Hawaiian Islands Weather details & Aloha paragraphs / November 15-16, 2011

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

Lihue, Kauai –                   79
Honolulu airport, Oahu –   87   (record high for the date – 90 in 1995)  
Kaneohe, Oahu –               82
Molokai airport –                85
Kahului airport, Maui          84
Kona airport                      83
Hilo airport, Hawaii –          82

Air Temperatures ranged between these warmest and coolest spots near sea level – and on the highest mountain tops…as of 5pm Tuesday evening:

Honolulu, Oahu – 83
Kapalua, Maui – 75

Haleakala Crater –     45 (near 10,000 feet on Maui)
Mauna Kea Summit – 32 (over 13,500 feet on the Big Island)

Here are the 24-hour precipitation totals (inches) for each of the islands as of Tuesday evening:

0.60     Mount Waialeale, Kauai
0.04     Punaluu Pump, Oahu
0.00     Molokai
0.00     Lanai
0.00     Kahoolawe
0.00     Maui
0.39     Saddle Quarry, Big Island

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 during the day and night. This next image is one that gives close images of the islands during the daytime hours, and is referred to as a Close-up visible image. 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 web cam on the summit of near 13,500 foot Mauna Kea on the Big Island of Hawaii. This web cam is available during the daylight hours here in the islands…and when there’s a big moon shining down during the night at times. Plus, during the nights you will be able to see stars, and the sunrise and sunset too…depending upon weather conditions. The Haleakala Crater webcam on Maui just came back online, after being on the blink for several weeks.

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. A satellite image, which shows the entire ocean area between Hawaii and the Mexican coast…can be found here.  Here's a tropical cyclone tracking map for the eastern and central Pacific.

 Aloha Paragraphs

Increasing high and middle level clouds 

As this weather map shows, we find a 1032 millibar high pressure system located about two thirds of the way towards the west coast…to the northeast of the Hawaiian Islands this evening. This high pressure cell has an elongated ridge extending from its western flank, which continues into the area northwest of Kauai. At the same time, there are two low pressure systems located to the north and northwest of Hawaii. There are cold fronts that are associated with these low pressure centers, which are helping to limit the strength of our local trade winds…at least for the moment. Our trade winds will build in strength after mid-week, remaining on the strong and gusty side into early next week.

The following numbers represent the strongest wind gusts (mph), along with directions Tuesday evening:

10                 Port Allen, Kauai – SE
17                 Kahuku, Oahu – ENE
07                 Molokai – NE
24                    Kahoolawe – ESE
22                 Lipoa, Maui – ESE
05                 Lanai – SE
24                    Upolu Point, Big Island – NE

We can use the following links to see what’s going on in our area of the north central Pacific Ocean early Tuesday evening. Looking at this NOAA satellite picture we find a minimal amount of low cloudiness over and around the islands, with a maximum amount heading our way at the upper levels of the atmosphere. We can use this looping satellite image to see thunderstorm cells firing off far to our southwest, south, southeast, and northeast. Meanwhile, there are considerable high and middle level clouds riding in over us from the west! Checking out this looping radar image we see very few showers over the ocean, the majority of which are located to the southeast of the Big Island again tonight.

Sunset Commentary:  Our mid November weather has remained very nice for this time of year, with lots of generally clear skies, and limited rainfall. This fairly routine weather pattern held firm through the day, although that is about to change, becoming way cloudier as we move into Wednesday and beyond. These clouds are associated with an upper level low pressure trough, which will drop off a low pressure system to the west of Kauai Wednesday into Thursday. This low will bring colder air temperatures aloft then, which will destabilize the atmosphere over the state, especially near Kauai for a few days. This in turn will prompt some enhancement to our local showers…depending upon how close it gets.

Meanwhile, our trade winds are fairly light at the moment, although there are some stronger gusts in those typically windier locales. These light to moderately strong trade winds will remain with us through Wednesday, although will accelerate Thursday, and remain stronger and gusty through the weekend into early next week. As these stronger trade winds arrive, thanks to a strengthening high pressure system to the north-northeast, they will help to carry moisture our way. The main benefit from these passing showers will grace the windward sides, and around the Kauai end of the state potentially too. If the winds gain enough speed, some of this precipitation will be carried over into the leeward sides of the islands as well. As the air will be cold aloft later this week, there may be some light snow falling atop the tall mountains on the Big Island then too. [This Big Island webcam is available for viewing during the daylight hours.]

Here in Kihei, Maui at around 530pm Tuesday evening, there were clear to partly cloudy skies, although it was quite cloudy upcountry towards the Haleakala Crater too. As I was writing above, we've got a ton of high and middle level clouds to our west, which will give us partly to mostly cloudy skies through much of the rest of this week. This looping satellite image shows these clouds looming to the west of us…and now spreading over us. This moisture will stick around for several days, and likely mute our Hawaiian sunshine during the days. The good thing about these cirrus clouds however, is that they provide beautiful sunrise and sunset colors!  I'll be back again early Wednesday morning with more information about all of the above, I hope you have a great Tuesday night until then! Aloha for now…Glenn.

Interesting: Adaptation is fundamental for a species to survive, especially in hostile environments like the Arctic. When faced with six months of perpetual darkness where snow and ice lays claim to every inch of the land. What kind of extraordinary animals survive in such harsh terrain, and more importantly, how do they do it?

During winter in the Arctic, temperatures can drop to a bone-chilling −58 °F. Rather than going into hibernation however, some animals will stick out the winter and use their cold-conquering adaptations to survive. One such animal that has done this is the arctic fox or the snow fox as it is also commonly known.

Ranging far and wide in the arctic and alpine tundra, these jackals of the north, so-called because of their propensity to scavenge on polar bears' kills, have a woolly coat that has the best insulating properties of any mammal. Other adaptations for life in the arctic include small, heavily furred ears and a short nose.

Having a smaller surface area reduces heat loss. They also have fur on the soles of their feet as well as increased blood circulation to the feet which literally stops their paws freezing to the ice! Another such master of retaining body heat is the walrus.

Walrus are covered with short coarse hair that becomes less dense as they get older. Their skin which is folded and wrinkled can be up to 2 inches thick serving as a great insulator. This tough skin is the thickest on the neck and shoulders of adult males where it also serves as a defensive purpose — when these bulls spar the thick skin is intended to resist tusk penetration.

They have a deposit of fatty tissue that is up to an astounding 6 inches thick – in winter it may make up to a third of their body mass. As well as being an excellent insulator it also streamlines the body and is used as an energy reserve.

Their outer defenses serve as a pretty hardy armoury but even this thickest of "winter coats" is not sufficient when diving to depths of over 180 meters for nearly half an hour at a time, so the walrus has another trick up its sleeve.

When they enter the cold arctic water they become paler because they have a mechanism that restricts blood flow to the skin in order to reduce heat loss. Conversely, when walruses are warm their skin is flushed with blood and they appear to be very red.

The adaptations that allow animals to live in such a hostile environment are incredible; join us again when we check out some even more incredible adaptations — those of the animals who inhabit the coldest place on earth, the Antarctic.

Interesting2: The first climate study to focus on variations in daily weather conditions has found that day-to-day weather has grown increasingly erratic and extreme, with significant fluctuations in sunshine and rainfall affecting more than a third of the planet. Princeton University researchers recently reported in the Journal of Climate that extremely sunny or cloudy days are more common than in the early 1980s, and that swings from thunderstorms to dry days rose considerably since the late 1990s. These swings could have consequences for ecosystem stability and the control of pests and diseases, as well as for industries such as agriculture and solar-energy production, all of which are vulnerable to inconsistent and extreme weather, the researchers noted.

The day-to-day variations also could affect what scientists can expect to see as Earth's climate changes, according to the researchers and other scientists familiar with the work. Constant fluctuations in severe conditions could alter how the atmosphere distributes heat and rainfall, as well as inhibit the ability of plants to remove carbon dioxide from the atmosphere, possibly leading to higher levels of the greenhouse gas than currently accounted for.

Existing climate-change models have historically been evaluated against the average weather per month, an approach that hides variability, explained lead author David Medvigy, an assistant professor in the Department of Geosciences at Princeton. To conduct their analysis, he and co-author Claudie Beaulieu, a postdoctoral research fellow in Princeton's Program in Atmospheric and Oceanic Sciences, used a recently developed computer program that has allowed climatologists to examine weather data on a daily level for the first time, Medvigy said.

"Monthly averages reflect a misty world that is a little rainy and cloudy every day. That is very different from the weather of our actual world, where some days are very sunny and dry," Medvigy said.

"Our work adds to what we know about climate change in the real world and places the whole problem of climate change in a new light," he said. "Nobody has looked for these daily changes on a global scale. We usually think of climate change as an increase in mean global temperature and potentially more extreme conditions — there's practically no discussion of day-to-day variability."

The Princeton findings stress that analysis of erratic daily conditions such as frequent thunderstorms may in fact be crucial to truly understanding the factors shaping the climate and affecting the atmosphere, said William Rossow, a professor of earth system science and environmental engineering at the City College of New York.

"It's important to know what the daily extremes might do because we might care about that sooner," said Rossow, who also has studied weather variability. He had no role in the Princeton research but is familiar with it.

Rossow said existing climate-change models show light rain more frequently than they should and don't show extreme precipitation. "If it rains a little bit every day, the atmosphere may respond differently than if there's a really big rainstorm once every week. One of the things you find about rainstorms is that the really extreme ones are at a scale the atmosphere responds to," he said.

Although climate-change models predict future changes in weather as the planet warms, those calculations are hindered by a lack of representation of day-to-day patterns, Rossow said.

"If you don't know what role variability is playing now, you're not in a very strong position for making remarks about how it might change in the future," he said. "We're at a stage where we had better take a look at what this research is pointing out."

Medvigy and Beaulieu determined sunshine variation by analyzing fluctuations in solar radiation captured by the International Satellite Cloud Climatology Project from 1984 to 2007. To gauge precipitation, the researchers used daily rainfall data from the Global Precipitation Climatology Project spanning 1997 to 2007.

Medvigy and Beaulieu found that during those respective periods, extremes in sunshine and rainfall became more common on a day-to-day basis. In hypothetical terms, Medvigy said, these findings would mean that a region that experienced the greatest increase in sunshine variability might have had partly cloudy conditions every day in 1984, but by 2007 the days would have been either sunny or heavily cloudy with no in-between. For rainfall, the uptick in variation he and Beaulieu observed could be thought of as an area experiencing a light mist every day in 1997, but within ten years the days came to increasingly fluctuate between dryness and downpour.

The researchers observed at least some increase in variability for 35 percent of the world during the time periods analyzed. Regions such as equatorial Africa and Asia experienced the greatest increase in the frequency of extreme conditions, with erratic shifts in weather occurring throughout the year. In more temperate regions such as the United States, day-to-day variability increased to a lesser degree and typically only seasonally. In the northeastern United States, for instance, sudden jumps from sunny to bleak days became more common during the winter from 1984 to 2007.

In the 23 years that sunshine variability rose for tropical Africa and Asia, those areas also showed a greater occurrence of towering thunderstorm clouds known as convective clouds, Medvigy said. Tropical areas that experienced more and more unbalanced levels of sunshine and rainfall witnessed an in-kind jump in convective cloud cover. Although the relationship between these clouds and weather variations needs more study, Medvigy said, the findings could indicate that the sunnier days accelerate the rate at which water evaporates then condenses in the atmosphere to form rain, thus producing heavy rain more often.

Storms have lasting effect on daily weather patterns

Although the most extreme weather variations in the study were observed in the tropics, spurts of extreme weather are global in reach, Rossow said. The atmosphere, he said, is a fluid, and when severe weather such as a convective-cloud thunderstorm "punches" it, the disturbance spreads around the world. Weather that increasingly leaps from one extreme condition to another in short periods of time, as the Princeton research suggests, affects the equilibrium of heat and rain worldwide, he said.

"Storms are violent and significant events — while they are individually localized, their disturbance radiates," Rossow said.

"Wherever it's raining heavily, especially, or variably is where the atmosphere is being punched. As soon as it is punched somewhere in the tropics it starts waves that go all the way around the planet," he said. "So we can see waves coming off the west Pacific convection activity and going all the way around the planet in the tropical band. The atmosphere also has the job of moving heat from the equator to the poles, and storms are the source of heat to the atmosphere, so if a storm's location or its timing or its seasonality is altered, that's going to change how the circulation responds."

These sweeping atmospheric changes can interact with local conditions such as temperature and topography to skew regular weather patterns, Rossow said.

"Signals end up going over the whole globe, and whether they're important in a particular place or not depends on what else is happening," he said. "But you can think of storms as being the disturbances in an otherwise smooth flow. That's why this is a climate issue even though we're talking about daily variability in specific locations."

The impact of these fluctuations on natural and humanmade systems could be as substantial as the fallout predicted from rises in Earth's average temperature, Medvigy said. Inconsistent sunshine could impair the effectiveness of solar-energy production and — with fluctuating rainfall also included — harm agriculture, he said. Wetter, hotter conditions also breed disease and parasites such as mosquitoes, particularly in tropical areas, he said.

On a larger scale, wild shifts in day-to-day conditions would diminish the ability of trees and plants to remove carbon from the atmosphere, Medvigy said. In 2010, he and Harvard University researchers reported in the journal the Proceedings of the National Academy of Sciences that erratic rain and sunlight impair photosynthesis. That study concluded that this effect upsets the structure of ecosystems, as certain plants and trees — particularly broad-leafed trees more than conifers — adapt better than others.

In the context of the current study, Medvigy said, the impact of variability on photosynthesis could mean that more carbon will remain in the atmosphere than climate models currently anticipate, considering that the models factor in normal plant-based carbon absorption. Moreover, if the meteorological tumult he and Beaulieu observed is caused by greenhouse gases, these fluctuations could become self-perpetuating by increasingly trapping the gases that agitated weather patterns in the first place.

"We have not yet looked for direct ties between weather variability and increased carbon dioxide concentration in the atmosphere, but I would not be surprised if they are connected in some way," Medvigy said.

"Increases in variability diminish the efficiency with which plants and trees remove carbon dioxide from the air," he said. "All of a sudden, the land and the atmosphere are no longer in balance, and plants cannot absorb levels of carbon dioxide proportional to the concentrations in the environment. That will affect everybody."