minimum temperatures either much above normal or much below normal has been about 10% over the past century (black lines in Figures 2 and 3.) However, over the past decade, about 20% of the U.S. has experienced monthly maximum temperatures much above normal, and less than 5% has experienced maximum temperatures much cooler than normal. Minimum temperatures show a similar behavior, but have increased more than the maximums (Figure 3). Climate models minimum temperatures should be rising faster than maximum temperatures if human-caused emissions of heat-trapping gases are responsible for global warming, which is in line with what we are seeing in the U.S. using the CEI.
While there have been a few years (1921, 1934) when the portion of the U.S. experiencing much above normal maximum temperatures was greater than anything observed in the past decade, the sustained lack of maximum temperatures much below normal over the past decade is unique. The behavior of minimum temperatures over the past decade is clearly unprecedented--both in the lack of minimum temperatures much below normal, and in the abnormal portion of the U.S. with much above normal minimum temperatures. Remember that these data ARE corrected for the Urban Heat Island effect, so we cannot blame increased urbanization for the increase in temperatures.
Figure 2. The Annual Climate Extremes Index (CEI) for maximum temperature, updated through 2010, shows that about 10% of U.S. had maximum temperatures much warmer than average during 2010. This was right near the average from the past 100 years (thick black line.) Image credit: National Climatic Data Center.
Figure 3. The Annual Climate Extremes Index (CEI) for minimum temperature, updated through 2010, shows that about 35% of U.S. had minimum temperatures much warmer than average during 2010. This was the 7th largest such area in the past 100 years. The mean area of the U.S. experiencing minimum temperatures much warmer than average over the past 100 years is about 10% (thick black line.) Image credit: National Climatic Data Center.
I'll have a new post on Tuesday, when I'll talk about how extremes of drought and precipitation have changed in the U.S. (I may talk instead about the developing winter storm for the Appalachians and Northeast coming Wednesday and Thursday this week, though.)
References
Gleason, K.L., J.H. Lawrimore, D.H. Levinson, T.R. Karl, and D.J. Karoly, 2008: "A Revised U.S. Climate Extremes Index", J. Climate, 21, 2124-2137.
The National Climatic Data Center has a more in-depth discussion of the Climate Extremes Index for the U.S. on a regional and seasonal basis during 2010. In some regions, such as the Southeast U.S., 2010 was a remarkably extreme year.
Jeff Masters
Reader Comments
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...The SO2 currently in the atmosphere is masking additional warming we would see otherwise..."
255 Levi32 "The cause you mention of cooling/flattening between 1945 and 1977 has nothing to do with the current flattening trend during the last 10 years."
You haven't been paying attention to news from China and India. Sulfur dioxide emissions peaked circa 1990, then began falling (mostly due to the collapse of the Russian and former SovietBloc economies).
However while those nations' industrial pollution fell, China's (then India's) industrial output began booming. By 2002, total SO2 emissions began climbing again.
China became the largest consumer of fossil fuels, and the greatest emitter of sulfur dioxide. Increasing at an average rate of ~7.3% per year, it has doubled its emissions during the past 9years.
Tropical Cyclone Advisory #15
SEVERE TROPICAL CYCLONE WILMA (06F)
18:00 PM FST January 25 2011
===================================
Warnings for Tonga
======================
A Gale Wind Warning is now in force for Ata
A Strong Wind Warning remains in force for 'Eua, Tongatapu, and Ha'apai group
Tropical Cyclone Warnings for Fiji
====================================
A Gale Warning is in force for Fulaga, Ogea, Vatoa, Ono-I-Lau, and nearby smaller islands.
At 6:00 AM UTC, Severe Tropical Cyclone Wilma, Category Three (965 hPa) located at 21.5S 177.2W has 10 minute winds of 70 knots and is reported as moving southwest at 20 knots. Position FAIR based on multispectral infrared/visible imagery and peripheral surface observations.
Hurricane Force Winds
======================
20 NM from the center
Storm Force Winds
=================
30 NM from the center
Gale Force Winds
================
100 NM from the center in the eastern semicircle and 60 NM from the center elsewhere
Additional Information
=========================
Cyclone has intensified over the last 24 hours. Primary band tightly wrapping around low level circulation center. Outflow good to the north and south but restricted elsewhere. System lies under an upper diffluent region. CIMSS indicates a weak sheared environment along the forecast path. Sea surface temperature is around 28C.
Dvorak analysis based on enhanced infrared radar eye pattern with DG eye LG surrounding yielding DT=5.0, MET=5.0, PT=5.0. Final Dvorak T number based on DT.
Dvorak Intensity: T5.0/5.0/D1.5/24HRS.
Most global models move cyclone WILMA southwest with some intensification.
Forecast and Intensity
============================
12 HRS: 23.0S 179.8E - 65 knots (CAT 3)
24 HRS: 24.1S 177.1E - 65 knots (CAT 3)
48 HRS: 25.8S 173.4E - 75 knots (CAT 3)
The next Tropical Disturbance Advisory from Fiji Meteorological Services will be issued at around 14:30 PM UTC..
Local JAX NWS did not even have an HWO on their forecast page at 10pm last night! I told co-workers, it'd gonna be a stormy day, get ready your weather radios and they are like, but it's just supposta rain.
Oh and NOW- - NOW the local NWS page has severe written everywhere!! Why did they not keep up with Tampa and Melbourne? Tampa and Melbourne had been touching on the severe potential since Sunday.
I think my "local" NWS mets have been outsourced....to like Utah, or the moon, or something.
grrrrrr
http://www.northstudio360.com/portfolio/nimmo-bay-helicopter-adventure-resort-360-video
(staggers away from blog, bounces into wall...)
poor Nea does not realize that he has embedded a running video. He's probably in the shower right now thinking "hmmmm...did I?"
gotta run- 16 hour day today (sigh)
peace ya'll
Ya'll have a good one...
That's really cool Nea.
Rain outside and 49.5.
lol its probably because they were playing it lazy or way too conservative, but you know, when the main prediction office is calling for severe weather, they were kinda forced to now at the last minute :)
honestly though, I've seen these systems pan out many times, more than likely, The I-4 corridor starting with me will get wacked, but Jacksonville will probably miss the strong storms.
That's just something to keep in mind, I'm not actually forecasting that though, lol
I think about a lot of things in the shower...but GW isn't one of them... ;-)
Wait--why would I be thinking about George Washington while I'm in the shower?
Glad to know that:)
Rain is about over, for now, for my area. I had .16 inches of rain. Forecasted to have between 1-2 inches. Looks unlikely.
NATIONAL WEATHER SERVICE MIAMI FL
440 AM EST TUE JAN 25 2011
FLZ063-066>075-168-172>174-260045-
GLADES-HENDRY-INLAND PALM BEACH-METRO PALM BEACH-COASTAL COLLIER-
INLAND COLLIER-INLAND BROWARD-METRO BROWARD-INLAND MIAMI DADE-
METRO MIAMI DADE-MAINLAND MONROE-COASTAL PALM BEACH-
COASTAL BROWARD-COASTAL MIAMI DADE-FAR SOUTH MIAMI DADE-
440 AM EST TUE JAN 25 2011
...SLIGHT RISK OF SEVERE THUNDERSTORMS LATE TODAY THROUGH EARLY WEDNESDAY...
...HIGH RISK OF DANGEROUS RIP CURRENTS ALONG THE ATLANTIC BEACHES TODAY...
...SMALL CRAFT ADVISORY ATLANTIC WATERS AND BISCAYNE BAY THROUGH WEDNESDAY...
THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH FLORIDA.
.DAY ONE...TODAY AND TONIGHT
RIP CURRENTS: STRONG EAST TO SOUTHEAST WINDS AT AROUND 20 MPH WITH HIGHER
GUSTS WILL RESULT IN A HIGH RISK OF DANGEROUS RIP CURRENTS ALONG THE
ATLANTIC BEACHES OF PALM BEACH, BROWARD AND MIAMI-DADE COUNTIES TODAY
AND THIS EVENING.
THUNDERSTORMS: THUNDERSTORMS CHANCES WILL INCREASE SIGNIFICANTLY
FROM THIS AFTERNOON THROUGH WEDNESDAY MORNING AHEAD OF A STRONG
COLD FRONT EXPECTED TO MOVE ACROSS SOUTH FLORIDA WEDNESDAY
AFTERNOON. THERE IS A SLIGHT RISK OF SEVERE WEATHER WITH THESE
STORMS. THE MAIN IMPACT WILL BE STRONG GUSTY WINDS AND VERY HEAVY
RAINFALL.
WATERSPOUTS: WATERSPOUTS WILL BE POSSIBLE TODAY, ESPECIALLY FROM
THIS AFTERNOON AND THROUGH THE EVENING HOURS ACROSS THE GULF OF
MEXICO AND ATLANTIC WATERS AS SHOWERS AND STORMS DEVELOP AHEAD OF
THE APPROACHING FRONT.
WIND: STRONG EAST TO SOUTHEAST WINDS OF 20 TO 25 KNOTS WITH HIGHER
GUSTS WILL AFFECT THE ATLANTIC WATERS AND BISCAYNE BAY TODAY. A
SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THESE WATERS.
WAVES: SEAS UP TO 7 FEET ARE EXPECTED ACROSS PORTIONS OF THE
ATLANTIC WATERS TODAY.
.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY
ANOTHER BOUT OF COOL WEATHER IS EXPECTED BEHIND THE FRONT FOR
LATE IN THE WEEK WITH LOWS AGAIN DROPPING INTO THE 40S ACROSS MUCH
OF THE AREA BY FRIDAY AND INTO THE UPCOMING WEEKEND...WITH EVEN
MID TO UPPER 30 DEGREE READINGS EXPECTED ACROSS THE LAKE
OKEECHOBEE REGION.
.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AS THUNDERSTORMS
DEVELOP AHEAD OF THE APPROACHING FRONT. SPOTTERS ARE ENCOURAGED TO
REPORT HIGH WIND, HAIL AND FLOODING TO THE NATIONAL WEATHER
SERVICE FORECAST OFFICE IN MIAMI.
FOR MORE INFORMATION...VISIT THE NATIONAL WEATHER SERVICE IN
MIAMI WEBSITE AT WWW.WEATHER.GOV/MIAMI.
$$
...THUNDERSTORM IMPACT...
THERE WILL BE A SLIGHT RISK OF SEVERE THUNDERSTORMS LATER TODAY
AND OVERNIGHT AS A LOW PRESSURE CENTER TRACKS ALONG THE GULF COAST
AND THEN ACROSS NORTH FLORIDA TONIGHT...WITH A COLD FRONT SWEEPING
INTO THE EAST GULF AND THEN CROSSING THE STATE. THE PRIMARY
THREATS WILL BE DAMAGING WINDS AND TORNADOES. THE TIME OF GREATEST
THREAT WILL BE LATER THIS AFTERNOON BUT...AS A SQUALL LINE IS
EXPECTED FORM THE IN THE EAST GULF AHEAD OF THE FRONT...WILL
LIKELY CONTINUE INTO THE EVENING HOURS. IN ADDITION THESE STORMS
WILL BE ACCOMPANIED BY WIDESPREAD RAIN RESULTING IN LOCALIZED
FLOODING. STORMS WILL BE ENDING LATE TONIGHT OR EARLY WEDNESDAY
MORNING.
I guess the meteorolgist calling it "Tornado Tuesday" may be wrong for our area.
NATIONAL WEATHER SERVICE MOBILE AL
441 AM CST TUE JAN 25 2011
.SHORT TERM [TODAY AND TONIGHT]...A VERY CHALLENGING FORECAST TODAY
AS REALITY IS DISAGREEING GREATLY WITH THE FORECAST MODELS. WHILE
RAIN HAS DEVELOPED ACROSS THE CWA OVERNIGHT IN RESPONSE TO
STRENGTHENING ISENTROPIC LIFT AS LOW PRESSURE ORGANIZES OFF THE LA
COAST...IT HAS NOT BEEN NEAR HAS HEAVY AS PREVIOUSLY ADVERTISED AND
THE HEAVY RAIN THREAT IS DECREASING. THE MAIN CULPRIT FOR THIS IS
THE MID LEVEL DRY SLOT WHICH HAS BEEN MORE RAPID IN ITS EASTERLY
MOVEMENT THAN ANY GUIDANCE HAS SUGGESTED. IN ADDITION...DEEP
CONVECTION HAS DEVELOPED TO THE SOUTH OF SOUTHEAST LOUISIANA AND
THE SUBSIDENCE ON ITS PERIPHERY MAY BE CONTRIBUTING TO THE DECREASE
IN RAINFALL ACROSS OUR AREA. ANOTHER NOTE IS THAT THE PRIMARY LIFT
HAS BEEN IN THE FORM OF ISENTROPIC LIFT...WHILE FRONTOGENESIS HAS
NOT BE PARTICULARLY STRONG AS THE BAROCLINIC ZONE OVER THE NORTHERN
GULF IS NOT AS TIGHT...WHICH CAN BE SEEN BY LACKLUSTER WINDS
OFFSHORE COMPARED TO MODEL FORECASTS.
RADAR TRENDS CONTINUE TO SHOW A DECREASE IN PRECIP COVERAGE TO THE
SOUTHWEST OF THE CWA...AND IT WAS HARD TO JUSTIFY MAINTAINING
CATEGORICAL POPS AS GUIDANCE SUGGESTS. HOWEVER...WILL ERR ON THE
SIDE OF CAUTION FOR NOW AND KEEP HIGH POPS FOR THE FIRST PART OF THE
MORNING (THROUGH 15Z). THE SURFACE LOW WILL CONTINUE TO SKIRT THE
LA COAST THIS MORNING AND WE SHOULD SEE THE WARM FRONT OVER THE
NORTHERN GULF BECOME BETTER DEFINED. THIS INCREASE IN FRONTOGENIC
FORCING MAY BE ENOUGH TO RESULT IN SOME REDEVELOPMENT OF PRECIP
THROUGH MID MORNING. HOWEVER...CROSS SECTIONS REVEAL THAT MOISTURE
ABOVE 850 MB RAPIDLY DRIES OUT BETWEEN 15Z-18Z...AND ALL SIGNIFICANT
PRECIP IS LIKELY TO BE OVER WITH BY NOON AND EVEN SOONER OVER THE FAR
WESTERN ZONES. MEANWHILE...THE SFC LOW WILL TRAVEL VERY CLOSE TO THE
COAST AND DEPENDING ON WHICH MODEL YOU LOOK OUT COULD BE JUST INLAND
OR JUST OFFSHORE. GIVEN THE RAPID CLEARING OF PRECIP EXPECTED BY
MIDDAY...WOULD NOT BE SURPRISED TO SEE SOME BREAKS IN CLOUD
COVER...WHICH MAY HELP THE WARM SECTOR TO MOVE NORTH CLOSER TO THE
COAST. LEANED TOWARD THE WARMER SIDE OF GUIDANCE FOR MUCH OF THE AREA
FOR HIGHS...EXCEPT THE FAR NW CWA. LIKELY TO SEE A LARGE SPREAD IN
HIGHS...RANGING FROM NEAR 50 FAR NORTH TO LOW-MID 60S ACROSS THE
COAST.
Patrap, what is that single point in the gulf that seems to be putting up a HUGE moisture plume. Is someone seeding the clouds from a boat? The narrow stream of clouds looks so odd.
The clouds come down to a fine, low level, point.
Is it just a sharp frontal boundary?
NATIONAL WEATHER SERVICE JACKSONVILLE FL
515 AM EST TUE JAN 25 2011
FLZ020>025-030>033-035>038-040-GAZ132>136-149>154-162>166-261100-
HAMILTON-SUWANNEE-COLUMBIA-BAKER-NASSAU-DUVAL-UNION-BRADFORD-CLAY-
ST JOHNS-GILCHRIST-ALACHUA-PUTNAM-FLAGLER-MARION-COFFEE-
JEFF DAVIS-BACON-APPLING-WAYNE-ATKINSON-WARE-PIERCE-BRANTLEY-
INLAND GLYNN-COASTAL GLYNN-ECHOLS-CLINCH-CHARLTON-INLAND CAMDEN-
COASTAL CAMDEN-
515 AM EST TUE JAN 25 2011
THIS OUTLOOK IS FOR NORTHEAST FLORIDA AND SOUTHEAST GEORGIA.
.DAY ONE...TODAY AND TONIGHT...
...SLIGHT CHANCE OF STRONG TO SEVERE THUNDERSTORMS LATE THIS
AFTERNOON THROUGH TONIGHT FOR NORTHEAST FLORIDA AND EXTREME
SOUTHEAST GEORGIA...
...DAMAGING WINDS AND ISOLATED TORNADOES POSSIBLE...
LOW PRESSURE OVER THE CENTRAL GULF COAST WILL MOVE EAST TODAY. AHEAD
OF THE LOW AND THE ASSOCIATED SHARP MID AND UPPER LEVEL TROUGH...
WIDESPREAD RAINS WILL DEVELOP AND SPREAD ACROSS THE AREA. SOME OF
THIS RAINFALL MAY BECOME LOCALLY HEAVY DURING THE AFTERNOON AND
EVENING HOURS WITH 1 TO 2 INCH RAIN AMOUNTS POSSIBLE.
INCREASING INSTABILITY WILL LEAD TO THUNDERSTORM DEVELOPMENT ACROSS
PORTIONS OF NORTHEAST FLORIDA AND EVENTUALLY EXTREME SOUTHEAST
GEORGIA. ISOLATED STRONG TO SEVERE STORMS MAY BEGIN TO DEVELOP OVER
NORTH CENTRAL FLORIDA DURING THE AFTERNOON HOURS. THESE STORMS WILL
MOVE RAPIDLY NORTHEAST. A MORE ORGANIZED SQUALL LINE IS EXPECTED TO
MOVE INTO THE AREA LATE IN THE AFTERNOON AND DURING THE EVENING
HOURS. THUNDERSTORMS WILL BE CAPABLE OF PRODUCING DAMAGING WIND
GUSTS AND POSSIBLY ISOLATED TORNADOES ALONG WITH DEADLY
CLOUD-TO-GROUND LIGHTNING. THE GREATEST THREAT OF SEVERE STORMS WILL
BE ALONG AND SOUTH OF A SAINT AUGUSTINE TO GAINESVILLE LINE.
THERE WILL BE A MODERATE RISK OF RIP CURRENTS AT AREA BEACHES TODAY.
No Boat involved.
Unless itsa very BIG Boat.
Takes a while for the planet to cool off after a very strong El Nino and record temperatures. Expect a continued decline for the rest of the year.
With the cold anomalies in the Pacific, the earth will cool down some more this year. Just takes some time.
Tallahassee, Base Reflectivity 0.50 Degree Elevation Range 248 NMI
Mixed layer CAPE (MLCAPE)is probably a better parameter to look at. Mix up the lowest 100mb of atmosphere and you get a better sense of the instability that is actually available to the updraft. Kinda takes into account any cooler more stable air at the surface.
"Here I come, I come, I come, I come....."
(Peak of just under 1000 on the peninsula)
Hey, I hear you. I'd love to see the government start some of volunteer/only way to maintain long term unemployment payments /etc scheme to re-plant and just clean up the US - from inner cities to outer farms.
NATIONAL WEATHER SERVICE MOBILE AL
735 AM CST TUE JAN 25 2011
.UPDATE...A DECREASE IN PRECIP COVERAGE ON RADAR CONTINUES TO BE
NOTED. DUE TO THIS...HAVE LOWERED POPS TO THE CHANCE RANGE THIS
MORNING. THE SURFACE LOW IS CENTERED JUST WEST OF HOUMA LOUISIANA.
AS IT TRACKS FURTHER EAST CLOSE TO OUR COASTLINE...WILL SEE SOME
PASSING SHOWERS...PRIMARILY THIS MORNING. LOOKS LIKE THE BEST CHANCE
FOR PRECIP WILL BE IN THE NW ZONES AS RADAR SHOWS A NARROW BAND OF
RAIN MOVING EAST OUT OF SW MS. THE MID LEVELS DRY OUT FURTHER AS THE
DAY PROGRESSES AND THE CHANCES FOR ANY MEASURABLE PRECIP DECREASES
EVEN MORE THIS AFTERNOON. UPDATE ALREADY SENT. TAKING A LOOK AT THE
SCOREBOARD...MOTHER NATURE 1...MODEL GUIDANCE 0. 34/JFB
Yeah, there are people doing good work out there, but not nearly as much as needs to be done. We just have to do it wisely, because a poorly-thought out project can be even worse than nothing. We are still dealing with many of these: invasive species introduced for erosion control that actually increase erosion; channelized rivers that don't reduce flooding; drained wetlands; inappropriately placed/built dams, etc etc etc
Dams causing sediment deposition upstream of where it should, depleting sediment downstream. Us cementing the walls of tributaries. Us building structures to prevent flooding in floodplains only means that flooding will occur somewhere that it shouldn't.
We cause most of the flooding and the wetland erosion (in active delta areas)...
All the while, someone will say that water levels are at record highs, or flooding exceeded highest levels ever, or, such and such a place has never flooded before, etc. The cause? AGW over the last 100 years, of course. (Anthropogenic Gradual change of the Watersheds)
Add to that the massive increase of population next to the water, and those floods are becoming more destructive.
More people, more homes, more crops close by - all wiped out by those natural floods.
Some of the rivers in Asia have flooded thousands of times over the past 1000 years.
Oh thank the Lord!
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