Monday, November 12, 2012

desiderata


Max Ehrmann 


Desiderata 
Go placidly amid the noise and haste,
and remember what peace there may be in silence.
As far as possible without surrender
be on good terms with all persons.
Speak your truth quietly and clearly;
and listen to others,
even the dull and the ignorant;
they too have their story.
 

Avoid loud and aggressive persons,
they are vexations to the spirit.
If you compare yourself with others,
you may become vain and bitter;
for always there will be greater and lesser persons than yourself.
Enjoy your achievements as well as your plans.
 

Keep interested in your own career, however humble;
it is a real possession in the changing fortunes of time.
Exercise caution in your business affairs;
for the world is full of trickery.
But let this not blind you to what virtue there is;
many persons strive for high ideals;
and everywhere life is full of heroism.
 

Be yourself.
Especially, do not feign affection.
Neither be cynical about love;
for in the face of all aridity and disenchantment
it is as perennial as the grass.
 

Take kindly the counsel of the years,
gracefully surrendering the things of youth.
Nurture strength of spirit to shield you in sudden misfortune.
But do not distress yourself with dark imaginings.
Many fears are born of fatigue and loneliness.
Beyond a wholesome discipline,
be gentle with yourself.
 

You are a child of the universe,
no less than the trees and the stars;
you have a right to be here.
And whether or not it is clear to you,
no doubt the universe is unfolding as it should.
 

Therefore be at peace with God,
whatever you conceive Him to be,
and whatever your labors and aspirations,
in the noisy confusion of life keep peace with your soul.
 

With all its sham, drudgery, and broken dreams,
it is still a beautiful world.
Be cheerful.
Strive to be happy.
 

Monday, November 05, 2012

Fujiwara Effect




The Fujiwhara effect or Fujiwara interaction, named after Sakuhei Fujiwhara, is a type of interaction between two nearby cyclonic vortices, causing them to appear to "orbit" each other.

When the cyclones approach each other, their centers will begin orbiting cyclonically about a point between the two systems due to their cyclonic wind circulations. The two vortices will be attracted to each other, and eventually spiral into the center point and merge. When the two vortices are of unequal size, the larger vortex will tend to dominate the interaction, and the smaller vortex will orbit around it.
The effect is often mentioned in relation to the motion of tropical cyclones, although the final merging of the two storms is uncommon. The effect becomes pronounced in these storms when they approach within about 1,500 km (900 mi) of each other and are at tropical storm strength or stronger.

The effect is named after Sakuhei Fujiwhara, the Japanese meteorologist who initially described it in a 1921 paper about the motion of vortices in water



The Fujiwara Effect is an interesting phenomenon which can happen when two or more hurricanes form very near each other. In 1921, a Japanese meteorologist named Dr. Sakuhei Fujiwhara determined that two storms will sometimes move around a common center pivot point.
The National Weather Service defines the Fujiwhara Effect as the tendency of two nearby tropical cyclones to rotate cyclonically about each other. Another slightly more technical definition of the Fujiwhara Effect from the National Weather Service is a binary interaction where tropical cyclones within a certain distance (300-750 nautical miles depending on the sizes of the cyclones) of each other begin to rotate about a common midpoint. The effect is also known as the Fujiwara Effect without an ‘h’ in the name. USAToday provides an excellent graphic explaining theFujiwhara Effect.
Fujiwhara’s studies indicate storms will rotate around a common center of mass. A similar effect is seen in the rotation of the Earth and moon. This barycenter is the center pivot point around which two rotating bodies in space will spin. The specific location of this center of gravity is determined by the relative intensity of the tropical storms. This interaction will sometimes lead to tropical storms 'dancing' with each other around the dance floor of the ocean.

Tuesday, October 09, 2012

Tropical Cyclone


A tropical cyclone is a storm system characterized by a low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting incondensation of water vapor contained in the moist air. They are fueled by a different heat mechanism than other cyclonic windstorms such as nor'easters, European windstorms, and polar lows. The characteristic that separates tropical cyclones from other cyclonic systems is that at any height in the atmosphere, the center of a tropical cyclone will be warmer than its surroundings; a phenomenon called "warm core" storm systems.

The term "tropical" refers both to the geographical origin of these systems, which usually form in tropical regions of the globe, and to their formation in maritime tropical air masses. The term "cyclone" refers to such storms' cyclonic nature, with counterclockwise wind flow in the Northern Hemisphere and clockwise wind flow in the Southern Hemisphere. The opposite direction of the wind flow is a result of the Coriolis force. Depending on its location and strength, a tropical cyclone is referred to by names such as hurricane, typhoon, tropical storm, cyclonic storm, tropical depression, and simply cyclone.

While tropical cyclones can produce extremely powerful winds and torrential rain, they are also able to produce high waves, damaging storm surge, and tornadoes. They develop over large bodies of warm water, and lose their strength if they move over land due to increased surface friction and loss of the warm ocean as an energy source. This is why coastal regions can receive significant damage from a tropical cyclone, while inland regions are relatively safe from receiving strong winds. Heavy rains, however, can produce significant flooding inland, and storm surges can produce extensive coastal flooding up to 40 kilometres (25 mi) from the coastline. Although their effects on human populations can be devastating, tropical cyclones can relieve drought conditions. They also carry heat energy away from the tropics and transport it toward temperate latitudes, which makes them an important part of the global atmospheric circulation mechanism. As a result, tropical cyclones help to maintain equilibrium in the Earth's troposphere, and to maintain a relatively stable and warm temperature worldwide.

Many tropical cyclones develop when the atmospheric conditions around a weak disturbance in the atmosphere are favorable. The background environment is modulated by climatological cycles and patterns such as the Madden-Julian oscillation, El Niño-Southern Oscillation, and the Atlantic multidecadal oscillation. Others form when other types of cyclones acquire tropical characteristics. Tropical systems are then moved by steering winds in the troposphere; if the conditions remain favorable, the tropical disturbance intensifies, and can even develop an eye. On the other end of the spectrum, if the conditions around the system deteriorate or the tropical cyclone makes landfall, the system weakens and eventually dissipates. It is not possible to artificially induce the dissipation of these systems with current technology.




A tropical cyclone is composed of a system of thunderstorms that shows a cyclonic rotation around a central core or eye. A tropical cyclone is a generic term for a storm with an organized system of thunderstorms that are not based on a frontal system.
Each individual tropical cyclone differs, but several characteristics are common to most all tropical cyclones including a central low-pressure zone and high wind speeds of at least 34 knots. At this point, the storms are given a pre-determined storm name. Most storms are accompanied by a lot of rain and storm surges near the shore. Often, once the storms make landfall, the tropical cyclone can cause tornadoes.
A tropical cyclone needs warm ocean temperatures in order to form. Temperatures in the ocean need to be at least 82 degrees Fahrenheit in order to form. Heat is drawn up from the oceans creating what is popularly called a 'heat engine'. Tall convective towers of clouds are formed within the storm as warm ocean water evaporates. As the air rises higher it cools and condenses releasing latent heat which causes even more clouds to form and feed the storm.
Rotation and Forward Speed
The rotation of tropical cyclones in the Northern Hemisphere is counter-clockwise due to theCoriolis Effect. The opposite is true in the Southern Hemisphere.
The forward speed of a tropical cyclone can be a factor in determining the amount of damage the storm will cause. If a storm remains over one area for a long period of time, torrential rains, high winds, and flooding can severely impact an area. The average forward speed of a tropical cyclone is dependent on the latitude where the storm is currently. Generally, at less than 30 degrees of latitude, the storms will move at about 20 mph on average. The closer the storm is located the the equator, the slower the movement. Some storms will even stall out over an area for an extended period of time. After about 35 degrees North latitude, the storms start to pick up speed.
A good example of the fast formation of tropical cyclones comes when several storms stack up in the ocean back-to-back. Such an example occurred in 2009 with the formation of Ana, Bill, and Claudette as seen in this satellite image. The storms were very close to one another. Storms can also become entangle with one another in a process known as the Fujiwhara Effect where tropical cyclones can interact with each other.
Naming Tropical Cyclones
In the Atlantic Ocean and Eastern Pacific, tropical cyclones are known as hurricanes. In the Western Pacific Ocean, tropical cyclones are known as typhoons. In the Indian Ocean, a tropical cyclone is called a cyclone. These names are described in the article – Is it a typhoon, a cyclone, or a hurricane?
Specific storm names in each of the ocean basins vary based on conventional naming practices. For instance, in the Atlantic Ocean, storms are given names based on an alphabetical pre-determined list of Atlantic hurricane names. Severe hurricanes names are 


Tuesday, July 31, 2012


Tropical Depression
A tropical depression is designated when the first appearance of a lowered pressure and organized circulation in the center of the thunderstorm complex occurs. A surface pressure chart will reveal at least one closed isobar to reflect this lowering.

A Tropical depression is a tropical mass of thunderstorms with a cyclonic wind circulation between 20 and 34 knots.


LA NINA 
La Niña is a coupled ocean-atmosphere phenomenon that is the counterpart of El Niño as part of the broader El Niño-Southern Oscillation climate pattern. During a period of La Niña, the sea surface temperature across the equatorial Eastern Central Pacific Ocean will be lower than normal by 3–5 °C. In the United States, an episode of La Niña is defined as a period of at least 5 months of La Niña conditions. The name La Niña originates from Spanish, meaning "the girl," analogous to El Niño meaning "the boy."
La Niña, sometimes informally called "anti-El Niño", is the opposite of El Niño, where the latter corresponds instead to a higher sea surface temperature by a deviation of at least 0.5 °C, and its effects are often the reverse of those of El Niño. El Niño is famous due to its potentially catastrophic impact on the weather along both the Chilean, Peruvian, New Zealand, and Australian coasts, among others. It has extensive effects on the weather in North America, even affecting the Atlantic Hurricane Season. La Niña is often, though not always, preceded by an El Niño.


Effects?

The results of La Niña are mostly the opposite of those of El Niño; for example, El Niño would cause a dry period in the Midwestern U.S., while La Niña would typically cause a wet period in that area. La Niña often causes drought conditions in the western Pacific; flooding in northern South America; mild wet summers in northern North America, and drought in the southeastern United States.

Sunday, July 15, 2012




EL NINO

The
 El Niño phenomenon is an abnormal weather pattern caused by the warming of the Pacific Ocean. It is characterized by extreme climatic changes - world-warming along South America, torrential rains in North America, extreme temperature rise and drought in Southeast Asia and Australia. El Niño occurs every two to seven years.
El Niño is Spanish for "the boy" and refers to the Christ child, because periodic warming in the Pacific near South America is usually noticed around Christmas. "La Niña," on the other hand, is Spanish for "the girl." El Nino is also known as the southern oscillation.

El Niño phenomena dramatically affects the weather throughout the world. Among other weather anomalies, El Niño events are responsible for:
  •       A shift of thunderstorm activity eastward from Indonesia to the south Pacific, which leads to abnormally dry conditions and severe droughts during both warm and cold seasons in Australia, the Philippines, Indonesia, southeastern Africa and Brazil.
  •       During the summer season the Indian monsoon is less intensive than normal and therefore it is much less rainy than usual in India.
  •       Much wetter conditions at the west coast of tropical South America.
  •       El Niño impacts on the United States, North America and the Atlantic regions include:
  •       Wetter than the normal conditions in tropical latitudes of North America, from Texas to Florida, including more intensive wintertime storms.
  •       Extreme rainfall and flooding events in California, Oregon and Washington.
  •       Much milder winters and late autumns in northwestern Canada and Alaska due to pumping of abnormally warm air by mid-latitude low pressure systems.
  •       Below normal hurricane/tropical cyclone activity in the Atlantic (however, their strength is not limited by El Niño).
  •     Drier than normal North American monsoons, especially for Mexico, Arizona and New Mexico.
  •       Drier than normal autumns and winters in the U.S. Pacific Northwest.



What Causes El Niño?
The warming of the Pacific occurs as a result of the weakening of trade winds that normally blow westward from South America toward Asia.
Global Wind Patterns: wind belts of the general circulation
The global wind pattern is also known as the "general circulation," and the surface winds of each hemisphere are divided into three wind belts:
Polar Easterlies: From 60-90 degrees latitude.
Prevailing Westerlies: From 30-60 degrees latitude (aka Westerlies).
Tropical Easterlies: From 0-30 degrees latitude (aka Trade Winds).

Sunday, July 01, 2012


Tail-end of a Cold Front

              A cold front is defined as the leading edge of a cooler mass of air, replacing (at ground level) a warmer mass of air, which lies within a fairly sharp surface trough of low pressure. It forms in the wake of an extratropical cyclone, at the leading edge of its cold air advection pattern, which is also known as the cyclone's dry conveyor belt circulation. Temperature changes across the boundary can be as much as 50F (30C). When enough moisture is present, rain can occur along the boundary. If there is significant instability along the boundary, a narrow line of thunderstorms can form along the frontal zone. If instability is less, a broad shield of rain can move in behind the front, which increases the temperature difference across the boundary. They are stronger in the fall and spring transition seasons, and weakest during the summer. When they catch up with the preceding warm front, the portion of the boundary which does so is then known as an occluded front.

          The cooler and denser air wedges under the less-dense warmer air, lifting it. This upward motion causes lowered pressure along the cold front and can cause the formation of a narrow line of showers and thunderstorms when enough moisture is present. On weather maps, the surface position of the cold front is marked with the symbol of a blue line of triangles/spikes (pips) pointing in the direction of travel. A cold front's location is at the leading edge of the temperature drop off, which in an isotherm analysis would show up as the leading edge of the isotherm gradient, and it normally lies within a sharp surface trough. Cold fronts move faster than warm fronts and can produce sharper changes in weather. Since cold air is denser than warm air, it rapidly replaces the warm air preceding the boundary.
In the northern hemisphere, a cold front usually causes a shift of wind from southwest to northwest clockwise, also known as veering, and in the southern hemisphere a shift from northeast to southwest, in a clockwise manner

Front boundary of 2 air masses, found in mid-latitudes is the later portion of an advancing or leading edge of a steep cold wedge of air characterized by cumulus and cumulonimbus clouds with frequent precipitation in the form of heavy shower

A cold front is the front of a cold air mass, or basically a giant bubble of relatively cold and dry air. A front in general is an area of disturbed weather at the front of an air mass (and, by definition, the back of the air mass it is pushing out of the area
·         The tail end of a front is the back edge of that frontal boundary, not the back of the air mass itself.

Manila, Philippines
A tail-end of a cold front affecting Northern and Central Luzon is causing rain in parts of the country, including Metro Manila, the Philippine Atmospheric Geophysical and Astronomical Services Administration said Monday.
But the rain is expected to ease  tonight or Tuesday morning, said Pagasa weather forecaster Jori Loiz.
A cold front is formed from the replacement of cold air mass with warmer air mass, said Loiz.
In its 5 a.m. bulletin, Pagasa said Luzon and Mindanao would experience mostly cloudy skies with scattered rainshowers and thunderstorms becoming cloudy with widespread rains over Northern Luzon and the eastern section of Southern Luzon which may trigger flashfloods and landslides, it said.
The rest of the country will be partly cloudy to cloudy with isolated rainshowers or thunderstorms.
Moderate to strong winds blowing from the northeast and east will prevail over Luzon and coming from the east over the rest of the country. The coastal waters throughout the archipelago will be moderate to rough, the state weather bureau said.






Saturday, June 30, 2012


MONSOON

  • Monsoon is traditionally defined as a seasonal reversing wind accompanied by corresponding changes in precipitation, but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea. Usually, the term monsoon is used to refer to the rainy phase of a seasonally-changing pattern, although technically there is also a dry phase.


  •  'Monsoons' is derived from the Arabic word "mausim" which means season and it is a weather phenomenon which is common to Asia. Monsoons are defined as winds that change their direction with the change of seasons. Monsoons are seasonal reversals of wind direction that affect the Indian sub-continent and are caused by the following factors:

1. Extreme heating and cooling of large land masses in relation to the surrounding sea, which impacts on pressure and winds.
2. The Himalayas that is high enough to interfere with general atmospheric circulation.
3. Movement northwards of the ITCZ in summer in the northern hemisphere.





  • Also defined as a  wind blowing part of the year from one direction, alternating with a wind from the opposite direction; -- a term applied particularly to periodical winds of the Indian Ocean, which blow from the southwest from the latter part of May to the middle of September, and from the northeast from about the middle of October to the middle of December.



  • A monsoon is a seasonal prevailing wind which lasts for several months. monsoonal rainfall is considered to be that which occurs in any region that receives the majority of its rain during a particular season, and so monsoons are referred to in relation to other regions such as in North America, Sub-Saharan Africa, Brazil and East Asia. Monsoons are caused by the larger amplitude of the seasonal cycle of land temperature compared to that of nearby oceans. This differential warming happens because heat in the ocean is mixed vertically through a "mixed layer" that may be fifty metres deep, through the action of wind and buoyancy-generated turbulence, whereas the land surface conducts heat slowly, with the seasonal signal penetrating perhaps a metre or so. As monsoons have become better understood, the term monsoon has been broadened to include almost all of the phenomena associated with the annual weather cycle within the tropical and subtropical land regions of the earth.


  • The Asian monsoons may be classified into a few sub-systems, such as the South Asian Monsoon which affects the Indian subcontinent and surrounding regions, and the East Asian Monsoon which affects southern China, Korea and parts of Japan.


Causes of Monsoon





Monsoons are an annually recurring weather phenomenon, triggered by the earth’s tilt in relation to the sun. Although they return every year, it is still impossible to tell the timing, duration, and quantity of rain each season, a fact that leaves impacted areas without accurate storm information. Monsoons are set by land and sea temperature differences. Land reflects the sun’s rays, heating air over land more rapidly. Water is able to absorb a lot of heat without itself changing temperature much, so air over water stays relatively cooler.

This fact is prevalent in Asia because the northern hemisphere has so much more land than the southern hemisphere, which is mostly ocean. During he summer, the earth is tilted at such an angle that the sun’s rays shine more directly on the northern hemisphere. The heat is absorbed by the land masses, warming the air above it. The hot air rises, and cooler ocean air rushes inland from the southern hemisphere to replace it. As it moves, it carries moisture with it, releasing it over land as the summer monsoon (also known as southwest monsoon). The cycle continues as the cooling air creates precipitation and releases more energy. This energy then heats the air, which rises and flows back to the sea, cools, descends, and rushes back to land to replace more warm, rising air. This monsoon is centered over continental Asia.
There is also a winter monsoon (also known as northeast monsoon), created during the winter when most of the sun’s rays shine on the southern hemisphere. During this season, the continents are cooler than the water, which retains absorbed heat. The air reverses circulation, with warm air rising over the oceans and cooler land air, called “cold surges,” rushing in to replace it. The cold surges pick up warm moisture as it travels across tropical waters only to release them over Indonesia, northern Australia, Sri Lanka, and the east Indian coast.