Hawaiian Islands Weather details & Aloha paragraphs / November 29-30, 2012

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

Lihue, Kauai –                       79  
Honolulu airport, Oahu –        79  
Molokai airport –                    81
Kahului airport, Maui –       82 
Kona airport     –                   81  
Hilo airport, Hawaii –              80

Air Temperatures ranged between these warmest and coolest spots near sea level – and on the highest mountain tops around the state…as of 510pm Thursday evening:   

Barking Sands, Kauai – 78
Hilo, Hawaii  –  74

Haleakala Summit –   M       (near 10,000 feet on Maui)
Mauna Kea Summit – 36        (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.

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.

Aloha Paragraphs

Unsettled weather, showers, some locally heavy,
will take over later this weekend into early next week…
first on the Kauai and Oahu side of the island chain

The following numbers represent the most recent top wind gusts (mph), along with directions as of Thursday evening:

09            Mana, Kauai – SE
14            Makua Range, Oahu – SW 
08            Molokai – NE    
16            Kahoolawe – ESE
10            Kula 1, Maui – NW
12            Lanai – SSW
20            PTA West, Big Island – N

Here are the latest 24-hour precipitation totals (inches) for each of the islands as of Thursday evening:
 
0.08          Poipu, Kauai
0.16          Hakipuu Mauka, Oahu
0.00          Molokai
0.00          Lanai
0.00          Kahoolawe
0.11          Hana airport, Maui
0.02          Kawainui Stream, Big Island  

We can use the following links to see what’s going on in our area of the north central Pacific Ocean.  Here's the latest NOAA satellite picture – the latest looping satellite image…and finally the latest looping radar image for the Hawaiian Islands.

                                          ~~ Hawaii evening commentary ~~ 

Generally light breezes will come up from the southwest and southeast, which will bring volcanic haze over some parts of the Aloha state.  We currently have a weak near 1017 millibar high pressure system (weather map), located over the ocean northeast of Hawaii…moving away slowly towards the east. Meanwhile, we find multiple low pressure systems to our northwest and northeast. Our local winds will come up from the south and southeast into Friday, with onshore sea breezes during the day. As we get into the weekend, we'll find our winds blowing from the southwest to southeast, as a cold front moves in our direction from the west and northwest. 

As we look at this satellite image, we see an area of considerable high cirrus clouds streaming over us from the west and southwest. As these high clouds move overhead, we'll see filtering and dimming of our sunshine during the days, and of the moonlight overnight. Friday will start off in partly cloudy way, with those wispy cirrus very likely still over us. As we push into the afternoon, we'll see more of those upcountry clouds forming, although with just a few showers here and there. This relatively dry convective weather pattern will continue into Saturday.

As we get into the weekend, we're in store for changes, with rainfall, some locally heavy…especially on the Kauai and Oahu end of the island chain by Sunday. The weather will take on a wetter character, as low pressure forms over the ocean to our west and northwest. The Kauai end of the island chain will be effected by these changes first, as soon as later Saturday. The eastern islands may get into this showery weather picture too, although it may take awhile longer. It appears that this will be a fairly extended period with off and on showers, as southerly winds carry moisture up over us from the deeper tropics. There's a good chance that some of these showers will eventually be on the heavy side, with localized flooding not out of the question. In sum: pretty good weather Friday and Saturday, then by Saturday night or Sunday, Kauai and likely Oahu will see increasing clouds and precipitation. I'll have more updates on all of the above early Friday morning, when I'll be back with your next new weather narrative. I hope you have a great Thursday night until then! Aloha for now…Glenn.

World-wide tropical cyclone activity:

Atlantic Ocean/Caribbean Sea:  There are no active tropical cyclones

Gulf of Mexico: There are no active tropical cyclones

Eastern Pacific Ocean: There are no active tropical cyclones

Central Pacific Ocean:  There are no active tropical cyclones

Western Pacific Ocean:  Tropical cyclone Bopha (26W) remains active in the western Pacific…located approximately 605 NM east-southeast of Palau. Sustained winds were 65 knots, with gusts to near 80 knots. The JTWC indicates that this typhoon will move well southwest of Guam, south of Yap, then right over Palau…and onwards into the central Philippine Islands. Here's the JTWC graphical track map…along with a satellite image.

South Pacific Ocean:   There are no active tropical cyclones

North and South Indian Oceans:  There are no active tropical cyclones

Interesting:  Due to its location at the South Pole, Antarctica receives relatively little solar radiation. This means that it is a very cold continent where water is mostly in the form of ice or snow. This accumulates and forms a giant ice sheet which covers the land. New data which more accurately measures the rate of ice-melt could help us better understand how Antarctica is changing in the light of global warming.

The rate of global sea level change is reasonably well-established but understanding the different sources of this rise is more challenging. Using re-calibrated scales that are able to weigh ice sheets from space to a greater degree of accuracy than ever before, the international team led by Newcastle University has discovered that Antarctica overall is contributing much less to the substantial sea-level rise than originally thought.

Instead, the large amount of water flowing away from West Antarctica through ice-melt has been partly cancelled out by the volume of water falling onto the continent in the form of snow, suggesting some past studies have overestimated Antarctica’s contribution to fast-rising sea levels. Using Gravity Recovery and Climate Experiment (GRACE) satellite data, the team calculated ice sheet mass loss by more accurately mapping and removing the mass changes caused by the flow of rock beneath Earth’s surface.

Publishing their findings in the academic journal Nature, project lead Professor Matt King said the data meant we were at last close to understanding how Antarctica is changing. "We have tried to weigh the ice in the past but GRACE only measures the combined effect of the ice changes and the land mass changes occurring beneath the Earth’s surface," explains Professor King, Professor of Polar Geodesy at Newcastle University.

"The step forward we have made is to provide a better calculation of the land mass changes so we can correct the satellite measurements to more accurately calculate the changes in ice mass alone." "Our ice change calculations rely heavily on how well we can account for these important changes taking place beneath the Earth’s surface.

While the land beneath the ice is moving by no more than a few millimeters-per-year — the thickness of a fingernail — that seemingly small effect significantly alters the rate at which we estimate the ice is changing." "By producing a new estimate of the land motion we’re effectively re-calibrating the scales — in this case the GRACE satellite —so we can more accurately weigh the ice.

And what we’ve found is that present sea level rise is happening with apparently very little contribution from Antarctica as a whole." "We’re now confident it is shrinking," says Professor King. "Our new estimate of land motion helps us narrow the range and shifts the best estimate to the lower end of the ice melt spectrum." "Worryingly, though, the rate of shrinking has sped up in some important locations.

The parts of Antarctica that are losing mass most rapidly are seeing accelerated mass loss and this acceleration could continue well into the future." "The sea level change we’re seeing today is happening faster than it has for centuries with just a small contribution from the massive Antarctic ice sheet. What is sobering is that sea levels will rise even faster if Antarctica continues to lose increasingly more ice into the oceans."

Sea levels around the world are rising. Between 1870 and 2004, global average sea levels rose 17 cm as reported in 2006 in Geophysical Research Letters. From 1950 to 2009, satellite data showed a rise of 3.3 ± 0.4 mm from 1993 to 2009. In 2007, the Intergovernmental Panel on Climate Change (IPCC) projected that during the 21st century, sea level will rise another 7.1 to 23 inches.

Ice sitting on the Antarctic continent at the peak of the last ice age 20,000 years ago forced the rock beneath to deform and slowly flow away. After that time ice levels generally reduced and the rock within the Earth's mantle more than 100km below the surface has been slowly flowing back in. That change affects the GRACE satellites in exactly the same way as ice moving into and out of the continent and it has to be factored in to get an accurate measurement of the total ice.