Friday, November 26, 2010

*~*~Global Warming~*~*

-GLOBAL WARMING CONTINUED-

What can we do to help Earth?
The evidence that humans are causing global warming is strong, but the question of what to do about it remains controversial.
Even if we stopped emitting greenhouse gases today, the Earth would still warm by another degree Fahrenheit or so. But what we do from today forward makes a big difference.  Depending on our choices, scientists predict that the Earth could eventually warm by as little as 2.5 degrees or as much as 10 degrees Fahrenheit.



Is this possible?
Many people and governments are already working hard to cut greenhouse gases, and everyone can help!
Researchers at Princeton University have suggested one approach that they call "stabilization wedges." This means reducing Green House Gases emissions from a variety of sources with technologies available in the next few decades, rather than relying on an enormous change in a single area.  They suggest 7 wedges that could each reduce emissions, and all of them together could hold emissions at approximately current levels for the next 50 years, putting us on a potential path to stabilize around 500 ppm.
There are many possible wedges, including improvements to energy efficiency and vehicle fuel economy, and increases in wind and solar power, hydrogen produced from renewable sources, bio fuels (produced from crops), natural gas, and nuclear power.  There is also the potential to capture the carbon dioxide emitted from fossil fuels and store it underground—a process called "carbon sequestration."
In addition to reducing the gases we emit to the atmosphere, we can also increase the amount of gases we take out of the atmosphere.  Plants and trees absorb CO2 as they grow, "sequestering" carbon naturally.  Increasing forest lands and making changes to the way we farm could increase the amount of carbon we're storing.
Some of these technologies have drawbacks, and different communities will make different decisions about how to power their lives, but the good news is that there are a variety of options to put us on a path toward a stable climate!




www.environmentnationalgeographic.com

*~*~Global Warming~*~*

-GLOBAL WARNING-

What Causes Global Warming?
Scientists have spent decades figuring out what is causing global warming. The only way to explain the pattern is to include the effect of greenhouse gases emitted by humans.
One of the first things scientists learned is that there are several greenhouse gases responsible for warming, and humans emit them in a variety of ways-
The most come from the combustion of fossil fuels in cars, factories and electricity production. The gas responsible for the most warming is carbon dioxide, also called CO2. Other contributors include methane released from landfills and agriculture, nitrous oxide from fertilizers, gases used for refrigeration and industrial processes, and the loss of forests that would otherwise store CO2.
Different greenhouse gases have very different heat-trapping abilities. Some of them can even trap more heat than CO2. A molecule of methane produces more than 20 times the warming of a molecule of CO2. Nitrous oxide is 300 times more powerful than CO2. Other gases, such as chlorofluorocarbons, have heat-trapping potential thousands of times greater than CO2. But because their concentrations are much lower than CO2, none of these gases adds as much warmth to the atmosphere as CO2 does.
In order to understand the effects of all the gases together, scientists tend to talk about all greenhouse gases in terms of the equivalent amount of CO2. Since 1990, yearly emissions have gone up by about 6 billion metric tons of "carbon dioxide equivalent" worldwide, more than a 20% increase!




What effects does this have on Earth?
The planet is warming, from North Pole to South Pole, and everywhere in between. Globally, the mercury is already up more than 1 degree Fahrenheit (0.8 degree Celsius), and even more in sensitive polar regions. Signs are appearing all over Earth!
Some impacts from increasing temperatures are already happening.
  • Ice is melting worldwide, especially at the Earth’s poles
  • The decline of penguins on Antarctica have fallen from 32,000 breeding pairs to 11,000 in 30 years
  • Sea level rise became faster over the last century.
  • Some butterflies, foxes, and alpine plants have moved farther north
  • Precipitation has increased across the globe
  • Spruce bark beetles have boomed in Alaska and chewed up 4 million acres of spruce trees
Other effects could happen later this century, if warming continues-
  • Sea levels are expected to rise between 7 and 23 inches
  • Hurricanes and other storms are likely to become stronger
  • Plants could bloom earlier than their pollinating insects become active
  • Floods and droughts will become more common
  • Less fresh water will be available
  • Some diseases will spread, such as malaria carried by mosquitoes
  • Ecosystems will change—some species will move farther north or become more successful; others won’t be able to move and could become extinct


Global warming solutions...continued in my next blog

Monday, November 15, 2010

*~Sonic Boom~*

*~SONIC BOOM~*

What is it?
A shock wave caused by an object moving at supersonic speeds, heard as a loud boom!
 You can learn about sonic booms by looking at the wakes boats leave in the water.
If you toss a pebble in a pond, little waves will form in concentric circles and spread away from the point of impact.
If a boat travels through the pond at 3 to 5 miles per hour, little waves will propagate in the same way both ahead of and behind the boat, and the boat will travel through them.
If a boat travels faster than the waves can propagate through water, then the waves "can't get out of the way" of the boat fast enough, and they form a wake.
A wake is a larger single wave.
It is formed out of all the little waves that would have propagated ahead of the boat but could not.





When an airplane travels through the air, it produces sound waves.
If the plane is traveling slower than the speed of sound (700-750 mph), then sound waves can spread ahead of the plane.
If the plane breaks the sound barrier and flies faster than the speed of sound, it produces a sonic boom when it flies past.
The boom is the "wake" of the plane's sound waves.
All of the sound waves that would have normally spread ahead of the plane are combined together so at first you hear nothing, and then you hear the boom they create.
In conclusion, it is just like being on the shore of a smooth lake when a boat speeds past.
There is no disturbance in the water as the boat comes by, but eventually a large wave from the wake rolls onto shore.
When a plane flies past at supersonic speeds the exact same thing happens, but instead of the large wake wave, you get a sonic boom.


How is it created?
  -They are created mostly by objects traveling at speeds that exceed the speed of sound, known as Mach 1.
  -Mach is named after an Austrian physicist Ernst Mach who studied sound
  -Mach 2 travels at twice the speed of sound
FACTS

Wednesday, November 3, 2010

~Alaska Climate Continued~

ALASKA CONTINUED...

 

Daylight & Darkness in Alaska
From mid May to August, many Alaskans live in near constant daylight. When we lived in Fort Wainwright, we used to use black curtains to keep that sunlight out at night.

This phenomenon, known as the Midnight Sun, reaches as far south as Fairbanks and Anchorage.
Every year Fairbanks has a run called the Midnight Sun Run. The run begins at 10 pm  and finishes once everyone completes 6.2 miles. It was such a fun run! All the locals would gather and cheer you on & have water, powerade & fruit stands for you on the way!

As far as darkness goes in Alaska, at the very top of the state, there is a two-month winter period in which the sun doesn't rise. But that's the extreme, and winter's long nights get shorter the farther south you are in Alaska.  
 The winter's could seem gloomy, but there's fun things to do in the winter too. We attended an ice sculpture event where you can walk into houses made out of ice, sit on ice unicorns and even go on ice slides! You must take caution and wear the right clothing because colder seasons, can increase the danger of frostbite and hypothermia at low temperatures!


Alaska Snowfall Records!
Thompson Pass, a popular extreme ski and snowboard area north of Valdez, once received a record 974.5" of snow during the winter of 1952-1953.
Thompson Pass recorded 62" of snow during one single 24 hour period in December, 1955. In February of

The deepest recorded snow pack in Alaska, and the deepest in all of North America, occurred at Wolverine Glacier on the Kenai Peninsula during the winter of 1976-1977. The depth was 356". That's packed, condensed snow. Almost 30 feet deep!

Barrow, in the dry north, received a record minimum amount of snow during the winter of 1935-1936 of only 3".

Montague Island in 1976 received a record 332.29" of precipitation. That's almost an inch of rain per day!

Barrow received only 1.61" of precipitation during all of 1935.

Alaska stores an immense amount of fresh water in its glaciers. An amazing 75% of the world's fresh water is held in glaciers worldwide and Alaska holds more than its fair share.
Alaska has more than 5,000 glaciers, covering in excess of 100,000 square miles. Alaska has more glaciers than the entire rest of the world combined, excluding the ice fields of Antarctica and Greenland.

Alaska really is a memorable place to visit!

~Alaska Climate~

Alaska Climate



Alaska is our country's northern most state. It's above Canada and close to the North Pole.

When's the best time to visit Alaska?
Mid May to mid September is the preferred time to visit, with June-August being the best.
Not all of the state is as unbearable, cold and miserable year-round as a lot of people believe. Even if you don't have a lot of outdoor experience, guided tours allow you to discover true Alaska wilderness during the day. Whether you prefer to hike on an ice age glacier, explore the wilderness in a "bush" plane or take a dog sled ride, you'll find plenty of options to experience Alaska! The state's many famous rivers, lakes and protected coastal waters offer the chance to experience rafting, kayaking or jet boat rides. Also if you would like to see moose...Alaska is the place to be!


There are actually about six different climates-
1. The Fairbanks area has a wide range, with summers in the 70s-80s F or higher and winters far below 0 F.
2. The Anchorage region has summers in the range of 55-65 F and winters well below freezing.
3. Southeast Alaska-Juneau has summers in the 50s-60s F with mild winters that hover around the freezing mark.
4. The southwest is generally in the 50s F during the summer and below freezing in winter, coupled with lots of wind, snow, sleet and rain.
5. In eastern Alaska-along Canada's border, temperatures average about 60 F in the summer and about 10 to 14 F in winter.
6. Northern Alaska is cool to cold year round, with summer highs generally in the 40s-50s F and winter temperatures well below 0 F (similar to winter in Fairbanks).And just to confuse things, it can drizzle, fog over, gust mightily or chill out even during the peak of summer throughout the state. The climate is part of what makes Alaska such a magnificent place to visit!
Even though, no matter when you go, sweaters, warm clothing and rain gear will be useful.



Friday, October 29, 2010

~MONSOONS~


~MONSOONS~



Those of us who live in Arizona, likely know what to expect when the Arizona monsoon arrives.
Probably the most debated weather event in Arizona is our so called "monsoon". Just the word conjures up visions of rains and widespread flooding followed by heat and drought. The drastic wet/dry combination is the example that most of us learned about in school. However, the monsoon actually occurs in varying degrees, and in Arizona it's marginal, just not as intense as those found in other parts of the world.


DID YOU KNOW?

The term "monsoon" comes from the Arabic "mausim" meaning "season" or "wind shift."

WHAT IS A MONSOON?


A monsoon is a seasonal shift in the prevailing wind direction, that usually brings with it a different kind of weather.
The persistent wind flow is driven by a warm air mass with low pressure at the surface that forms over the continent as it is warmed by the sun.
Air from the relatively higher pressure air mass over the ocean flows toward the low pressure over land.
The most famous monsoon is the Indian summer monsoon, as it affects such a large portion of Asia. In May and June of each year, the dry northerly wind flow over India changes direction, and warm humid air from the Indian Ocean flows from the south, gradually overspreading the Indian subcontinent. Widespread torrential rains, and even severe thunderstorms, accompany the "onset" of the monsoon.
The Indian Ocean version of the hurricane, called a "cyclone", can also occur and move ashore in association with the onset of the monsoon. These cyclones have at times killed thousands of people who live in the low-lying areas along the eastern coast of India and Bangladesh.
A weaker version of this monsoon occurs over the normally dry southwestern United States like Arizona in the later summer when more humid air, accompanied by thunderstorms, invades the region.



WHEN DOES A MONSOON OCCUR IN ARIZONA?




Prior to 2008 the Arizona area monsoon was considered to have started when there were three consecutive days when the dew point averaged 55 degrees or higher. In 2008 the National Weather Service decided to take the guesswork out of monsoon start and end dates. After all, monsoon is a season, and most people should not be concerned with whether or not a particular dust storm was defined as monsoon storm or not. Beginning in 2008, June 15 will be the first day of monsoon, and September 30 will be the last day. Now we can be more concerned with monsoon safety and less concerned with definitions!





WHAT HAPPENS DURING A MONSOON?

Monsoon storms range from minor dust storms to violent thunderstorms. They can even spawn tornadoes, though that is very rare. Typically, Arizona monsoon storms start with heavy winds sometimes resulting in a visible wall of dust hundreds of feet high moving across the Valley. These dust storms are normally accompanied by frequent thunder and lightning often leading to heavy downpours. Monsoon rains average about 2-1/2", about 1/3 of our yearly rainfall.


SAFETY TIPS

WHILE DRIVING

-First SLOW DOWN
-Leave plenty of room between you and the vehicle ahead of you
-Watch carefully for water pooling on the roadway surface as this could cause your vehicle to slide or hydroplane.
-Do not enter an area where the roadway has been closed due to flooding!
-Drive with your headlights on and slowly
-Watch for blowing dust and if possible avoid driving into a dust storm
-If you choose to stop in a dust storm, do not stop on the roadway
-Make sure your vehicle is in good condition
-If you suffer a mechanical breakdown or tire failure, remain calm, slow down, keep the steering straight, and drive the vehicle to a safe area as far from traffic as possible
-ALWAYS wear your safety restraints

IF YOU ARE AT HOME
-Turn off all unnecessary power equipment to reduce the draw on power companies
-Keep batteries, flashlights, and a battery operated radio or TV handy
-Stay off the phone. Even cordless phones can cause a shock when lighting strikes nearby. Use cell phones only if necessary.
-Stay away from plumbing fixtures as lightning can travel along metal pipes.
-Keep away from windows as high winds can blow heavy debris.

 
IF THE POWER GOES OUT
 
-Switch off high usage items such as air conditioners, computers and televisions so there is no danger of overloading your system or damaging these products with voltage fluctuations when power returns.
-Surge protectors for your computer and electronic equipment will provide extra protection.
-Turn on your battery powered radio or TV for information
-Limit how often you open doors so cool air stays inside
-Keep your freezer and refrigerator door closed

 LIGHTNING

Lighting is dangerous no matter where you are. If you find yourself outdoors when lightning strikes:
-Seek shelter immediately
-Stay away from open fields, high land, trees, poles and standing bodies of water
-Do not swim or hold metal objects, including golf clubs and lawn chairs
-Once again stay off your phones and away from plumbing



Wednesday, October 13, 2010

Hurricanes cont.

HURRICANES CONTINUED...

The final stage is the hurricane stage!

Stage 4: Hurricane


Hurricanes have sustained one-minute winds of at least 74 mph, at an elevation of 10 meters. Winds in most hurricanes can become much stronger.

Hurricanes are categorized on a scale of 1 to 5 based on their wind speed, a scale known as the
Saffir-Simpson hurricane wind scale, named after its originators, Herbert Saffir and Dr. Robert Simpson.

In developing tropical cyclones, strong thunderstorms occur. Air pressure drops at the surface of these storms. This low pressure attracts warm moist air from the ocean's surface. The Coriolis force causes the resulting low-level winds to spiral in a counterclockwise direction around the center of the low in the Northern Hemisphere, whereas winds swirl clockwise in the Southern Hemisphere.

Typically, an "eye" forms when the tropical cyclone reaches hurricane strength, but an eye is not necessary for a tropical cyclone to become a hurricane.

Another way to think of a hurricane is as a large heat engine. The fuel is moisture from warm ocean water. The moisture is converted to heat in the thunderstorms that form. Spiral rain bands that surround the tropical cyclone's core help feed the circulation more heat energy.

As air nears the center, it rises rapidly and condenses into clouds and rain. The condensation releases tremendous amounts of heat into the atmosphere. The result is lower surface pressure and strengthening winds.

In this way, the tropical cyclone's engine refuels itself, concentrating its power in a donut-shaped area, called the eye wall, surrounding the center. The eye wall typically contains the strongest surface winds.

Sinking air at the center clears the tropical cyclone of clouds and forms the "eye." Falling surface pressure can occur only if air mass is removed from the circulation center. This is accomplished by wind flowing away from the circulation in the upper atmosphere.


Thankfully with technology today, we have learned so much about hurricanes!

http://www.weather.com/