Credit: http://www.astrophoto.fr/
Northeast Ohio weather and science blog covering severe storms, long term outlooks, climate, behavioral meteorology, technology and other observations
Saturday, May 22, 2010
Wednesday, May 19, 2010
30th anniversary of Mt. St. Helens Eruption
The Mount St. Helens volcanic eruption is the most famous volcanic eruptions in US history. The eruption and ensuing pyroclastic flow killed 57 people and dropped the elevation of the summit more than 1300 feet. The amount of ash debris was almost 1 cubic mile in volume. Imagine a box a mile on each side? That's alot of material. A look at Mount St. Helens before the eruptions.
What about the phrase "pyroclastic flow". What does this mean? It is term describing the flow of hot gas and collective material from the volcano that flows down the side of the mountain. It can reach speeds of 450 miles per hour and temperatures of close to 2000 degrees and has been know to cross bodies of water for miles. Its these pyroclastic flows that cause the majority of the damage in volcanic eruptions. A look a year after the eruption. Notice the crater in the middle.
A satellite timelapse over the last 30 years showing the evolution of the mountain since the eruption.
Tuesday, May 18, 2010
What is this Loop Current in the Gulf?
image credit: "uscgd8" at flickr
The Loop Current has been making the news since the Gulf Oil Spill occurred a few weeks ago.
Now that the Oil Spill is drifting east, the Loop Current is now playing a pivotal role in where the oil spill travels.
What is this The Loop Current? is an ocean current that resides between the Yucatan Peninsula and Cuba. It originates in the Caribbean Sea, flows out into the Gulf of Mexico and loops around southeastward into the Florida Keys and into the Bahamas. Its a few hundred miles wide and runs more than a 1000 feet deep.
According to the Cooperative Institute for Marine and atmospheric studies, the Loop Current draws its waters from the Yucatan Current, which is ultimately fed by the Caribbean Current, Guiana Current and North Equatorial Current. This provides a vital link between North Atlantic and South Atlantic waters. Here is a graphic showing the ocean currents around the planet from the 1940s. The animation below shows the currents in action.
Althought this might be the first time you've heard about the Loop Current, you don't have to go far back in
history to find that the Loop Current was involved in another natural disaster. Remember Hurricane
Katrina? The Loop Current was directly responsible for its rapid intensification into the historic Category 5
hurricane we all remember. Notice how the track of Katrina and Rita coincides with the Loop Current.
Katrina wasn't the first hurricane to feed off of this moisture/heat rich Loop Current. Hurricane Rita in 2004 intensified over the loop current as indicated above Hurricane Camille in 1969, the last hurricane to directly hit New Orleans prior to Katrina interacted with "The Loop". Hurricane Wilma in 2005 and Hurricane Allen in 1981 among others have greatly intensified due to the loop current.
Back to the oil spill. This same Loop Current that played a direct role in Hurricane Katrina's development
is directly involved with the track of the oil in the next severe weeks.
How can we accurately forecast the movement of the oil spill? For years, the National Oceanic and
Atmospheric Administration has been doing research on the ocean and its movement. NOAA launches surface buoys to gain valuable data on the oceans and their behavior. Here is the track of ALL of the buoys from 1978 to 2003.
You can see how the current behave near the loop current and how the current ntersects with the Gulf Stream around Florida and up the eastcoast. Expect the Loop Current to strengthen hurricanes this season. More on that later this summer.
Monday, May 17, 2010
Rainy Next 48 Hours
The grass is much greener now that we've had a few weeks of above normal rainfall. The trees are almost at their peak and the late spring flowers are about ready to bloom. Although the weekend was more or less dry and comfortable, the next southern system is now over the area and promises to produce yet another round of rainy weather over the next 36 hours.
To answer this, we have to go to the tropics and a term called: PRECIPITABLE WATER
If you were to squeeze out ALL of the water vapor in the clouds in the form of rain, that is called PRECIPITABLE WATER. The higher the PW, the more moisture in the atmosphere. Higher moisture values are represented with warmer colors on the image here from the National Oceanic and Atmospheric Administration.
The band of red and yellow shows the higher pool of moisture over the tropics. Every once in a while, a tongue of moisture will stream north through the central US. Often in the spring, this tongue of tropical moisture will make it all of the way into northern Ohio. Its this moisture source that is responsible for the frequent rains over the last two weeks. Expect more this week.