Hawaiian Islands Weather details & Aloha paragraphs / December 29-30, 2011

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

Lihue, Kauai –                   78
Honolulu airport, Oahu –    82  
Kaneohe, Oahu –               77
Molokai airport –                77
Kahului airport, Maui –        80  
Kona airport –                    79
Hilo airport, Hawaii –          78

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

Barking Sands, Kauai – 79
Hilo, Hawaii – 73

Haleakala Crater –  45 (near 10,000 feet on Maui)
Mauna Kea –         37 (near 13,800 feet on the Big Island)

Hawaii’s Mountains – Here’s a link to the live web cam on the summit of near 13,800 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. Here's the Haleakala Crater webcam on Maui…which is working only sometimes lately.

 Aloha Paragraphs

Gusty trade winds, just a few passing windward showers
 

As this weather map shows…we have a near 1030 millibar high pressure system to the east-northeast of the Hawaiian Islands Thursday evening.  This high pressure cell is well offshore from southern California, with a long ridge of high pressure extending west-southwest from its center. This ridge runs by the Hawaiian Islands, up around 27 degrees north latitude, and then further west to near the International Dateline. The location of this high pressure ridge is keeping our very long lasting strong and gusty trade winds blowing across Hawaii. There's forecast to be a gradual reduction in our wind speeds as we move through the rest of this last week of the year, becoming generally lighter into the first few days of 2012.

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

25                 Port Allen, Kauai – NE
31                 Honolulu, Oahu – NE
35                 Molokai – NE
46                    Kahoolawe – ENE
36                 Kahului, Maui – NE
33                 Lanai – NE
36                 South 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 Thursday evening.  Looking at this NOAA satellite picture we see patches of low level clouds upwind of the islands, which are generally dissipating as they move over the islands. The leeward sides remain generally clear at the time of this writing. We can use this looping satellite image to see towering cumulus and thunderstorms developing over the ocean far to the southwest and east-southeast of the islands. High cirrus clouds are evident to our north…moving along from generally west to east. At the same time, we see minor plumes of lower level clouds extending off the leeward sides of all the islands…at the time of this writing at least. Checking out this looping radar image we see just a few showers over the ocean, all of which are light…coming into our windward sides at times.

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

0.37               Mount Waialeale, Kauai
0.10               Hakipuu Mauka, Oahu
0.04               Molokai
0.00               Lanai
0.00               Kahoolawe
0.56               Puu Kukui, Maui
0.71                 Hilo airport, Big Island

Sunset Commentary:  The trade winds, which have been blustery most of this month, aren’t calming down just yet, although are expected to begin that process soon. We found winds gusting up between 40-45 mph in several places across Maui County and the Big Island Thursday afternoon. A long lasting high pressure system to our east-northeast, is spinning out these gusty trades across the tropical latitudes of the north central Pacific. There will be some changes taking place far to our north soon, up near the Gulf of Alaska. A couple of winter storms will be rolling by up there…which will in the process help to calm our local winds down quite a bit here locally, especially by later this weekend into early next week. The latest computer forecast models are suggesting that we could see the trade winds pick up their pace again after the middle of next week, in the wake of a possible cold front then.

As far as rainfall goes, there won’t be much of that, even on the windward sides…for a change. The overlying atmosphere remained dry and stable again today, so that last weeks wet weather has dried up significantly. This leaves the leeward sides without any showers, with just a few random light showers elsewhere. This dry reality will remain in place through the rest of the year, into the first couple of days of 2012 as well. As the winds lighten up this weekend, we’re apt to see daytime sea breezes. This in turn will prompt some afternoon clouds around the mountains…after clear and somewhat cooler than normal early mornings. The cold front for the middle of next week shouldn’t make too much of a splash, with the chance of increasing showers riding in on the returning trade winds in the wake of the front.

Here in Kihei, Maui at around 530pm HST, it was mostly clear in all directions. Today was a fine day, with lots of warm sunshine beaming down in most areas. Showers were at a bare minimum, with the leeward sides remaining dry as a bone. The trade winds will had this one last day to remain uppity, before we begin to notice more of a downward trend in their strength tomorrow into the weekend.  There is a pretty good chance that the trade winds might hold on enough, so that the fireworks smoke will be ventilated away adequately. ~~~ I'm heading back upcountry now, and as I leave Kihei I can see that the Haleakala Crater is almost cloud free, which makes for a great view. I'll be back early Friday morning with your next new weather narrative, I hope you have a great Thursday night until then! Aloha for now…Glenn.

Interesting:  Anything that goes into the ocean will eventually either sink or float. Debris from the tsunami that devastated Japan in March could reach the United States as early as this winter, according to predictions by NOAA scientists. However, they warn there is still a large amount of uncertainty over exactly what is still floating, where it's located, where it will go, and when it will arrive.

Responders now have a challenging, if not impossible situation on their hands: How do you deal with debris that could now impact U.S. shores, but is difficult to find? Just another garbage wave to worry about but one that is not directly a result of man's bad habits.

A tsunami is a huge volume of moving seawater. These giant waves can travel for thousands of miles across the sea and still have enough energy and force to destroy buildings, trees, wildlife and people. If you throw a stone in a pond it will create a series of ripples.

A tsunami is just like those ripples but the disturbance that sets them moving is much greater than a small stone. It can be triggered by an undersea earthquake, landslide or volcanic eruption. In March 2011 an underwater earthquake triggered a tsunami which hit Japan’s north-east coast.

The earthquake was the most powerful ever recorded in Japan causing a 30 foot tsunami wave to hit the city of Sendai and further devastate several coastal communities. This created tons and tons of shattered city stuff. As the tsunami surge receded, it washed much of what was in the coastal inundation zone into the ocean.

Boats, pieces of smashed buildings, appliances, and plastic, metal, and rubber objects of all shapes and sizes washed into the water — either sinking near the shore or floating out to sea. The refuse formed initially large debris fields captured by satellite imagery and aerial photos of the coastal waters.

Nine months later, debris fields are no longer clearly visible. Winds and ocean currents scattered items in the massive North Pacific Ocean to the point where debris is no longer visible from satellite. Vessels regularly traveling the North Pacific have reported very few sightings.

Only two sightings have been clearly linked to the tsunami. Computer models run by NOAA and University of Hawaii researchers show some debris could pass near or wash ashore in the Northwestern Hawaiian Islands (in the Papahnaumokukea Marine National Monument) as early as this winter, approach the West Coast of the United States and Canada in 2013, and circle back to the main Hawaiian Islands in 2014 through 2016.

The worst-case scenario is boats and unmanageable concentrations of other heavy objects could wash ashore in sensitive areas, damage coral reefs, or interfere with navigation in Hawaii and along the U.S. West Coast. Best case? The debris will break up, disperse and eventually degrade and sink, sparing coastal areas but adding to deep sea sediment.

Debris will not go away completely, even in a best-case scenario. Marine debris is an ongoing problem for Hawaii and West Coast states whether or not there is a Tsunami. Garbage and other harmful items regularly wash up on these beaches, reefs and other coastal areas.

Interesting2: Access to freshwater resources has always been a critical need for human and all forms of life on Earth. With a world population estimated at just shy of 7 billion and growing, the UN Food and Agriculture Organization says agricultural production will need to increase 70% by 2050.

As agriculture takes up most of human water use, that’s going to put vastly greater demands and strains on our water resources at a time when climate change is changing temperature and precipitation levels and patterns in ways that cannot be predicted at local levels but are likely to make this even more difficult to achieve.

One thing that has been determined is that groundwater levels have dropped in many places around the world in the past nine years, including across key agricultural areas, such as southern Argentina, western Australia and the western US, according to a pair of studies of satellite gravity monitoring data conducted by researchers at the University of California Center for Hydrologic Modeling in Irvine, Science News reports.

The GRACE Project

Groundwater depletion is especially pronounced beneath parts of California, India, the Middle East and China. Besides showing that water is being pumped out of underground groundwater aquifers faster than it’s being replenished, the results raise concerns that farming in particular is the primary cause, according to the Science News report. The Gravity Recovery and Climate Experiment (GRACE), conducted jointly by NASA and the German Aerospace Center, has been taking monthly snapshots of global groundwater used in the two studies since 2002.

GRACE data is especially useful in accumulating data across countries where governments do not maintain extensive networks of groundwater monitoring wells. While the US maintains an extensive nationwide network of such wells, countries, such as China, do not.

Nicknamed Tom and Jerry, GRACE’s two satellites are pulled apart and pushed together by variations in the gravitational pull of the areas of the earth they pass over. While mountains and other large concentrations of mass have large, steady impacts on earth’s gravitational pull on the areas where they’re found, water moves over time and creates small fluctuations that the two satellites sense.

Isolating groundwater changes

To isolate the effects of groundwater in particular, researchers have to subtract the effects of snow pack, rivers, lakes and soil moisture, the Science Times article explains. Doing so, they can detect changes in groundwater levels greater than ~0.4 inches over an area about the size of Illinois.

Results of analyzing the data obtained in the two UC Center studies shows that China’s been underestimating groundwater use. GRACE’s measurements indicate that water levels have been dropping 6 or 7 centimeters per year beneath the country’s northeast plains.

Short-term variability in climate is also taking its toll on groundwater levels. having suffered recent droughts, aquifers in Patagonia and the southeastern US now store less groundwater than they did in 2002.

Farming is almost certainly the largest contributing factor, however. Booming agriculture in northern India, takes some 18 cubic kilometers of water out of the ground every year, more than enough to fill 7 million Olympic-size swimming pools, according to Science News.

Farmers in California’s Central Valley, which accounts for nearly 1/6 of irrigated land in the entire country, pump nearly 4 cubic kilometers of water per year out from underground. The valley has been sinking for decades as more wells have been drilled and water pumped out, land subsidence that’s also been occurring and causing increasing concerns, and costly remediation efforts, in Mexico City.

Aquifers in arid and desert areas with fast-growing populations, such as the Middle East, are also being depleted. The “fossil water” that fell millions of years ago and is now stored in the Arabian aquifer beneath Saudi Arabia and neighboring countries is being pumped out faster than it’s being replenished.

Just how much water is there?

Climate change only makes the problem more acute, according to UC Center’s Famiglietti. Precipitation patterns are becoming more extreme, with the severity of droughts increasing. Wet areas are becoming wetters and dry areas drier, Science News reports, and that may accelerate groundwater depletion in some areas.

A big question remains unanswered, however, as hydrologists don’t really know just how large these aquifers are and just how much water is left in them. That’s because GRACE can only show changes in aquifer levels, not their total volume.

Yet while they lack reliable estimates for the total amount of groundwater stored in the world’s aquifers, it’s become clear to hydrologists studying them that water use has become unsustainable in many areas. Better irrigation systems would help reduce water usage, as could channeling water runoff into aquifers during wet periods.