Tuesday, February 22, 2011

Another Earthquake in New Zealand

A magnitude-6.3 earthquake today hit Christchurch, New Zealand. Although less powerful than the one that struck in September last year, it is much more devastating. Many buildings in the city were demolished, including its iconic cathedral. The casualty toll currently stands at 63, but is expected to climb above 100 in the next few days. Today's earthquake struck 45km west of the city and is only 5km below the surface. This aftershock is much closer than the quake that registered five months earlier. My condolences to those affected and I hope the city can rebuild from this unfortunate episode!


-PTS

Friday, February 18, 2011

Watson Beats Human Champs on Jeopardy!

It is official: IBM's Watson, a supercomputer equipped with terabytes of RAM, was crowned champion of champions on Jeopardy this week. It smashed the show's two most accomplished human Jeopardy contestants ever by a mile. Prior to this challenge, Ken Jen and Brad Rutter both won over $3M USD on Jeopardy!

It is amazing how far artificial intelligence has come over the years.  I was especially impressed with Watson's ability to interpret the play of words often found in Jeopardy-styled clues (or answers). Apart from the occasional mishaps when it completely missed the mark, Watson did extremely well even in categories like "Familiar Sayings" that require a certain level of intuition.  Enjoy this clip on the final 10 minutes of the competition:


In 1997, IBM's Deep Blue defeated fellow human grand masters like Garry Kasporav. Fourteen years later, we have a Jeopardy champ that does not require food or sleep.  One cannot help but wonder what next to expect in the world of A.I.  Whatever it is, let it not be the terminators from SkyNET who will turn on us and cause a nuclear holocaust!


-PTS

Sunday, February 6, 2011

Tropical Cyclones

Tropical Cyclone Yasi hit Queensland, Australia a few days ago, causing millions of dollars in damages.  The silver lining in this unfortunate episode, is that it missed areas of concentrated populations. It is worth noting that the sheer size of the weather system would have wreaked much more havoc had it hit elsewhere.  

What is a Tropical Cyclone
A tropical cyclone is essentially a spiraling mass of wet air centred around an area of low atmospheric pressure most commonly known as the "eye". On the ocean, a cyclone is continually fed as evaporated water from the ocean surface condenses, releasing more heat as the air current rises. Owing to the Coriolis effect, a cyclone spins counterclockwise in the Northern Hemisphere and clockwise in the Souther Hemisphere.

Strength Categories
According to the Saffir-Simpson Hurricane Scale, Yasi was a category 5 cyclone, the strongest of its kind. It reached wind speeds of 250km/h, and storm surges of greater than 18ft.

Category
Wind Speed mph
(km/h)
Storm Surge ft
(m)
Five
≥ 156
(≥ 250)
> 18
(> 5.5)
Four
131–155
(210–249)
13–18
(4.0–5.5)
Three
111–130
(178–209)
9–12
(2.7–3.7)
Two
96–110
(154–177)
6–8
(1.8–2.4)
One
74–95
(119–153)
4–5
(1.2–1.5)

Hurricanes and Typhoons
Cyclones are more commonly known as hurricanes in the North Atlantic and the Northeast Pacific. The word hurricane maybe derived from the Mayan storm god, Huracan. In the Northwest Pacific and east Asia, cyclones are called typhoons. This word may have originated from the Greek mythological monster, Typhon, often associated with storms. The phonetics behind the word typhoon translates well into "strong winds" in Chinese and Japanese. Hence, it is also used in these regions.

Naming Conventions
Meteorology centres throughout the world have their own naming conventions for cyclones, hurricanes and typhoons.  In most areas, a set of female names in alphabetical order is often pre-assigned before the season to name these natural phenomena. In Australia, cyclone names have alternated between male and female names since 1976. Cyclones are sometimes renamed when it moves from one region to another. Names are also recycled every few years, but devastating storm names like Hurricane Katrina of 2005 are usually retired to note historic significance.


-PTS