Hawaiians 'won't know what rainfall is'

Apologies in advance for the Vinerism.

From the University of Hawaii ‑ SOEST, something that doesn’t seem to be a problem based on the past data I’ve found:

whaw_rainfall[1]

Source: USGS

It seems clear when you look at the peaks of 1997/1998 and 2004/2005 (both big El Niño years) that Hawaii is a slave to ENSO more than anything else. Even in the press release they admit their best models can’t predict future rainfall reliably, and even though new approach (which is the focus of the new paper) falls short. So, given their blunt admissions of uncertainty, I don’t even know why this press release exists – Anthony

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Less rainfall expected for the Hawaiian Islands

Almost imperceptibly, rainfall over the Hawaiian Islands has been declining since 1978, and this trend is likely to continue with global warming through the end of this century, according to a team of scientists at the University of Hawaii at Manoa (UHM) and the University of Colorado at Boulder. This latest Hawaii rainfall study, published in the March 13, 2013, early online issue of the Journal of Geophysical Research, supports previous work conducted at the University of Hawaii. What has been unclear, however, is whether this drying trend will continue.

“For water resource and ecosystem management, and for other societal needs, we need to know whether this drying trend will continue this century,” says lead investigator Oliver Elison Timm at the International Pacific Research Center, UHM.

As of now, not even cutting edge climate models have enough resolution to capture the diverse rainfall pattern over Hawaii, where dry and wet areas often lie only a mile or even less apart.

To work around this problem, the team devised a method called ‘statistical downscaling.’ They first got a take on the effects of the general drying trend on local heavy-rain days by reanalyzing observations from 1978 to 2010 at 12 rain-gauge stations spread throughout the islands. Studying hundreds of weather patterns during such days, they identified the typical atmospheric circulation patterns in the North Pacific that favor heavy rains over Hawaii.

“The patterns we saw did not surprise us,” recalls Elison Timm. “For example, we found that the typical winter Kona storms with moist air-flow from the South often produce torrential rains in the islands.”

Using those weather patterns linked to heavy rains, the team developed a statistical model that estimates the number of heavy rain events during a year. They found that the large circulation patterns over the mid-latitude and tropical North Pacific have already shifted since 1978 so that fewer weather disturbances reach the Islands during the rainy season from November through April.

“We can’t predict individual rain events with our method,” clarifies Professor Thomas W. Giambelluca, Department of Geography, UHM, “but it gives us a very good estimate of the number of heavy rain events in a given season based on the large-scale atmospheric circulation patterns.”

Combining information from their statistical model and cutting-edge climate models driven with the projected increase in greenhouse gases until the end of this century, the scientists conclude that we can expect the recent trend towards drier winter seasons with fewer heavy-rain days to continue through the end of this century.

“It is extremely difficult to take all the uncertainties into account and our overall result may not apply to all sites in Hawai’i,” cautions Senior Researcher Henry Diaz from the University of Colorado. “We are just beginning to understand the details of how climate change will affect the Hawaiian Islands. We do not know yet how further warming will impact extreme heavy downpours.”

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Citation:

Oliver Elison Timm, Mami Takahashi, Thomas W. Giambelluca, and Henry F. Diaz, 2013: On the Relation between Large-Scale Circulation Pattern and Heavy Rain Events over the Hawaiian Islands: Recent Trends and Future Changes. Journal of Geophysical Research, (early online-release in March 2013, http://onlinelibrary.wiley.com/doi/10.1002/jgrd.50314/abstract )

Funding:

The project was supported by grants from the U.S. Fish and Wildlife Service through the Pacific Island Climate Change Cooperative and the Pacific Islands Climate Science Center. Additional funding was provided jointly by the U.S. Army Corps of Engineers, Honolulu District, and the Commission on Water Resource Management, Hawaii Department of Land and Natural Resources.

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oldseadog

Seems there have been several periods recently when the rainfall was, for 3 or 4 years in a row, quite a bit lower than the average.
What effect did this have on agriculture and on civic water supplies? Was there a problem?

BillyV

Anthony asks: “I don’t even know why this press release exists – Anthony”
Its: “The project was supported by grants from the U.S. Fish and Wildlife Service through the Pacific Island Climate Change Cooperative and the Pacific Islands Climate Science Center.”
Publish or perish. One has to issue a press release after spending considerable money and most will think it is an important study to deflect any criticism the money spent was justified. If you are lucky to have a “grant”, you better post something, and it must be politically correct.

OT: On an earlier thread I posted a note about vulnerability of ‘Rate this’ (thumbs –up –down) facility, and now I am pleased to notice that it’s not there any more (or is it just my pc?).

Auto

““For water resource and ecosystem management, and for other societal needs, we need to know whether this drying trend will continue this century,” says lead investigator Oliver Elison Timm at the International Pacific Research Center, UHM.”
Even in the graph supplied, there is substantial variation – to the eye, never mind the statistician’s fine tooth comb.
I guess Lead Investigator [and High Priest of the Church of the Cagw] Timms,inexplicably, doesn’t care to look more than a generation or so back.
Plainly, in a generation, we cover the whole panoply of events that the Earth’s weather system can possibly contrive/experience/combine to show.
[Moderator, please advise: do I need to include ‘>SARC<'?]
I woder if the High Priest noticed the syclical nature of the figure shown.
Auto

Auto

Better:
I wonder if the High Priest noticed the cyclical nature of the figure shown.
Sorry!

adrian smits

That is kind of weird. Their first statement says rainfall has gone down almost imperceptibly and then they proceed to predict something completely different.WUWT?

From the “been there, done it, got the T Shirt” dept, I ran with a list of 1971 Extreme Weather Events a couple of years ago, as the year 2011 was, well, 40 years afterwards.
And one of the events I found was :-
Hawaii – The drought on Maui was described as the worst in 22 years.
http://www.maui-lahaina-sun.com/strange-maui-drought.html
Seems like there is nothing new!

Gary Pearse

“Studying hundreds of weather patterns during such days, they identified the typical atmospheric circulation patterns in the North Pacific that favor heavy rains over Hawaii.”
You mean the NWS never did this before? Pretty laid back for such an organization.

Doug UK

Well based upon Viners assertion in March 2000 that we in the UK will not see snow again”-
“According to Dr David Viner, a senior research scientist at the climatic research unit (CRU) of the University of East Anglia,within a few years winter snowfall will become “a very rare and exciting event”.
“Children just aren’t going to know what snow is,” he said.”
Can someone put me in touch with an importer in Hawaii as I have bought a load of Umbrellas and the market for them in Hawaii is now assured.

Billy Liar

This really is top of the range climate prediction. They discover that ‘rainfall over the Hawaiian Islands has been declining since 1978‘ and make a prediction that this will continue: ‘we can expect the recent trend towards drier winter seasons with fewer heavy-rain days to continue through the end of this century‘.
This is real value for tax payer dollars. It’s rare to find such talent amongst climatologists.
/sarc

Alan Watt, Climate Denialist Level 7

On the big island of Hawaii alone there are multiple climatic zones ranging from rain forest to almost desert coastal lava fields. Rainfall variations are enormous over distances of 30 miles or less. An “average rainfall” over just that one island is meaningless. See this chart . The lowest average shown on the big island is 10.6 inches (269mm) at Puukohola Heiau up to 126.7 inches (3219mm) at Hilo. These two points are 65 miles apart by road. I don’t see a figure for annual rainfall in Waimea, which is probably only 10 miles from Puukohola, but it’s in a rain forest zone (Kohala Forest) and probably gets as much rain as Hilo. If you include the top of Mauna Kea where the observatories are, annual rainfall is 0.
I would assume people at the University of Hawaii would be aware of this, as they manage the observatories on Mauna Kea and have an observatory office in Waimea.
This is another example that averaging data destroys information.

TomRude

Another fallacy:
“Almost imperceptibly, rainfall over the Hawaiian Islands has been declining since 1978, and this trend is likely to continue with global warming through the end of this century.”
It’s really too bad pressure data show that on the contrary, the meteorological evolution shows an increasing frequency of anticyclones penetrating deeper southward… Surely, higher pressure system are not the result of “global warming” for these modelers? Furthermore, higher pressure systems do explain a dryer Hawaii. Graham and Diaz 2001 found increased cyclonic activity in the Aleoutian low… probably “global warming”… sarc.
Let’s also appreciate that when they ““We are just beginning to understand the details of how climate change will affect the Hawaiian Islands…”, they are talking about the North Pacific which the hawaiian Island represent 0.00034%… that is a zone where MPHs anticyclones can roam virtually free of any continental interference and they just figuring out the details… No what they are just figuring out is how to join the bandwagon, torturing data and publish papers sucked out of their finger.

jc

Anthony, you really don’t know why this Press Release exists? With your experience of “Climate Science”? Perhaps they had to rush it out before it got soggy in a deluge.

clipe

Almost imperceptibly, rainfall over the Hawaiian Islands has been declining since 1978,
Almost “imperceptibly”? Better than “insidious” I suppose.

clipe

correction
“Almost imperceptibly”? Better than “insidiously” I suppose.

Mac the Knife

Combining information from their statistical model and cutting-edge climate models driven with the projected increase in greenhouse gases until the end of this century, the scientists conclude that we can expect the recent trend towards drier winter seasons with fewer heavy-rain days to continue through the end of this century.
Parapharsing:
Yep! That’s the way we modeled and programmed them to behave and they gave us the answer we wanted…. after sufficient torture of the the limited real data, of course. We predict it will continue to get drier until it starts to get wetter again. Until then, it’s worse than we thought and it’s your fault.
MtK
PS: def – Parapharsing: Paraphrasing asinine pseudoscience as farce.

Louis Hooffstetter

“Combining information from their statistical model and cutting-edge climate models….”
“Cutting Edge Climate Model”?
Ha, ha, ha… my new favorite oxymoron.

ANH

‘cutting-edge climate models’
Hahahahahahahahahahaha!!!!!!!!

Janice Moore

Vukcevic — at LAST, I can finally answer a question on this site! The thumbs up/down is gone from my pc, too. Based on a sampling population of 2 and a logical inference, THE THUMBS ARE GONE. #:)

ShrNfr

Anthony, you know quite well why this exists. FUNDING!!!!

Auto

Thumbs are gone here in the UK too. [I did click a couple, so not utterly innocent . . . .]

John from East Lansing

Will Hawaiians still know what snow is? http://www.hawaiiinfoguide.com/hawaii_skiing.htm

zootcadillac

Nobody panic. We’ll just send them some of the snow we are inundated with every winter in the UK. That will cheer them up. Oh wait, perhaps I’m just imagining snow?

Box of Rocks

So how do I get on the gravy train @ CU – Boulder?
You get to do “science” then there is beer and biking…

Horse manure! Hawaii has plenty of rainfall. Every island’s north shore is drenched year round. And hot, dry places like Lahaina and Kihei normally have little rainfall. Water is pumped in from the north shore of Maui, and there is never a shortage.
This is just another cherry-picked example of wild eyed arm-waving over local natural variablity. There is nothing either unusual or unprecedented happening, and Hawaii isn’t going to run out of rainfall. Taxpayers deserve a refund for this wasted grant money.

squid2112

Heh…. pile some more junk science on the fire … what’s another log?

wayne

“So how do I get on the gravy train @ CU – Boulder?”
Sell your soul.

AndyB

There must be a way to avoid this type of conflict of interest in the funding of this type of research. Has it always been this way with government funding for research or is this unique to climate research?

MattN

Wait a minute. I distinctly remember ReallywrongClimate saying specifically that more and more El Ninos were going to occur due to global warming (in fact, the PDO was never ever going to go negative again, according to them). And if Hawaii CLEARLY gets more rain in El Nino years (according to the observed data), then global warming obviously would mean MORE rain, not less, for Hawaii….

Joe Public

Can’t they just pipe Arctic meltwater down to Hawaii. The UK’s Met Office predicts there’ll be surplusses, so it’ll be a win-win situation.

Jimbo

So, given their blunt admissions of uncertainty, I don’t even know why this press release exists – Anthony

Possible answer:

Funding:
The project was supported by grants from the U.S. Fish and Wildlife Service through the Pacific Island Climate Change Cooperative and the Pacific Islands Climate Science Center. Additional funding was provided jointly by the U.S. Army Corps of Engineers, Honolulu District, and the Commission on Water Resource Management, Hawaii Department of Land and Natural Resources.

And then we have a possible Viner moment:

……the scientists conclude that we can expect the recent trend towards drier winter seasons with fewer heavy-rain days to continue through the end of this century.

They and I won’t be around then so they can predict what they want.

DirkH

They are probably invested in a desalination plant builder. Are these the same guys that prescribed Australia its desal plants?

DirkH

AndyB says:
April 23, 2013 at 2:38 pm
“Has it always been this way with government funding for research or is this unique to climate research?”
I think politicians use scientists because the reputation of journalists is in the tank.
I wonder what they will use after scientists.

Jimbo

Sorry to post this again but it needs to be read regarding climate scientists and their batshit predictions / projections based on models and consensus.
http://notrickszone.com/2013/04/04/climate-science-humiliated-earlier-model-prognoses-of-warmer-winters-now-todays-laughingstocks/

Jimbo

It all hangs on this assumption:

Almost imperceptibly, rainfall over the Hawaiian Islands has been declining since 1978, and this trend is likely to continue with global warming through the end of this century,…..

The IPCC’s global mean temperature projections have failed in 2013. No worries, only 87 years to go. Winters were to be milder (now colder), the hotspot was supposed to be measured (now wind sheer crap) and so on…………What a bloody, hopeless failure. They think we are not looking.

Lewis P Buckingham

‘Almost imperceptibly’ Is this code for ‘outside the error bars’?
Just eyeballing the graph it looks cyclic over the short time frame of 30 years.
At least they did not make the Australian error of predicting eternal drought and empty dams.

What is a “cutting edge climate model”?
When modeled outputs are presented together they all cut badly, all exaggerate warming, drought, hurricanes, even mosquitoes!
They should use some money to invite Bob Tisdale to show them a few things that could possibly lead them to a better understanding of ENSO, and then maybe lead to longer forecasts than NOAA can do now.

“Hawaiians won’t know what rainfall is!”
Sounds very much like our UK weather outlook “Snow will be a very rare and exciting event!”
Not our last winter, nor the one before, nor the one before that either, in fact the one before that was even colder, and had more snow!
You can definitely rely on these alleged experts!

zootcadillac says:
April 23, 2013 at 2:04 pm
Nobody panic. We’ll just send them some of the snow we are inundated with every winter in the UK. That will cheer them up. Oh wait, perhaps I’m just imagining snow?
*
You’re not imagining it, Zoot, it’s just the wrong kind of snow (I don’t know why, maybe it doesn’t travel well in the mail). Heeheehee.

I have considerable first hand experience with rainfall in Hawaii – I was on Kauai for the duration of the 2003-04 flooding, provided material that protected several high profile properties from ending up in the ocean, and after the flooding of 2003-04 for a period I paid to maintain flood level monitoring equip on Kauai.
As others have noted the Hawaiian islands each exhibit the entire range of zones, from nearly tropical to almost desert. On Kauai this change occurs with 25 miles or so.
Precip varies on Kauai from appx 80″ annually on the Northeasterly windward side to less than 20″ on the westernmost leeward side. These numbers are however for the “makai” – or ocean front locations. A look at the “mauka” – or mountain locations – shows Kauai, in addition to have every type precipitation zone, also is home to the “wettest place on Earth – Mt. Wai’ale’ale – which has seen as much as 500+ inches of rainfall per year.
There are a couple other locations in the world that see slightly more total annual rainfall, however they are in monsoon zones, whereas Mt. Wai’ale’ale receives their rain largely year round.
There is plenty of water on Kauai, and on most of the Hawaiian islands, as each has similar trade wind dominated weather patterns and mountainous central cores. These trade winds (from the NE) blow over 80% of the time – with a thousands mile long fetch over open ocean. When they hit the islands the initial contact with land on the windward side starts squeezing moisture, thus the wetter North and East shores. But it is the core mountains that do the heavy work – wringing almost every last drop of moisture the trade winds bring – leaving the leeward areas of the island near desert-like.
The native Kauaian’s understood this, and as a result the island was divided into “ahupua’a” – land areas that went from a high elevation “mauka” water source (the Mt. Wai’ale’ale peak or adjacent Alaka’i swamp) to the makai (ocean) shore. Each ahupu’a provided access to fresh water source at higher elevation and to the ocean for sustenance.
This included, most importantly, the leeward areas of the, which, although they had very little rain themselves, were at thousands of feet lower elevation than Mt. Wai’ale’ale and the adjacent large Alaka’i Swamp.
So much water falls on Mt. Wai’ale’ale, that despite much of it running off in every direction, a large amount makes its way thru the Alakai Swamp and then into Waimea river, creating the spectacular Waimea canyon – known as the Grand Canyon of the Pacific. The Waimea rivers mouth at the ocean is the site of one of Captain Cook’s first landings in his discovery of the Sandwich Isles.
Native Hawaiian’s were excellent engineers as well as farmers. They diverted water from natural channels using sophisticated ‘auwai (water channels) to direct water, using gravity, to irrigate their “terrace” type crop production. They grew most taro – the Hawaiian’s most important crop – which provided many of their needs – food, medicine, bait, adhesive, dye, and other uses.
Water from the ‘auwai was diverted from the streams and rivers into the large taro ponds, called lo‘i kalo, and then channeled thru additional ‘auwai back to the stream.
Thus each ahupua’a provided its people all of their sustenance needs – fresh water, to drink and irrigate crops in the lower elevations with less rainfall, and access to the plentiful bounty of the ocean. Each ahupua’a also provided its people with a cool, higher elevation area for the short warm periods when the southerly Kona winds would blow (and cause thunderstorms and flooding).
Now to present – the historical data for 1949-2004 for Kauai:
http://www.wrcc.dri.edu/cgi-bin/cliGCStP.pl?hi6565
… show Mt. Wai’ale’ale averaging 373 inches per year. The highest year listed, at 429 inches occurred in 1951, and the lowest, at 283 inches just 2 years later in 1953.
As to current conditions – NOAA in their year end reports have noted”

2013 (March) Rainfall totals for most of the gages on Kauai have pushed up into the near average range for 2013 through the end of March. The USGS’ Mount Waialeale gage had the highest year-to-date total on Kauai at 82.07 inches (94 percent of average)

2012 – “Most of the rain gages on Kauai closed out 2012 with near average rainfall totals. Mount Waialeale received 326.44 inches (83 percent of average) which was the highest amount in the state.” NOAA shows the 30 year average in 2012 to be appx 393 inches per year.

2011 – Most of the gages on Kauai closed out 2011 with near to above normal rainfall totals. The Mount Waialeale total of 365.85 inches (93 percent of normal) was the state’s highest annual rainfall total and the highest annual total at this location since 2006

Three things are relatively certain about Hawaii’s precipitation. One, they have a lot of it, and aren’t about to run out any time soon – on Kauai between 300 and 500 inches a year at Mt. Wai’ale’ale.
Two, It is all but impossible to model or predict with any accuracy, the rainfall amounts in any of the Hawaiian islands. They are home to extremely unique and complicated weather dynamics – from the multiple climate/precip zones in close proximity, to things like the critical trade wind inversion layer (clouds cannot generally rise above it – appx 6,000 feet normally).
Three – despite having hundreds of inches of rainfall at the higher elevations each and every year, and despite the rainfall totals according to NOAA being at or near normal – each of the last several years, they have still managed to attribute drought status to large portions of each of the Hawaiian islands – the same areas that are normally the lowest precip areas.. Which qualifies for a federal disaster declaration and the release of funds for same. Imagine that.
http://hawaii.gov/dlnr/drought/
Link to Kauai rainfall map:
http://www.mykauairealty.com/website/agent_pictures/2839/kauai_rainfall_map_tki.JPG
Hawaiian Islands rainfall map:
http://www.darrensears.com/storage/hawaiian_precipitation_map.jpg
Kauai Ahupua’a areas:
http://islandbreath.org/2006Year/13-sovereignty/0613-03Kauaimoku.jpg
For those interested here is a link to an overview of Kauai’s history – well worth a read:
http://www.hawaiianencyclopedia.com/kauai-history.asp

sean

Forget about less rain, isn’t Hawaii predicted to drown under the same rising ocean that took Manhattan, as per Hansen, or does the sea only rise on one side of the continent????

That’s all very well and good. What if carbon dioxide were to cause; heavy snow and ice through winter, heavy rain, droughts and dry spells with floods, warm seasons and cold seasons. My question is, if I buy a lottery ticket for Saturday is there any chance that it will be mild and cloudy?

For those with more interest in why we see these extreme rainfall amounts in places like Kauai’s Mt. Waialeale – this paper is interesting:
Trade Wind Rainfall atop Mount Waialeale, Kauai Rimage & Schroeder (1999)
http://journals.ametsoc.org/doi/pdf/10.1175/1520-0493(1999)127%3C2217:TWRAMW%3E2.0.CO;2
This passage provides an example of the difficulty, due to the intricacies of the orographic effect, of predicting rainfall in Hawaii – but more importantly a simple, almost perfect, example of the problems with ALL climate models.
Here the researchers found that although the presence of trade winds was a critical component for strong rains due to the orographic uplifts, trade winds were NOT the instigator of these rain events. The trade winds required the “trigger” of existing cloudiness to cause the extreme rain effect.

Trade wind strength is linked positively to Waialeale rainfall, reflecting orographic uplift. That the correlation is smaller than expected, stems from the fact that although .50 mm fell on 26 days of fresh trade winds, ,6 mm fell on 17 other fresh trade wind days. As Siler (1962) said, ‘‘but topography alone is not the rain producing mechanism for it has been observed many times
that surface trades of approximately equal strength and direction do not produce rainfall totals of anywhere similar magnitudes.’’ Cloudiness is the differentiator. In the 26 wet days, cloudiness always exceeded 70%, while in the 17 dry days it was always less than 70%. This confirms the essential role of upwind cloudiness in the production of significant rain.

TRM

But they will still know what liquid sunshine is 🙂
When in Hawaii a few years back I was on the beach with my son and not a cloud in the sky. Perfect day in paradise. Then it starts to rain… with no clouds??? I thought it was a sprinkler on one of the hotel rooftops with the wind blowing it to the beach. A couple of days later I found out the wind can blow the rain over the mountains and it will hit the beach before the clouds get there. The locals call it “liquid sunshine”.

A. Scott says:
Ug! I am cave man, could it be the moon and the sun >>>CAVE ART…

Rosco

Why aren’t the actual rainfall figures shown.
Where I live – Sunshine Coast in Australia – we had significantly low rainfall during the 10 years preceding 2010.
But when the average is close to 2 metres per annum a 25% reduction is not that significant.
PS – the name “Sunshine Coast” is the most inappropriate locality name I know of. It has only recently stopped raining (with overcast skies replaced by blue) since early January. We have a beautiful autumn, winter on average.

James at 48

What a simplistic meme, the stuff of Sophomore lower division mumbo jumbo (which I know in my own case it certainly was). I get the concept – Horse Latitudes Highs do a “honey I blew up the High” act. But the nuanced view really does not support this. Warming (assuming it lasts much past our GHG and anthropogenic waste heat peak) should have a similar impact as past great warming events. The semi tropical dry zones shrink, the mid latitudes improve, the upper latitudes moderate slightly. Paleo proves this. Why would it be any different in the current case?

Craig Moore
lanny joe

I remember the spring og 1958–21 inches in 24 hrs

jorgekafkazar

“Almost imperceptibly, rainfall over the Hawaiian Islands has been declining since 1978, and this trend is likely to continue with global warming…”
Of course, the decline would be imperceptible: it’s not there. The rainfall curve doesn’t decline steadily; it rises and falls dramatically, clearly passing through vastly different regimes of natural variation, e.g., El Niño/La Niña cycles. There is a warming trend from 1985 to 1992, where precipitation increases, followed by an El Niño/La Niña dominated chaotic period from 1993 to 2004, then a plunge in precipitation as the Earth cools from 2005 to 2012. Trying to characterize all of these periods with an imaginary overall trend is just plain incompetent. The paper is drivel.