Hawaiian Islands weather details & Aloha paragraphs / March 2-3, 2010

March 2-3, 2010

Air Temperatures – The following maximum temperatures were recorded across the state of Hawaii Tuesday afternoon:

Lihue, Kauai – 78
Honolulu, Oahu – 81
Kaneohe, Oahu – 78
Kaunakakai, Molokai – 78
Kahului, Maui – 79
Hilo, Hawaii – 80
Kailua-kona – 85

Air Temperatures ranged between these warmest and coolest spots near sea level around the state – and on the highest mountains…at 4pm Tuesday afternoon:

Kailua-kona, Big Island – 85F
Kapalua, Maui – 73

Haleakala Crater –    48 (near 10,000 feet on Maui)
Mauna Kea summit – 34 (near 14,000 feet on the Big Island)

Precipitation Totals – The following numbers represent the largest precipitation totals (inches) during the last 24 hours on each of the major islands, as of Tuesday afternoon:

0.22 Mount Waialaele, Kauai  
0.18 St. Stephens, Oahu
0.00 Molokai 
0.00 Lanai
0.00 Kahoolawe
0.10 West Wailuaiki, Maui 
1.03 Kawainui Stream, Big Island

Marine Winds – Here’s the latest (automatically updated) weather map showing a 1032 millibar high pressure system to the north-northwest of Hawaii. This high pressure system, and its associated ridge, will keep strong and gusty winds in place through Wednesday…a bit lighter Thursday.

Satellite and Radar Images: To view the cloud conditions we have here in Hawaii, please use the following satellite links, starting off with this Infrared Satellite Image of the islands to see all the clouds around the state during the day and night. This next image is one that gives close images of the islands only during the daytime hours, and is referred to as a Close-up visible image. This next image shows a larger view of the Pacific…giving perspective to the wider ranging cloud patterns in the Pacific Ocean. Finally, here’s a Looping IR satellite image, making viewable the clouds around the islands 24 hours a day. To help you keep track of where any showers may be around the islands, here’s the latest animated radar image.

Hawaii’s Mountains – Here’s a link to the live webcam on the summit of near 14,000 foot Mauna Kea on the Big Island of Hawaii. The tallest peak on the island of Maui is the Haleakala Crater, which is near 10,000 feet in elevation. These two webcams are available during the daylight hours here in the islands…and when there’s a big moon rising just after sunset for an hour or two! Plus, during the nights and early mornings you will be able to see stars, and the sunrise too…depending upon weather conditions.

Tropical Cyclone activity in the eastern and central Pacific – Here’s the latest weather information coming out of the National Hurricane Center, covering the eastern north Pacific. You can find the latest tropical cyclone information for the central north Pacific (where Hawaii is located) by clicking on this link to the Central Pacific Hurricane Center. Here’s a tracking map covering both the eastern and central Pacific Ocean. A satellite image, which shows the entire ocean area between Hawaii and the Mexican coast…can be found here.

Aloha Paragraphs

Nice weather on most leeward beaches

The strong and gusty trade winds will continue to blow across our islands, thanks to a strong surface high pressure system to the north-northwest. This high pressure cell, currently weighing in at 1032 millibars, is nearly stationary Tuesday afternoon. This weather map shows this feature, with a ridge extending eastward from the flank of this large high pressure system. The high will gradually shift more eastward later this week, although be re-enforced from the northwest, by another high over the weekend. Wind speeds have likely peaked out now for the current windy episode…over the last two days actually. The strongest gusts were ranging between 50-60 mph on the Big Island, with all the islands finding 30-40+ mph gusts during this time frame. Just because the peak has passed though, doesn’t mean that we don’t still have a steep pressure gradient over the state…although it has slipped some since yesterday.

The strongest wind gusts Tuesday afternoon were riding up above the 30 mph mark…with a few over 40…all the way up to 50 mph at Kawaihae on the Big Island. This is a different kind of trade wind pattern than we’ve seen for quite some time…in that it will last quite a while. The wind flow started off coming directly out of the north, bringing cooler air into play over our tropical islands. It then shifted a bit towards the east, taking on a more northeasterly orientation. Today it veered all the way around to the east-northeast, which can be thought of as a true trade wind direction. This new direction has taken the cool edge off these strong and gusty trade winds, with both warmer air temperatures during the day and nighttime hours. During the next several days the local wind speeds might come down another ½ a notch, perhaps tripping a full notch as we move into the weekend.

As for precipitation, there isn’t going to be all that much, as the air mass over Hawaii remains somewhat drier now. The looping satellite image in the paragraph above, shows that the rather copious stratocumulus and cumulus clouds that were around overnight into early this morning…have thinned under the influence of sunshine. The majority of whatever showers that do fall will occur along the windward sides during the cooler night and early morning hours. There’s no guarantee’s that the leeward sides, at least on the smaller islands, won’t see a few light sprinkles flying over from the windward sides…as long as the trade winds are as strong as they are now. The computer models want to increase our windward biased showers a bit towards Thursday and Friday…only to take them away again, as we move into the upcoming weekend. As the trade winds pick up again early next week, we might see a corresponding increase in showers again then for several days.

It’s Tuesday evening, as I begin writing this last section of today’s narrative.  As noted in the paragraphs above, our windy weather continues. As I pointed out this morning, here’s the top gusts at around 5pm on each of the islands – 35 mph on Kauai; 35 mph on Oahu; 38 mph on Molokai; 42 mph on Lanai; 46 mph on Kahoolawe; 37 mph on Maui; and 46 mph on the Big Island. These are not small numbers, and represent stronger than normal trade wind speeds, any way you look at it. The expectation is that this air flow will carry forward right into mid-week. As the air is coming in over a warmer ocean surface now, due to the east-northeast direction…our weather has warmed up nicely. This satellite image shows evidence of drier air coming our way. That being said, as the air mass cools during the night, there will likely be some increase in clouds along the windward coasts and slopes…with a modest increase in showers locally. Wednesday should be a decent day weatherwise, that is if you don’t mind the blustery winds. ~~~ I’m getting ready to head upcountry now, and look forward to being in Kula before sunset. I’ll be back at the drawing boards again early Wednesday morning, ready to prepare your next new weather narrative from paradise. I hope you have a great Tuesday night until then! Aloha for now…Glenn.

Interesting: The February 27 magnitude 8.8 earthquake in Chile may have shortened the length of each Earth day. JPL research scientist Richard Gross computed how Earth’s rotation should have changed as a result of the Feb. 27 quake. Using a complex model, he and fellow scientists came up with a preliminary calculation that the quake should have shortened the length of an Earth day by about 1.26 microseconds (a microsecond is one millionth of a second).

Perhaps more impressive is how much the quake shifted Earth’s axis. Gross calculates the quake should have moved Earth’s figure axis (the axis about which Earth’s mass is balanced) by 2.7 milliarcseconds (about 8 centimeters, or 3 inches). Earth’s figure axis is not the same as its north-south axis; they are offset by about 10 meters (about 33 feet).

By comparison, Gross said the same model estimated the 2004 magnitude 9.1 Sumatran earthquake should have shortened the length of day by 6.8 microseconds and shifted Earth’s axis by 2.32 milliarcseconds (about 7 centimeters, or 2.76 inches).

Gross said that even though the Chilean earthquake is much smaller than the Sumatran quake, it is predicted to have changed the position of the figure axis by a bit more for two reasons. First, unlike the 2004 Sumatran earthquake, which was located near the equator, the 2010 Chilean earthquake was located in Earth’s mid-latitudes, which makes it more effective in shifting Earth’s figure axis.

Second, the fault responsible for the 2010 Chilean earthquake dips into Earth at a slightly steeper angle than does the fault responsible for the 2004 Sumatran earthquake. This makes the Chile fault more effective in moving Earth’s mass vertically and hence more effective in shifting Earth’s figure axis. Gross said the Chile predictions will likely change as data on the quake are further refined.

Interesting2: In Switzerland, two pioneers are coming closer and closer to a flight around the world powered only by solar energy. It doesn’t make good business sense, physics sense, or much of any kind of sense, to try to fly an airplane on solar power.

Not yet. With the state of the technology, and how relatively young the solar sector still is, such an endeavor would be considered quixotic today—let alone in 2003, when Bertrand Piccard and André Borschberg, co-founders of Solar Impulse, announced they would design a solar-powered aircraft and fly it around the world.

It would be a statement, they said, about our global dependence on fossil fuels and the untapped promise of burgeoning green technologies. The Swiss pilot-entrepreneurs were after "perpetual flight": a plane that could climb to 9,000 feet and fly on the sun’s energy by day, then descend below cloud cover to lower altitudes, where it would cruise on stored battery power by night.

It was a long shot. And yet seven years of innovation later, the 70-person Solar Impulse team is nearing its goal. "We were intrigued by this notion of perpetual flight," said Borschberg when visited in September in Solar Impulse’s massive hangar, situated smack in the middle of Düendorf Airfield, a Swiss military zone.

"We wanted to be totally independent of any fuel." Forget hybrid planes, or the biofuels fixating most of the sustainable aviation sector today; Piccard and Borschberg are purists. "No fuel, no CO2, no pollution. It could fly almost forever, assuming good weather," Borschberg said of their invention.

By November of last year, test pilot Markus Scherdel—formerly of DLR German Aerospace, the NASA of Germany—was climbing into the cockpit of the completed prototype to taxi down the Dübendorf runway for the first time. Soon after that, Scherde was back in the cockpit, this time guiding the plane not just down the runway but up into the air for a series of successful "flea-hop" mini-flights over the tarmac.

The Solar Impulse HB-SIA, as it is officially named, is a strange sight to behold. Resting under the sky-high ceiling of its hangar at Dubendorf, it looks fragile to the point of breakable. And no wonder: HB-SIA, comprised of a carbon skeleton covered in a flexible polycarbonate “skin,” weighs only about 1.5 tons, about as much as a small car.

Its wings are so light that a single person can carry them. And when I tested both the pilot’s parachute and the detached nosepiece of a second prototype of the plane for weight, the parachute was heavier.

Interesting3: When one thinks of plague one thinks of the Black Plague in Europe in the Dark Ages that was spread by rodents. However, plague also affects wildlife where a reservoir of the disease is maintained. Plague, a flea borne bacterial disease introduced to North America in the late 1800s, spreads rapidly across a landscape, causing devastating effects to wildlife and posing risks to people.

Conservation and recovery efforts for imperiled species such as the black footed ferret and Utah prairie dog are greatly hampered by the effects of plague. Eruptions of the fatal disease have wiped out prairie dog colonies, as well as dependent ferret populations, in many locations over the years.

Plague has been identified as a disease of concern to human, wildlife and domestic animal populations within the United States. This infectious disease is caused by the bacterium Yersinia pestis and is primarily vectored by fleas. This same bacteria caused three human epidemics in recorded history; today, wildlife act as reservoirs for the bacteria throughout the world in arid areas.

Plague mostly affects, and is found within, rodent populations such as chipmunks, ground squirrels and prairie dogs, but can also affect other mammals, such as carnivores and scavengers that feed on rodents. Plague represents a health and safety threat to humans, especially in places where humans and rodents interface. There are currently about a dozen human plague cases reported each year.

In new research (special issue of Vector-Borne and Zoonotic Diseases), it is demonstrated that plague continues to affect the black footed ferret, one of the most critically endangered mammals in North America, as well as several species of prairie dogs, including the federally threatened Utah prairie dog even when the disease does not erupt into epidemic form.

“The impacts of plague on mammal populations remain unknown for all but a few species, but the impact on those species we have studied raises alarms as well as important questions about how plague might be affecting conservation efforts in general,” said Dean Biggins, a wildlife biologist with the U.S. Geological Survey and co-author of two papers in the special issue.

Biggins’ and his colleague’s research indicates that plague may be maintained in the wild within colonies of prairie dogs, the primary food of black footed ferrets, without causing the large scale, rapid die off of prairie dogs that is commonly observed. The mechanisms of the bacterium’s low level presence and survival, as well as the absence of a large scale die off of prairie dogs, remain under investigation.

“The overall difficulty of detecting plague in the absence of a large scale die off serves as a warning for those dedicated to wildlife conservation and human health,” Biggins said. “Hazards from plague may exist even where there have never been epidemics that caused widespread and readily detectable levels of mortality among local rodents such as prairie dogs.” Two years ago, for example, a National Park Service employee in Arizona died of plague contracted from an infected cougar that he had found dead, even though a plague epidemic had not been observed in resident prairie dog populations.

Interesting4:   Besides aftershocks, Chile’s magnitude 8.8 earthquake on 27 February may also leave a legacy of volcanic explosions. "We expect to see an upsurge in volcanic activity over the next 12 months," says David Pyle, a volcanologist at the University of Oxford. Charles Darwin was among the first people to suggest a link between large earthquakes and increased volcanic activity.

In his records, he notes that a large earthquake off Chile’s coastline in February 1835 appeared to resurrect previously inactive volcanoes, and cause active ones to increase their eruption rates. Last year, Pyle and his colleagues confirmed that this was a real effect in Chile, showing that increases in volcanic activity have occurred following other large earthquakes along its coastline.

In particular, they found that after a magnitude 8.3 in 1906 and a magnitude 9.5 earthquake in 1960, there were three or four more volcanic eruptions within about 500 kilometers of the epicenter in the following year than would normally be expected. Last week’s earthquake occurred on the same section of fault that caused the earthquake Darwin observed in 1835.

"We’ll be using satellite measurements of heat and deformation to keep an eye on the entire arc of volcanoes, from Llaima in the south to Tupungatito in the north," says Pyle. Pyle stresses that the risk to local people from this extra volcanism is likely to be minimal. "At volcanoes that are already active we might see an increase in steam explosions, but we don’t expect it to present a significantly increased danger," he says.