Storms over the Pacific

SUBHEAD: Solar storms and global warming can be a nasty brew for small islands in the Pacific.

By Juan Wilson on 8 June 2013 for Island Breath -
(http://islandbreath.blogspot.com/2013/06/storms-over-pacific.html)


Image above: Diagram illustration of the Sun and Coronal Mass Ejection affecting Earth. From (http://www.universetoday.com/96286/incoming-cme-on-its-way-toward-earth/).

Have you noticed how bright the sun has been here om Kauai in the last couple of weeks? Sure, we're heading into the Summer Solstice when the sun is directly overhead at noon and the days are the longest. But what I'm talking about is in addition to that factor.

Coronal Mass Ejection
The sun at noon has seemed less yellow and almost white hot. In penetrates your eyes and seems to burrow through the skin... that's because it is doing just that.

We are in the midst of a strong solar magnetic storm that began in late May 2013 and that has loosed  a large Coronal Mass Ejection (CME) aimed toward the Earth. A CME is a ejected cloud of charged radioactive particles. This is a real health threat to people at high altitude or in high flying planes for long periods.

See article below.

These solar phenomena are not related to global warming or climate change, but they can have an exacerbating effect on global warming disruptions. The incoming radiation from a major CME can interfere or even knock out telecommunications. The withering sunlight and radiation can add to the stress of plants suffering from global warming induced drought and increased storms.

Trade Winds
Perhaps the most obvious symptom of the effects of Global Warming here in Hawaii has been the reduction in days that the Trade Winds blow from the North East. A generation ago the average was that Trade Winds blew close to 300 days a year. Now that number is closer to 200 days a year. That means less cooling moisture arriving in Hawaii and more vog blowing up from from volcanic action on the Big Island.

The results are Hawaii feels more hot and stuffy and the air can sometimes burn your throat.

See article below.

Ocean Temperature
Another effect of global warming in Hawaii is higher ocean temperatures. Since the mid 1970's that has meant worldwide average land and ocean surface temperatures have risen one degree Fahrenheit.

Temperature today in Nawiliwili 80.2º
Nawiliwili Harbor average surface ocean temperature from NOAA (http://www.nodc.noaa.gov/dsdt/cwtg/hawaii.html)

MAR   APR    MAY    JUN    JUL    AUG    SEP    OCT
 77ºF   78ºF    79ºF    81ºF   82ºF   82ºF   83ºF    82ºF

Ocean temperatures only vary few degrees Fahrenheit in a whole year. But even small variations can make a big difference in weather. Historically emperatures about 82ºF meant an increase the likelihood of the formations of Pacific hurricanes that can impact Hawaii.

Fortunately, as ocean temperatures have risen, so has the threshold temperatures that can kick off a destructive hurricane.

See article below.

Conclusion
It has been my hope that Hawaii, and specifically Kauai, would do better than average in terms of negative impacts due to more chaotic weather as Climate Change kicks in due to global warming.

I do believe that there is huge ocean flywheel effect that stabilizes temperatures to the magnitude of the Pacific Ocean (more than a quarter of Earth's surface). The shear mass of ocean and sky away from  most of the the industialization of mankind still gives me hope.

However, I can see how a combination of weather elements that could come together in a Perfect Storm and make Hawaii more like a Martian landscape.

NASA Warns of Solar Storms

By N. Arun Kumar on 24 May 2013 for Deccan Chronicle -
(http://www.deccanchronicle.com/130524/news-businesstech/article/nasa-warns-solar-storm)


Video above: NASA images of CME. From (http://youtu.be/xLvIXYmuhHM).

Nasa scientists have forecast a major ‘threat’ to Earth. A strong solar radiation storm has erupted from the Sun and it will affect passengers and crew in high altitude flights owing to increasing radiation exposure, they have warned.

Nasa has also cautioned that the emission of high-energy particles (protons) from the Sun may affect all satellite systems. Nasa’s space weather prediction centre located at Boulder in Colorado, USA, has come out with a bulletin according to which the solar radiation storm has reached S3 (strong) level at 3 am UTC (8.30 am IST) on May 23.

A solar storm or solar flare occurs when magnetic energy that had built up in the solar atm­o­sphere is sudd­enly released with high bursts of energy.

Radiation is emitted across the entire electromagnetic spe­cr­um from the radio waves at the long wavelength end, through optical emission to x-rays and gamma rays at the short wavelength end. The amo­unt of en­ergy released is equivalent of millions of 100-megaton hydrogen bombs exploding at the same time.

The bulletin also pointed out that the expanding cloud from coronal mass ejection appears to deliver a glancing blow to Earth’s magnetic field. According to National Oceanic and Atmospheric Administration (NOAA) forecast models, the impact will be more than double the solar wind plasma density around Earth and boost the solar wind speed to about 600 km per second, which will be a treat to sky watchers as they can look at Sun’s aurora.

Spaceweather.com, one of the reputed websites for spaceweather, says S3 class solar storm will put passengers in commercial jets at high latitudes at risk as they may receive low-level radiation exposure (approximately one chest x-ray), satellite operations will be affected with noise in imaging systems, and slight reduction of efficiency in solar panel. The storm can also degrade high frequency (HF) radio propagation through polar regions and navigation position errors can also be expected.



Decrease in Trade Winds

(http://www.sciencedaily.com/releases/2012/10/121012102615.htm)

Scientists at University of Hawaii at Manoa (UHM) have observed a decrease in the frequency of northeast trade winds and an increase in eastern trade winds over the past nearly four decades, according to a recent study published in the Journal of Geophysical Research. For example, northeast trade wind days, which occurred 291 days per year 37 years ago at the Honolulu International Airport, now only occur 210 days per year.



Jessica Garza, a Meteorology Graduate Assistant at the School of Ocean and Earth Science and Technology (SOEST) at UHM; Pao-Shin Chu, Meteorology Professor and Head of the Hawaii State Climate Office; Chase Norton; and Thomas Schroeder analyzed 37 years of wind speed and direction, and sea level pressure data from land-based weather stations, buoys and reanalysis data.

Persistent northeast trade winds are important to the Hawaiian Islands because they affect wave height, cloud formation, and precipitation over specific areas of the region. When trades fail to develop the air can become

Furthermore, Chu explained that the trades are the primary source of moisture for rain, and that a dramatic reduction could fundamentally change Hawai'i's overall climate.

"We have seen more frequent drought in the Hawaiian Islands over the last 30 years," he noted. "Precipitation associated with the moisture-laden northeasterly trades along the windward slopes of the islands contributes much of the overall rainfall in Hawaii."


According to the National Drought Mitigation Center's State Drought Monitor, nearly 50% of land in Hawaii has experienced some degree of drought during the past year.


While previous research has focused primarily on changes in trade wind intensities, this work, along with Chu's 2010 study, is among the first to show changes in trade wind frequencies.


"In 2010, we only studied the trade wind changes at four major airports in Hawaii (Honolulu, Kahului, Hilo, and Lihue). In the current paper, we expanded our study to include four ocean buoys in the vicinity of Hawaii and a large portion of the North Pacific," Chu commented.


In the future, these scientists will be using model simulated data to further understand the dynamics of rainfall and trade winds, and estimate future patterns.



Temp threshold for hurricanes is rising

By Nat Johnson on 8 November 2008 for University of Hawaii - 

Scientists have long known that atmospheric convection in the form of hurricanes and tropical ocean thunderstorms tends to occur when sea surface temperature rises above a threshold. So how do rising ocean temperatures with global warming affect this threshold? If the threshold does not rise, it could mean more frequent hurricanes. A new study by researchers at the International Pacific Research Center (IPRC) of the University of Hawaiʻi at Mānoa shows this threshold sea surface temperature for convection is rising under global warming at the same rate as that of the tropical oceans. Their paper appears in the Advance Online Publications of Nature Geoscience.

In order to detect the annual changes in the threshold sea surface temperature (SST) for convection, Nat Johnson, a postdoctoral fellow at IPRC, and Shang-Ping Xie, a professor of meteorology at IPRC and UH Mānoa, analyzed satellite estimates of tropical ocean rainfall spanning 30 years. They find that changes in the threshold temperature for convection closely follow the changes in average tropical sea surface temperature, which have both been rising approximately 0.1°C per decade.

“The correspondence between the two time series is rather remarkable,” says lead author Johnson. “The convective threshold and average sea surface temperatures are so closely linked because of their relation with temperatures in the atmosphere extending several miles above the surface.”

The change in tropical upper atmospheric temperatures has been a controversial topic in recent years because of discrepancies between reported temperature trends from instruments and the expected trends under global warming according to global climate models. The measurements from instruments have shown less warming than expected in the upper atmosphere. The findings of Johnson and Xie, however, provide strong support that the tropical atmosphere is warming at a rate that is consistent with climate model simulations.

“This study is an exciting example of how applying our knowledge of physical processes in the tropical atmosphere can give us important information when direct measurements may have failed us,” Johnson notes.

The study notes further that global climate models project that the sea surface temperature threshold for convection will continue to rise in tandem with the tropical average sea surface temperature. If true, hurricanes and other forms of tropical convection will require warmer ocean surfaces for initiation over the next century. 
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