5377_wei
TRANSCRIPT
Shih-Hsuan Wei
Introduction
It’s been few years for me living in Lubbock, Texas
after left home in Taiwan. I have always felt that
summers never end in Lubbock, in which it have
much more sunlight when I was in Taiwan. Is it an
illusion for me because I have not gone back to
Taiwan in summer time in the past years? Or it is an
actual scientific proof that it is the difference. So the
question I want to ask is “In summer 2010, did
Lubbock, Texas have more sunlight than Taipei,
Taiwan?” In particular, I will only determine the
summer time in 2010 in both places. What I mean
summer time is only from June 1st to August 31st.
Before starting collecting some data, let me begin with the geographies of two different cities.
Lubbock is a city of
the state of Texas. It
is located in the
northwestern part of
the state, located at
33 33“ N, 101 52” W.
The state of Texas is
1279 km (790 mi)
long and 1244 km
(773 mi) wide of total
696,241 km2 (268,
581 mi2) with the
population of 25 million.
Lubbock. http://en.wikipedia.org/wiki/Lubbock,_TexasViewed 2.23, 2011.
Taiwan, also known as Formosa (Beautiful Island), is an
island situated in East Asia in the Western Pacific Ocean,
and located at 23 30“ N, 121 00” E. The main island of the
group is 394 km (245 mi) long and 144 km (89 mi) wide of
total 35,980 km2 (13, 892 mi2) with the population of 23
million. Taipei city is the capital of the Taiwan, located
northern part of the island.
Taiwan.http://en.wikipedia.org/wiki/Taiwan
Viewed. 2,23, 2011.
Now we have some idea where Lubbock, Texas and
Taipei, Taiwan are. Then we can start finding some
data about sunrise and sunset in both cities in 2010.
The best resource to collect these data is the Naval
Oceanography Portal website
http://aa.usno.navy.mil/data/docs/RS_OneYear.php.
The U.S. Naval Observatory (USNO) provides a
wide range of astronomical data, in particular, you
can find table of sunrise/ sunset for an entire year
for any location in the world.
Start with Lubbock, Texas:
Lubbock, sunrise/set.http://aa.usno.navy.mil/data/docs/RS_OneYear.phpViewed. 2,23, 2011.
Figure 1: Sunrise/set time in Lubbock, Texas in 2010.
Since we only consider the summer time, we will
only look at the data of sunrise/sunset from June 1st
to August 31st in 2010. With a little bid math that we
can obtain the daylight of each day by calculating
the difference between sunrise and sunset
everyday i.e. subtract the sunrise from sunset. For
instance, the daylight on June 1st, 2010 can be
calculated by 1953 – 538 = 1416, i.e. it had a 14 hours and 16 minutes of daylight on June 1st, 2010.
However, let’s look at the daylight of July 1st, 2010.
2002 - 0541 = 1461, there is something odd here. How
would you have 14 hours and 61 minutes? Then we
should modify it a bid. Since 1 hour = 60 minutes. The
following is the correct way to calculate the daylight on
July 1st, 2010.
1. 2002 = 1962 (since 1 hr = 60 min)
2. 1962 – 0541 = 1421
i.e. there was 14 hours 21 minutes of daylight on July 1st,
2010.
So with the tool of Excel and some modification, we come
out the next table. In addition, we only consider the data
from June 1st to August 31 in 2010.
Figure 2: Modification of sunlight in Lubbock, Texas in summer 2010.
After the calculation and modification, we have the
summations of sunlight in June, July and August
respectively in the following.
Figure 3: Summation of sunlight in Lubbock, Texas in summer 2010.
Next, let’s look at daylight in Taipei, Taiwan. We will use
the coordinate as Longitude: W 121 degrees 30 minutes
and Latitude: N 25 degrees 3 minutes, and the time zone
as 8 hours east of Greenwich. (The tiny island in H zone.)
Time Zone Map.http://aa.usno.navy.mil/faq/docs/world_tzones.phpViewed. 2, 23, 2011.
Taipei, sunrise/set.http://aa.usno.navy.mil/data/docs/RS_OneYear.phpViewed. 2,23, 2011.
Figure 4: Sunrise/set time in Taipei, Taiwan in 2010.
There is something weird in the data table. The sun
rose at 2251 and set at 928 on January 1st, 2010 in
Taipei, Taiwan. Does that make any sense? The sun
rise at the night and the sun set in the morning.
What kind of place is that? There must be
something wrong. Nothing is wrong it is because
Taipei, Taiwan is 8 hours ahead of Greenwich. That
means when it is 10:00 am in Greenwich, it is 6:00
pm in Taipei. So the following table is the correct
time after the modification.
Again, we only consider the summer time (June to August).
Figure 5: Sunlight in Taipei, Taiwan in summer 2010.
The following table is the summations of sunlight in June,
July and August in 2010 in Taipei, Taiwan, and the total
daylight from June to August.
Figure 6: Summation of sunlight in Taipei, Taiwan in summer 2010.
Now we have the summation of sunlight in Lubbock,
Texas and Taipei, Taiwan in summer 2011. The
following table represents the difference between
these two cities.
Figure 7: Excel graph shows the sunlight between two cities in summer 2010.
The following excel graph represents the total
sunlight time in Lubbock, Texas and Taipei, Taiwan in summer 2010.
Figure 8: Excel graph shows the total sunlight time in two cities in summer 2010.
As the result came out, the daylight in Lubbock,
Texas was more than in Taipei, Taiwan in
Summer 2010. Thus, what I have felt was right that
summers seem never end in Lubbock, Texas. In the
following, there are some scientific proofs based on
the latitude and longitude in the world, and some
interesting fact about the daylight-saving time
adjustment in the U.S. and in Taiwan.
In general, the length of a day varies throughout the year, and it depends on the latitude.
World map with latitude and longitudehttp://fr.mapsofworld.com/world-maps/world-map-with-latitude-and-longitude.htmlViewed. 2, 23, 2011.
This variation is caused by the tilt of the Earth’s axis
of rotation with respect tot the ecliptic plane of the Earth around the sun.
Earth’s axis. http://blog.xuite.net/wellsli/002/35113257Viewed. 2, 23, 2011.
Because the Earth’s revolution around the sun on
one side, while around its axis. The axis with the
public-axis orbital plane into 66.5 degrees angle,
making the Earth’s movement in orbit, and with
different relative position of the sun that varies the
existence point between the Tropic of Cancer.
Before coming to the U.S., I know the time
difference between the U.S. and Taiwan would be
adjusted for summers and winters. For example, the
time difference between California and Taiwan in
summer is 15 hours, but it becomes 16 hours in the
winter.
When I needed to call my friends in Los Angles,
California, I had to call at midnight in Taiwan, and I’d
have to call around 1 in morning in the winter.
This is because of the daylight-saving time (DST)
adjustment, the summer sunlight has longer time in
higher latitudes. Typically clocks are adjusted
forward one hour in the spring and are adjusted
backward in autumn . It is the practice of
temporarily advancing clocks during the
summertime so that afternoons have more daylight
and mornings have less.
Currently, there are about 110 countries around the
world using daylight-saving time. Since the season
in southern hemisphere is opposite to the northern
hemisphere, DST are adjusted oppositely during the
seasons. The countries in low-latitude have
relatively fixed duration of sunshine, there is no
need for DST. Does the small island like Taiwan
have DST? No, no any more. But there were some
researches said Taiwan had DST before.
Actually, Taiwan implemented DST from 1945 to
1961, revoked DST from 1962 to 1973, reinstated
1974 to 1975, and abandoned DST from 1976
onwards.
There were two main reasons behind it:
1. Time adjustment caused trouble in society.
2. The limitation of DST because Taiwan is located
in the subtropical region.
The oil crisis in 1970s, the government of Taiwan
had a brief resume of DST system, but it caused a
lot of grievances then it quickly canceled. Actually,
Taiwan implemented DST from 1945 to 1961,
revoked DST from 1962 to 1973, reinstated 1974 to
1975, and abandoned DST from 1976 onwards. But
the so-called grievances, it were most the product
of the bureaucratic system.
Therefore, people living in Taiwan do not need to
adjust the clock with the seasons. Although I have
calculated the time difference with the winter and
summer between Taipei, Taiwan and other cities
around the world before coming to the U.S., but it
has been very interesting to me to experience the daylight-saving time adjustment.
References
Day length. Retrieved February 25, 2011, from
http://en.wikipedia.org/wiki/Day_length .
Geographic Names Information System. Retrieved February 23, 2011,
from
http://geonames.usgs.gov/pls/gnispublic/f?p=154:1:413510313315132
Geography of Lubbock, Texas. Retrieved February 22, 2011, from
http://en.wikipedia.org/wiki/Lubbock,_Texas.
Geography of Taiwan. Retrieved February 22, 2011, from
http://en.wikipedia.org/wiki/Geography_of_Taiwan.
Latitude and Longitude. Retrieved February 23, 2011, from http://blog.xuite.net/wellsli/002/35113257.
References
Map of World.com. Retrieved February 21, 2011, from
http://fr.mapsofworld.com/world-maps/world-map-with-latitude-and-
longitude.html .
National Geospatial-Intelligence Agency. Retrieved February 22, 2011,
from
http://earth-info.nga.mil/gns/html/index.html.
National Science Teachers Association. Retrieved February 22, 2011,
from
http://learningcenter.nsta.org/?lid=tnavhp.
U. S. Naval Observatory. Retrieved February 24, 2011, from
http://aa.usno.navy.mil/ data/.
Time difference between Taipei and Greenwich. Retrieved February 23,
2011, from http://www.happyzebra.com/timezones-worldclock/difference-between-Taipei-and-Greenwich%20Borough.php.