Tag Archives: severe weather

How Global Warming Causes Extreme Weather: New research

I want to tell you about what may be the most important research result in the area of climate change in recent years. First, a little background.

We know from paleoclimate studies that the Earth’s climate system changes from time to time enough to leave a mark. For example, it is widely thought that during the “ice ages” (periods of extensive or moderate glaciation) over the last couple of million years, areas that are currently very dry had a lot more water. Some combination of rain and evaporation (more rain and less evaporation) conspired to fill playas (dried up lakes) or salt lakes (like the Great Salt Lake in Utah) with so much fresh water that inland basins filled and started to drain out to the sea. It is hard to imagine how the weather would have been so different to make the arid regions of the American West into very wet places, long term, but it happened.

As we head towards a warmer and warmer planet, one would think that whatever happened during the ice ages would be the opposite of what we would expect in the future. To some extent that is almost certainly true, as certain regions will likely be much dryer in a heated up world than they were during the cooler ice ages. But some patterns of climate change are not simply characterized by temperature. The pattern of movement of air, and the pattern of moisture in the air, can be different from one climate system to another in very complex ways. Perhaps (this is very conjectural) the recent intense rains we see in the American West would be a common phenomenon in a warmed world. Perhaps the phenomenon of ARkStorm, a very rare situation where several “pineapple express” style storms happen over a single winter, large ones, in rapid sequence, filling the dry valleys of the American West with giant lakes and wiping out low lying villages and most of the crop land. That kind of feels like the Pleistocene when the great inland deserts were converted int great inland lakes! Or, perhaps the multe-year california drought that we experienced up until just a few months ago will become the “normal” situation.

Don’t get me started, but it is not difficult to imagine a world in which the American west has 4 to 10 year long droughts punctuated with a couple of winters in a row sufficiently wet to fill those lakes, so we get both!


ADDED: Jet Streams, Extreme Weather and Other Things with Stefan Rahmstorf


Here is the point of all this: Back in the 1950s through the early 1980s, by my estimation, North America (and probably many regions in the world) experienced stereotypical storm patterns that were like storm patterns seen over many centuries, though with the occasional interruption for something strage for a few years. 1860 – 1861 were strange years out west. The 1930s were strange in a lot of places. But what happened startomg around 1980 or so was different.

Prior to 1980s, storms in North America came from certain directions, were more common during certain times of years, dropped a range of precipitation amounts on the ground, and rarely were severe in the amount of rain that occurred. After 1980, the timing and various aspects of the physical nature of those storms including their apparent directionality and the speed which with they passed through, changed.

For example, in Minnesota, at the Twin Cities airport, there was an average of about 1.64 above 2 inch rainfall events per year for the hundred years of record keeping before 1971. In the time following, to the present, that number went up to about 2.7. Since about 2000 that number has gone to close to 3.5. Meanwhile, out east, the frequency of large blizzards has gone from one every few years to at least one in most years.

Putting this a slightly different way, the chance in a given year of having a major storm around these parts has more than doubled, with that doubling happening well within the lifetime of most of the people who live in the region.

I’ve written before about a special class of research on climate change that I have always regarded as among the most important. The authors of that earlier work overlap with the most recent work, with a key player being Stefan Rahmstorf. Rahmstorf and his colleagues, a few years ago, tackled an interesting problem that others had also noticed, and for which a number of explanations were floating around. Speaking of floating, this work surfaced and got some real traction when the Rocky Mountains near Boulder, and up near Calgary, were each hit by a really bad and very special kind of storm.

In each case, the storm system was trained along a very curvy and slow moving jet stream. When the jet stream slows it curves, or when it curves, it slows, or, really, kinda both. When that happens, if there is a big wet storm following along in the air system that itself creates/is created by the jet stream, that storm also slows. Fed by a more or less unending supply of moisture, such a storm can drop a lot of rain on a given region. We tend to think of the most severe storms as being fast moving, and they often are. Hurricanes can be pretty darn fast. Rapidly moving fronts coming off a dry line are associated with either tornado outbreaks or derecho storms. But these big and slow jet stream mediated storms are very very wet. Calgary was badly flooded, like no one has seen before. Boulder was very badly flooded more than in anyone’s memory.

Storms like this happen now and then, and can be found in historical records, and may have even happened in or near Calgary or Boulder at some time in the past. But since Calgary, we have had many many more such storms. Here in Minnesota, we’ve had a few. St. Louis had one. Texas had had a bunch of them. They’ve happened in China, Japan, all across Europe.

These storms, which are associated with a jet stream that is curvy and slow, are now common, and they were once rare.

What is the climate change connection? How do we know that global warming causes this?

There are a couple of different lines of evidence. First, as noted by the earlier work, and exemplified in the graph I put at the top of the post, which I made a couple of years ago, researchers have noticed that these curvy jet stream are more common. Another reason to think this is that curvy jet streams are expected to be associated with an Arctic that is warming more rapidly than the rest of the planet.

How does that work? I can explain it in general terms that will probably make some atmospheric scientists yell at me, but that I think is close to reality and also understandable by the average science-savvy civilian.

The big features of the weather system on a planet with an atmosphere have to do with heat reaching equilibrium across the planet. There is more heat near the equator, less near the poles, so it is all about heat moving from the equators to the poles, but also, hot stuff, water or air, making that journey. This hypothetically sets up an interesting phenomenon in the atmosphere that can be thought of as a giant twisting donut — a plain round donut shaped donut, not some hipster cream filled donut — just north of the equator, and another donut just south of it. Air is moving up in altitude at the equator, cools and spreads away from the equator, then drops back down to the surface, and heads back to where it was originally heated to get warmed up again.

This pair of giant twisting donuts of air helps set up another giant twisting donut of air to the north and south, and those donuts can, in turn, set up another, and so on. On a small planet like Mars, with a thin atmosphere, there may be one single donut per hemisphere. On giant heavy atmosphere planets like Jupiter and Saturn, you get many such donuts, and an overall striped appearance from a distance.

On earth, you get one really well defined donut (in each hemisphere) then a poorly defined donut, then another donut that is fairly well defined but that is also rotating in a circle, around the pole, much like a donut that got partly stepped on, rolled out the door of the donut shop, and his heading down the street.

Now here’s the thing, the explanation you can understand once you rap your head around these donuts: If the difference in heat at the equator vs. at the poles is great, the donuts are well defined and energetic. If the difference in heat between the equator and the poles is less, the donuts become less well defined, wobbly, and curvy.

The upper atmosphere region between adjoining donuts and the jet stream are more or less the same thing. So, as the arctic warms faster than the rest of the planet, the donuts change their configuration and you get curvy jet streams that can set up to remain in the same location over long periods of time.

Simple.

There was, however, a major missing part of this theory, and Michael Mann, climate scientist, joined the Rahmstorf et al team to fill in that blank. It is very difficult to be sure that a climatic phenomenon is either a) for real or b) characterizable as you’ve witnessed it, when you are looking at it for just a few years. If there is a change in climate because of the above described effects, there are not too many years of data allowing us to track it, observe its variations, or to figure out exactly how it works. This is complicated by several factors. For example, an alternate but similar explanation for the waves themselves, and the weather that comes with them, is the warming of the North Pacific. Hell, it could be both factors, because both factors may reduce the heat differential between the midriff and heads of the planet.

There are two obvious solutions to this problem. One is to sit back and wait a hundred years or so and collect data then consider the problem with a lot more information at hand. I’m sure climate scientists are busy doing this as we speak, but it may take a while! The other is to use climate modeling to simulate long periods of time, and see if quai-resonant waves and changes in the weather pattern are associated with anthropological global warming.

Michael Mann told me “that there is now a detectable influence of anthropogenic climate change on jet stream dynamics associated with extreme, persistent weather events like the 2010 Russian heat wave/wildfires, 2011 Texas heat wave/drought, 2013 European floods, etc. This is the first article, in my view, to demonstrate a robust such connection.”

This research involved combining some 50 climate models that comprise the CMIP5 project, and historical observations of climate over time. They found that under conditions of a warming Arctic, “standing waves” (quasi-resonant waves in other parlance) formed, just as we’ve seen during recent bad weather events. Above, I focused on rainfall events, but drought, extreme fire conditions, etc. are the other side of the coin, or rather, the other side of the jet streams. A persistent standing wave in a jet stream can cause a few nice and sunny days to transform into several years lack of rain, and a drought.

“Both the models and observations suggest this signal has only recently emerged from the background noise of natural variability. We are now able to connect the dots when it comes to human-caused global warming and an array of extreme recent weather events,” said Mann.

Here is the abstract of the paper:

Persistent episodes of extreme weather in the Northern Hemisphere summer have been shown to be associated with the presence of high-amplitude quasi-stationary atmospheric Rossby waves within a particular wavelength range (zonal wavenumber 6–8). The underlying mechanistic relationship involves the phenomenon of quasi-resonant amplification (QRA) of synoptic-scale waves with that wavenumber range becoming trapped within an effective mid-latitude atmospheric waveguide. Recent work suggests an increase in recent decades in the occurrence of QRA-favorable conditions and associated extreme weather, possibly linked to amplified Arctic warming and thus a climate change influence. Here, we isolate a specific fingerprint in the zonal mean surface temperature profile that is associated with QRA-favorable conditions. State-of-the-art (“CMIP5”) historical climate model simulations subject to anthropogenic forcing display an increase in the projection of this fingerprint that is mirrored in multiple observational surface temperature datasets. Both the models and observations suggest this signal has only recently emerged from the background noise of natural variability.

Historical data and cutting edge modeling and analysis strongly indicates that global warming, caused by human release of greenhouse gas, is increasing the frequency of persistent weather extremes such as very wet or very dry conditions. This paper looked at the northern hemisphere summer.

We have long passed the point where you can say with a straight face, “you can’t attribute a given weather event to global warming.” Climate change is change in climate; weather is climate today, climate is weather long term. Weather generally carries the climate change signal, and some of the weather is very different than it was prior to recent decades because of that change. You can’t separate a given weather event from global warming.

Michael E. Mann, Stefan Rahmstorf, Kai Kornhuber, Byron A. Steinman, Sonya K. Miller & Dim Coumou, 2017, Influence of Anthropogenic Climate Change on Planetary Wave Resonance and Extreme Weather Events.

Update: Super Typhoon Meranti Heads For Mainland China

Wed AM Update:

Meranti passed near the southern tip of Taiwan, and apparently it was pretty windy and nasty there. But, Taiwan has invested heavily in infrastructure with the idea of being hit with giant typhoons now and then, so things were not as bad as they could have been.

apparently Meranti is now a category 5 equivalent heading for China. The storm is expected to weaken only a bit as it makes landfall (see this post on what landfall means) so this is going to be a direct hit by a major hurricane. There are some pretty densely populated areas in the storm’s path. There are also many harbors that narrow quickly on the way into the elevated interior, where there is a very hilly terrain and some moderately restricted inland valleys. So, the prospects for major storm surges and serious inland flooding are significant.

Original Post:
typhoon_meranti_taiwan_china
Within a 24 hour time period, Typhoon Meranti cranked up from what we in the US would call a Category 1 storm to a Category 5 storm. Or stronger, if we had more categories.

Some time between late Tuesday and mid day Wednesday, the typhoon will have a run at the southern tip of Taiwan. This is the less populated part of the island, but this is a big storm and its effects will be felt over the entire country.

wp201616_5day

Interacting with Taiwan is not expected to slow down the storm too much, and some time late Thursday, possibly as a Category 3 equivalent, it will slam into China.

Then it will go inland and contribute significantly to flooding.

This is the strongest cyclone so far in this year’s Northern Hemisphere season. Under climate change, we expect some cyclones to undergo much more rapid intensification, which can be a real problem when it occurs just before making landfall. This is the case with Meranti, though, as noted, the area to be affected initially is not as dense of a population zone as it might have been. The storm is stronger than it otherwise would have been had it not been for global warming, as well.

For a further discussion of human caused global warming and this storm, visit Climate Signals (Beta). The graphs above are from Weather Underground.

Tropical Storm Ian Not Likely To Be Interesting

Update: Mid Day Monday:

Ian is no longer a glimmer in the eyes of NWS forecasters. Ian is now a tropical storm. However, Ian is about to head north over unfavorable waters, will likely never develop hurricane strength, and is not expected to hit anything big. (See map above.)

Nothing else is really happening in the Atlantic at this time, wrt storms. There is a disturbance in the Lesser Antilles, which is not likely to do anything more any time soon, if at all.

Update: Monday AM:

Yes, the chances that a tropical storm that has been tracked for a few days now as a disturbance will form today is very high. By the end of the day we may have a named storm, and that storm may be Ian.

Here is incipient Ian:
two_atl_2d1

Original Post:

The Atlantic Ocean is certainly having a special day today, with three, count ’em, three areas of disturbance spread across a huge area:

screen-shot-2016-09-10-at-10-07-03-am

The one on the right has a very high probability of turning into something real, perhaps eventually to be a named storm, some time over the next few days. It is way too early to say much more than that about it.

But, since the topic of storms has come up, check out the latest video by Peter Sinclair on the topic of weather and anthropogenic global warming:

The Changing Climate of Atlantic Storms and How The Are Reported

Hurricanes are well defined systems with characteristics that quite literally set them apart from other storms. Large storms such as Nor’Easters are sometimes less well defined and interact more with major troughs, the jet streams, etc. We have come to understand Hurricanes as the worst case scenario, while other storms are less dangerous.

But sometimes, and I suspect more recently lately, these non-tropical storms become quite dangerous. The Great Storm of ’78 killed hundreds in New England and made us suddenly realize that coastal property was a temporary thing. But we sense the danger of recent storms less acutely because for all storms we have better warning systems, and most storms don’t kill that many people these days, like they used to. So worse storms seem less bad.

And sometimes, it turns out that these large powerful and dangerous extratropical systems and the tropical hurricanes or their remnants merge and interact, creating what sometimes emerges as a “superstorm” or at least, a “really inconvenient storm.”

Sandy is an example of the former. Perhaps Hermine is an example of the latter. Hopefully not the former as well!

The focus on hurricanes as the dangerous big brother of temperate storms (including Nor’Easters) has unintentionally shaped our storm warning system to downplay by default non-hurricane storms, including the hurricanes themselves when they become extratropical. But the “remnants” of hurricanes over land are usually very dangerous because of the flooding they cause, and late in life former hurricanes are capable of ganging up with temperate systems to become very dangerous.

In the case of Superstorm Sandy, owing to global warming driven warm waters, the storm remained as a hurricane at the time it started to interact with temperate storm systems, and the result was one of the worst storms to hit the US East Coast. Yet, it was technically not a hurricane at landfall. Rather, it was a hurricane that ate another storm on its way to Ohio, and got too big, too powerful, too messy, and too dangerous to maintain use of the term (hurricane) normally reserved for better organized, more predictable, and better behaved dangerous storms.

Maybe we are seeing a shift in where the danger lies in Atlantic storms. There will never be a storm as dangerous as a Major Hurricane moving just the right way at just the right time against just the right piece of coastline. Ivan, Andrew, Katrina, like that. But the typical Category I hurricanes and the seemingly new phenomenon of more frequent post-tropical hybrids, and more frequent certain supercharged Nor’Easters seem all in about the same category of overall badness.

We are certainly seeing some self reflection on the part of meteorologists, who are always faced with the very difficult task of properly informing and educating the public, properly modulating alarm over a given storm system, always trying to not cause problems for the next storm by overstating or understating expectations. Some of this self reflection, as well as the gory details of how these different kinds of storms (Nor’Easter or Hurricane-Extratropical hybrid) develop is demonstrated in the following passages taken from various Hurricane Center discussions or Wikipedia, pertaining to the storms as indicated. I put them here for your enjoyment and/or horror.

1991 Perfect Storm

The 1991 Perfect Storm, also known as the The No-Name Storm (especially in the years immediately after it took place) and the Halloween Gale, was a nor’easter that absorbed Hurricane Grace and ultimately evolved back into a small unnamed hurricane late in its life cycle. The initial area of low pressure developed off Atlantic Canada on October 29. Forced southward by a ridge to its north, it reached its peak intensity as a large and powerful cyclone. The storm lashed the east coast of the United States with high waves and coastal flooding before turning to the southwest and weakening. Moving over warmer waters, the system transitioned into a subtropical cyclone before becoming a tropical storm. It executed a loop off the Mid-Atlantic states and turned toward the northeast. On November 1 the system evolved into a full-fledged hurricane with peak winds of 75 miles per hour (120 km/h), although the National Hurricane Center left it unnamed to avoid confusion amid media interest in the predecessor extratropical storm. It later received the name “the Perfect Storm” (playing off the common expression) after a conversation between Boston National Weather Service forecaster Robert Case and author Sebastian Junger. The system was the fourth hurricane and final tropical cyclone in the 1991 Atlantic hurricane season.

Hurricane and Superstorm Sandy

FIRST A NOTE ON THE NWS WARNING STRATEGY FOR SANDY. IN ORDER TO
AVOID THE RISK OF A HIGHLY DISRUPTIVE CHANGE FROM TROPICAL TO
NON-TROPICAL WARNINGS WHEN SANDY BECOMES POST-TROPICAL…THE WIND
HAZARD NORTH OF THE TROPICAL STORM WARNING AREA WILL CONTINUE TO BE
CONVEYED THROUGH HIGH WIND WATCHES AND WARNINGS WARNINGS ISSUED BY
LOCAL NATIONAL WEATHER SERVICE OFFICES.

SANDY CONTINUES TO MAINTAIN AN AREA OF DEEP CONVECTION NEAR THE
CENTER…WITH AN EYE OCCASIONALLY VISIBLE ON SATELLITE IMAGERY.
ALTHOUGH THE SATELLITE PRESENTATION OF THE SYSTEM IS NOT VERY
IMPRESSIVE…SFMR MEASUREMENTS…FLIGHT-LEVEL WINDS…AND DROPSONDE
DATA FROM THE AIR FORCE HURRICANE HUNTERS INDICATE THAT THE WINDS
HAVE INCREASED TO NEAR 75 KT. SINCE THE HURRICANE WILL TRAVERSE
THE GULF STREAM THIS MORNING…AND THE SHEAR IS NOT TOO STRONG AT
THIS TIME…SOME MORE STRENGTHENING AS A TROPICAL CYCLONE IS
POSSIBLE IN THE NEXT FEW HOURS. HOWEVER…THE MAIN MECHANISM
FOR INTENSIFICATION LATER TODAY SHOULD BE BAROCLINIC FORCING. THE
OFFICIAL WIND SPEED FORECAST IS CLOSE TO THE LATEST GFS PREDICTION
AS THAT MODEL SHOULD BE ABLE TO HANDLE THE EVOLUTION OF THIS TYPE
OF SYSTEM FAIRLY WELL.

THE CONVECTIVE STRUCTURE OF SANDY HAS DETERIORATED TODAY…EVEN AS
THE CENTRAL PRESSURE HAS CONTINUED TO SLOWLY FALL…SUGGESTING THAT
THE CONVECTION IS NO LONGER DRIVING THE BUS. THE INTENSIFICATION
OBSERVED THIS MORNING WAS ASSOCIATED WITH STRONG WINDS OCCURRING TO
THE SOUTHWEST OF THE CENTER…OUTSIDE OF THE CENTRAL CORE…AND WAS
ALMOST CERTAINLY DUE TO BAROCLINIC FORCING.

SATELLITE…RADAR…SURFACE…AND RECONNAISSANCE AIRCRAFT DATA
INDICATE THAT SANDY MADE LANDFALL NEAR ATLANTIC CITY NEW JERSEY
AROUND 0000 UTC. THE INTENSITY OF THE POST-TROPICAL CYCLONE WAS
ESTIMATED TO BE NEAR 80 KT AT LANDFALL WITH A MINIMUM PRESSURE OF
946 MB. AT LANDFALL…THE STRONGEST WINDS WERE OCCURRING OVER
WATER TO THE EAST AND SOUTHEAST OF THE CENTER. HURRICANE-FORCE
WINDS GUSTS HAVE BEEN REPORTED ACROSS LONG ISLAND AND THE NEW YORK
METROPOLITAN AREA THIS EVENING. IN ADDITION…A SIGNIFICANT STORM
SURGE HAS OCCURRED ALONG A LONG STRETCH OF THE MID-ATLANTIC AND
SOUTHERN NEW ENGLAND COAST.

2016 Hermine

Satellite imagery indicates that Hermine has become a post-tropical
cyclone, with the coldest convective tops now located more than 200
n mi northeast of the exposed center. Despite this change in
structure, surface data from the Outer Banks indicate that some
strong winds persist near the center, and the initial intensity is
set to 55 kt for this advisory. During the next 48 to 72 hours,
Hermine will interact with a strong mid-latitude shortwave trough
and all of the global models show the system re-intensifying during
that time and a redevelopment of a stronger inner core, albeit one
situated underneath an upper-level low. Regardless of its final
structure, Hermine is expected to remain a dangerous cyclone through
the 5 day period.

Hermine more serene?

Update (Sunday PM):

Hermine is still a big storm and will affect eastern regions to some degree, but the storm never reformed as a hurricane, and is not not expected to do so. Also, the storm has jinked out to the east more than expected and will likely move farther east. So, there will be some coastal effects, but not much out of the ordinary.

POST-TROPICAL CYCLONE HERMINE FORECAST/ADVISORY NUMBER 30
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092016
2100 UTC SUN SEP 04 2016

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY…

A TROPICAL STORM WARNING HAS BEEN ISSUED FROM WATCH HILL…RHODE
ISLAND EASTWARD TO SAGAMORE BEACH…MASSACHUSETTS INCLUDING BLOCK
ISLAND…MARTHA’S VINEYARD…AND NANTUCKET.

THE TROPICAL STORM WARNING HAS BEEN DISCONTINUED FROM FENWICK
ISLAND…DELAWARE SOUTHWARD…AND ALSO DISCONTINUED FOR DELAWARE
BAY NORTH OF SLAUGHTER BEACH.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT…

A TROPICAL STORM WARNING IS IN EFFECT FOR…
* NORTH OF FENWICK ISLAND TO SAGAMORE BEACH
* DELAWARE BAY SOUTH OF SLAUGHTER BEACH
* BLOCK ISLAND
* MARTHA’S VINEYARD
* NANTUCKET

Original Post:

Hermine was bad enough for florida, though of course, nothing like a Major Hurricane. But, the downgraded storm may not be done with us yet. There is a very good chance that Hermine will reform into a hurricane, or at least something that we’ll call a hurricane because it will look like a hurricane, blow like a hurricane, and hurt like a hurricane, over the next several hours. This will happen after the land-damaged storm passes over global warming heated ocean waters. Sometime between mid day and early evening on Saturday, Hermine could gain hurricane strength and directly affect New Jersey and nearby places.

Barrier islands from the Carolinas to New Jersey, but especially around Delmarva, New Jersey, and New York, are at risk for storm surges, with a major risk in southern Delmarva and Virginia Beach, and the lower Tidewater. Outer New Jersey may experience something like a 6 foot storm surge Sunday night or early Monday AM.

This is Labor Day Weekend. A very large number of people go to these areas over this Final Weekend before the perceived end of summer. Causeway roads that connect these barrier islands to the mainland may be washed out, and the barrier islands themselves are not great places to be.

The big question at hand is this: Will the state authorities in these areas have the will and the wiles to warn their citizens and visitors off these dangerous areas, or will they avoid damaging business by sitting on their hands. Then, either way — whether a particular area is damaged by the storm or damaged by safety in light of the storm — will there be some help for those businesses? Oh, and lets not forget to include these considerations in the costs of this storm.

So be careful, watch the weather, and pay attention, if you live anywhere on the US East Coast.

Hawaii Hurricanes: Madeline and Lester? Or Neither?

Update (Noonish Friday):

Lester is going to skim along to the north of the Hawaiian Islands. This is an estimate of the probability of the distribution of 50mph winds:

Screen Shot 2016-09-02 at 11.58.54 AM

Surf’s up, it will be stormy, but the significant threat is moderate.

Update (Noonish Thursday):

Madeline sort of hit Hawaii, but it also did a funny little shrug as the medial to outer bands got close to the big island, and the rematerialized on the other side, keeping with the mysterious tradition (see below) of hurricanes magical avoiding the island state. But, the storm surge did in fact swamp a lot of places along the coast and it is a bit of a mess there.

Meanwhile, Hurricane Lester is still pointed roughly at the island, but likely to pass to the north, still affecting but not directly landing on Hawaii. But, these storm tracks can change, so stay tuned.

Original Post:

Hawaii is tiny. And huge. Look:

Islands-of-Hawaii-vs-US

Hawaii is larger in land area than Rhode Island, Delaware, or Connecticut, but smaller than all the other states. The big island is a bit larger in land area than all the other islands put together. Yes, the entirety of Hawaii covers a huge area of the Pacific. The longest linear dimension of the state of Hawaii is longer than the longest linear dimension of any US state, and of most countries. This is a property of many Pacific polities, including most Pacific island nations.

Yet, even though Hawaii, located in the Pacific tropics, should be a virtual catcher’s mitt for cyclones (hurricanes), the big island has hardly ever been hit directly by anything. Hawaii as a state is often affected by tropical storms, but usually in the form of surf (and Hawaii is where they invented surfing, so that is mostly a good thing). Is this simply because Hawaii is big (east-west wise) yet small (north-south wise) and thus is simply very lucky?

Or, is Hawaii located in an area that major tropical cyclones tend to go around, or at least, not through. Like this:

Tracks_of_Central_Pacific_Hurricanes_1949_to_1998

From Wikipedia:

Hawaii’s apparent immunity to most hurricanes

The islands of Hawaii, with Kauai as the notable exception, appear to be remarkably immune from direct hurricane hits. The USGS states that “more commonly, near-misses that generate large swell and moderately high winds causing varying degrees of damage are the hallmark of hurricanes passing close to the islands.”[31] This has also drawn media attention.[32][33] One notion is that Hawaii’s volcanic peaks slow down or divert storms.[34] A partial source of this idea may be the long list of hurricanes … that dissipated into tropical storms or depressions upon approaching the islands. Satellite images of Hurricane Flossie’s breakup when approaching Hawaii Island fueled this idea.[35] Another example may be Hurricane Felicia which dropped from Category 4 down to a tropical depression with residual winds predicted at only 35 miles per hour (56 km/h).[36]

Tropical Storm Flossie (not to be confused with Hurricane Flossie in 2007) provides still another example. On July 28, 2013, the storm appeared headed for a direct hit to the Big Island, home to Mauna Kea and Mauna Loa. Both mountains rise to elevations in excess of 13,000 feet above sea level, and as Flossie approached the island, its track shifted abruptly overnight and assumed a more northerly alignment, heading instead to the island of Maui on July 29.[37]

Wind data in particular supports the USGS assertion that hurricane damage has been low on all islands except for Kauai. Data collected by the Western Regional Climate Center show no hurricane-strength winds on any Hawaii Islands with the exception of Kauai.[38] Despite this data, FEMA classified all of Hawaii as being in a “Wind-Borne Debris Region”.[39][40][41]

Before Hurricane Iniki in 1992, a standard homeowner’s insurance policy with extended coverage provided hurricane coverage. Since Iniki, many insurance policies exclude hurricane and a separate hurricane policy is required to obtain hurricane coverage.

At present, Hawaii, in particular the big island, is threatened with a tropical cyclone, likely to be a full on hurricane. Will it hit? Will it magically turn away from the island state?

Hurricane Madeline is weakening but at the same time heading for the big island, and should start affecting the island over the next day or two. This chart from Weather Underground lays out the expected timing:

map_tropprjpath14_ltst_5nhpao_enus_650x366

But wait, there’s more. Hurricane Lester is also in the area and is heading for Hawaii as well. This would happen some time over the labor day weekend. Lester has less of a chance of being a full blown Hurricane when hitting Hawaii than Madeline, but it is way to early to be certain of much.

If two hurricanes hit Hawaii over the next several days, that would be rather amazing. If one hits Hawaii over the next several days that would notable. If both Hurricanes magically turn their course or dissipate before hitting Hawaii during the next several days, that will be data. Very interesting data!

Super Typhoon Nepartak

This is a huge hurricane/typhoon heading quickly, and imminently, towards taiwan.

The storm itself is roughly as wide as the island nation is long, so very little will be left unaffected.

The storm is at the very high end of the range of storms in size, strength, etc. It is currently equivalent to a Category 5 hurricane. It may weaken a bit before landfall over the next few hours, but it may remain a Category 5.

Winds, huge waves and coastal flooding from storm surges will be a big problem with this storm, but the largest problem may be the incredibly high rainfall, with about one meter of rain (3 feet) predicted in some locations. This could cause unprecedented and major flooding.

Nepartak should be regarded as a global warming enhanced storm. The storm is made so large and strong because of extraordinarily high sea surface temperatures, which in turn is an effect of human caused global warming.

Locally, the Green Island and the Taiwanese city of Taitung City are on or very close to the expected storm track. If the storm tracks a bit south, expect very severe storm surges in Taitun city. Either way, there will be major rainfall in the river basins, and the valley ousee north of Taitung City, which has several settlements in it, seems likely to be at major risk.

Screen Shot 2016-07-07 at 10.31.03 AM

Here is the most current (10:34 AM CT) map from Weather Underground showing the relationship between the storm and Taiwan.

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Climate Signals has info on the storm, and does a good job at evaluating the likely relationship between the storm and human caused climate change.

On July 4 and 5, in just 24 hours, cyclone Nepartak intensified from a 70 mph storm to a Category 4 super typhoon with 150 mph winds, peaking with 1-minute sustained winds of 173 mph (150 knots) on July 6. Currently a Category 5 storm, Nepartak is forecast to strike Taiwan Thursday night, July 7, local time (midday Eastern time) before moving on to eastern China. The rapid intensification of Nepartak was driven by favorable climate conditions, including passage over unusually warm seas with some of the highest oceanic heat content readings observed in conjunction with a tropical cyclone. There is a documented increase in the intensity of the strongest storms in several ocean basins in recent decades, including the Pacific Northwest. And warming seas are offering more energy to passing storms. Extreme rainfall over Taiwan is expected to be intense, fueled in part by a warmer atmosphere, with total rainfall in some areas reaching well above 3 feet. The reach of Nepartak’s storm surge will be extended due to elevated sea levels driven up by global warming.

Jeff Masters is covering the storm here. He discusses the very rapid development of this storm:

Category 5 Super Typhoon Nepartak is steaming towards a Thursday landfall in Taiwan after putting on a phenomenal display of rapid intensification on Monday and Tuesday. Nepartak went from a tropical storm with 70 mph winds on Monday afternoon to a Category 4 super typhoon with 150 mph winds on Tuesday afternoon, in just 24 hours.

Climate Signals: Excellent new resource

Weather is climate here and now, and climate is weather over the long term. Climate is the large scale process of movement of air and water, and changes in the properties of air and water, on and near the surface of the Earth, the atmosphere, oceans, and ice fields respond to the imbalance of heat — with more of it near the equator and less of it at the poles — as the world literally turns. Weather is the local, temporal, and personally observable sign of that climate system. Climate is meaning and weather is the semiotic process by which we understand that meaning.

OK, perhaps I’ve gone too far with the semiotics.

Anyway, I’m pretty sure that the number one way in which change in the climate system, that change caused over several decades of release of greenhouse gasses (and other changes) by humans, is understood by people is through the observation and experience of weather. All the data from NOAA and other earth-watching science agencies, all those excellent blog posts about this or that piece of research, all the great talks by the top climate scientists don’t amount to a hill of beans when compared to a long lasting killer heat wave, a devastating hurricane, a swarm of town-smashing tornadoes, or a vast flooding event. Not so much one event, but the obvious and undeniable increase in frequency of such events.

Climate Signals is one of those great ideas that addresses a basic need using a compelling approach. Climate Signals, currently in Beta form, is a data base of climate events, with geographical information, and highly structured information linking these events to research, indicating climate change connections with varying degrees of certainty, news reports, and all the other information one might want about those events.

I believe Climate Signals will become a significant go-to source for journalists writing about climate, as well as policy makers and even scientists who want to make reference to specific events and get those references right.

Climate change affects us all. Through the use of mapping, Climate Signals shows what climate change looks like on the ground, in your region, state, or neighborhood and identifies the long-term climate trends and physical processes that may be at work.

You should go to the Climate Signals website and browse around. Give them feedback. Send the link to friends and foes. I’m going to make it part of my daily reading.

Atlantic Tropical Cyclone Colin

Update Monday June 6 AM: TropicalStorm Colin is heading for Florida.

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The disturbance first noted a few days ago east of the Yucatan has moved across the mainland, into the eastern Gulf of Mexico, and with the relatively warm sea surfaces there as a source of inspiration, turned into Colin, a tropical storm.

Colin is not expected to become a hurricane, but it will make landfall somewhere on the Florida coast between, roughly, between Tallahassee and Tampa, tonight (Monday). The center of the current forecast is somewhere near Fish Creek and Steinhatchee, but that may change and this will be a large, wide, wet and windy blob.

The storm will cross the base of the florida peninsula and come out to the Atlantic late Tuesday or Tuesday night, somewhere near the Georgia/Florida state line, where it will affect coastal regions in the Atlantic. The storm will then head north up the Atlantic and dissipate.

It is possible the storm will actually be its strongest after it has crossed land and is over the warm near coastal Atlantic waters, where sustained winds may be about 60 mph.

It is very rare to have three named storms by the end of the first week of the hurricane season, but note that the first named storm actually occurred nearer to the end of the 2015 season but was tacked on to this year’s season for some reason.

But, it is also interesting to note that having two named storms by the end of the first week of the hurricane season is still fairly rare. So, perhaps this is going to be an interesting hurricane season after all!

Original:

It is way to early to be sure, but there is a better than even chance that a tropical disturbance in the Atlantic near the Yucatan will develop over the weekend and subsequent days into something namable, and if so, it will be named Colin.

This weather system will likely cross the Yucatan over the next couple of days, and then, when in the Eastern Gulf of Mexico, gain some strength and turn into something.

Even if the system does not become a tropical storm of some sort, it will make parts of Mexico, Cuba and Florida wet.

An Evangelical Christian Republican View of Climate Change

Trending wetter with time: weather never moves in a straight line, but data from NOAA NCDC shows a steady increase in the percentage of the USA experiencing extreme 1-day rainfall amounts since the first half of the 20th century. Photograph: NOAA NCDC

My Apology to Paul Douglas

I admit that I do a lot of Republican bashing. I’m a Democrat, and more than that, I’m a partisan. I understand that a political party is a tool for grass roots influence on policy, if you care to use it. The Democratic party platform, at the state and national level, reflects my policy-related values reasonably well, and the Republican approach is largely defined as supporting the opposite of whatever the Democrats say, even when Democrats come up with a policy that is closely based on a previously developed Republican policy. So, my hope is to see the Democratic caucus in the majority, in both houses of my state legislature, and both houses of the US Congress. And a Democratic President. This is the only way that the policies I see as appropriate and important are advanced, and the anti-policies put forth by the reactionary party, the Republicans, are not.

So, with respect to elected officials, I will always oppose Republicans and always support Democrats. That includes opposing “Reasonable Republicans” (an endangered species) and, not happily, supporting Red Dog Democrats. This is necessary because of the necessity of a majority caucus in each legislative branch. (You probably know this, but the majority party gets to call the shots, run committees, etc.) At some future date, when Democratic majorities are not as tenuous, I may change that approach, but not now.

If key policy orientations for key issues tended to find cross-party support, I would not be so much of a partisan. But that is not what happens these days in government. My partisanship is not a choice, but a necessity required by Republican reactionary philosophy among elected officials.

So, that is my explanation — not excuse, but explanation — for my Republican bashing, a behavior that is one side of a coin. The obverse is, obviously, Democratic cheerleading.

And, with that as background, I sincerely apologize to my friend Paul Douglas.

Minnesota Nice Weather

Paul is one of the country’s top meteorologists.

When I was about to move to Minnesota, I flew out to find an apartment for my family, and get the feel of the landscape. I stayed in a hotel in the near western suburbs, and spent each day looking at apartments, and checking out driving times between various neighborhoods and the University of Minnesota. Every evening I pick up the local papers to peruse them while watching the local news, because that is a good way to get to know a place.

One day I was out driving around, lost, somewhere near downtown on this mess of highway that made no sense to me. The sky had been filled since early morning with enormous thunderheads, the kind I had seen previously in the Congo, but rare in Boston, where I was living at the time. Suddenly, a huge thunderstorm passed overhead, with hail, and the road filled with water, forcing me to pull off for a few minutes to avoid hydroplaning. After the storm had passed, I drove back out onto the highway, and witnessed an amazing sight.

First, I should note that in Minnesota, you can see the sky for great distances because it is relatively flat here. Minnesotans don’t think of Minnesota as flat, and compared to Kansas, it isn’t. But it is compared to my previous homes in Boston or upstate New York. I remember thinking that day that Minnesota counted as “Big Sky Country” in its own way. Minus the Rocky Mountains.

Anyway, the sky was being big, and the view was filled with more thunderheads. But off to the northeast was a huge horizontally elongated cloud. It was at about the same elevation as the lower parts of the nearby thunder clouds, longer in its longest dimension than a good size thunder storm, but shaped more like a giant cigar. And it was rotating, rapidly, like a log rolling down hill. (Except it wasn’t really going anywhere.)

I thought to myself, “This is amazing. I wonder if the people of Minnesota appreciate how spectacular and beautiful is their sky and weather, which they observed every day!”

Later that evening, I got back to my motel and switched on the news. The top news story that day, it turns out, happened to be the day’s thunderstorms, so the anchor handed off the mic to the meteorologist.

I had made an error in thinking that the people of Minnesota might be inured to spectacular thunder storms and giant rotating cigar shaped clouds. The weather reporter was showing news footing of the sky, including the rotating cigar shaped cloud I had witnessed. He told the viewers that the storms today were especially spectacular, and that this giant rotating cigar thing was a special, highly unusual weather event. He named it, calling it an arcus cloud, and noted that it was effectively similar to a tornado, in terms of wind speed and destructive potential, but that this sort of cloud rarely touched down anywhere.

(This sort of arcus cloud is a roll cloud, very rare in continental interiors, though somewhat more common in coastal areas.)

That year there were many thunderstorms in the Twin Cities. The following year as well. There were also a lot of tornadoes. All of the tornadoes I’ve ever seen with my own eyes (small ones only) were during that two year period, including one that passed directly overhead and eventually damaged a tree on the property of a house we had just made an offer on, subsequently moving along a bit father and menacing my daughter’s daycare.

An Albino Unicorn Observes Weather Whiplash

I’m pretty sure, if memory serves, that some time between my observation of the arcus cloud and the Saint Peter tornado, Paul Douglas moved from Chicago back to the Twin Cities, where he had perviously been reporting the weather.

Paul Douglas will tell you that during this period he, as a meteorologist covering the midwest and plains, started to notice severe weather coming on more frequently than before. When such a thing happens a few years in a row, one can write that off as a combination of long term oscillations in weather patterns and random chance. But when the fundamental nature of the weather in a region shifts and such normally rare events become typical, then one might seek other explanations. Climate change, caused by the human release of greenhouse gasses into the atmosphere, is ultimately the explanation one is forced to land on when considering widespread, global (and Minnesotan), changes in weather patterns.

Paul describes himself as an “albino unicorn.” This is not a reference to a horn sticking out of his nose, or atypical pigmentation. Rather, he recognizes that as a Republican who fully accepts science, and in particular, the science of climate change, he is an odd beast. It is worth noting that Paul is also an Evangelical Christian. There are not many Evangelical Christian Republicans who understand and accept science. There are probably more than the average liberal or progressive Democrat thinks there are, because such rare beasts need to keep their heads down in many contexts. But Paul is the rarer subspecies of albino unicorn that simply refuses to do that. He speaks openly and often about climate change, giving talks, frequent interviews (like this one with me), and regular appearances on various news and commentary shows.

Paul currently runs this company, and writes an excellent weather blog here. His weather blog focuses on Minnesota weather, but it should be of interest to everyone in the US and beyond, because he also catalogues current extreme weather events globally, and summarizes current scientific research on climate change.

You are probably familiar with The Guardian’s blog on climate change, “Climate Consensus – the 97%” written by my fellow Minnesotan John Abraham, and Dana Nuccitelli, author of Climatology versus Pseudoscience: Exposing the Failed Predictions of Global Warming Skeptics. The current post on that blog is a guest post by Paul Douglas: Meteorologists are seeing global warming’s effect on the weather.

The graph at the top of this post is featured in Paul’s writeup, so go there and read the background. If you happen to know Donald Trump, suggest to him that there is an interesting write-up on climate change by an Evangelical Christian Republican, which he should read in order to get the Evangelical Christian Republican view on the topic!

Paul writes:

In a day and age of scammers, hackers, hucksters and special interests it’s good to be skeptical. You should be skeptical about everything. Some of the biggest skeptics on the planet are scientists. In fact, science is organized skepticism. Climate and weather are flip-sides of the same coin; everything is interconnected. Climate scientists tell us the climate is warming and meteorologists are tracking the symptoms: freakish weather showing up with unsettling regularity. Even if you don’t believe the climate scientists or your local meteorologist do yourself and your kids a favor. Believe your own eyes.

Paul saw the signature of anthropogenic climate change in the weather he was analyzing and reporting on long before climate scientists began to connect the dots with their research. Many of the dots remain unconnected, but the association between observable changes in the climate system and changes in the weather is now understood well enough to say that it is real. I believe that the recent uptick in acceptance of climate science by Americans is partly a result of the impossible to ignore increase in severe weather events, especially flooding and major storms. The most severe heat waves have, so far, occurred in other countries, but we do get the news and we do know about them.

Check out Pauls’ Guardian writeup where he connects the dots for you, and makes a strong case that we need to put aside denialism of the science.