This week we are getting on a journey of exploring weather,
especially extreme weather. I'm going to break away from my regular home country
as a topic and head to Asia this time.
China, a country in east Asia with a
population of 1.4 billion and the second largest state by land area of
3.7 million square miles. the climate in China varies greatly from south to north,
especially in winter when dry and cold winds, blowing from Siberia and the
Mongolian Plateau, lead to a huge temperature gap between south (above 0℃)
and north (far below 0℃) China. The country climate is divided into six categories as follows:
tropical, subtropical, warm-temperate, temperate, cold-temperate, and
Qinghai-Tibet Plateau temperate zone. Most of the country lies in the northern
temperate zone, which is characterized by warm climate and well-defined
seasons, being suitable for habitation. https://www.chinatravel.com/facts/china-climate.htm
Before we get into the details of china's extreme weather, let me give you an introduction of what's extreme weather is, and what type of weather do china constantly face. Extreme weather refers to weather phenomena that
are at the extremes of the historical distribution and are rare for a
particular place and/or time, especially severe or unseasonal weather. Such
extremes include severe thunderstorms; severe snowstorms, ice storms, blizzards,
flooding, hurricanes, and high winds, and heat waves. https://www.ncbi.nlm.nih.gov/books/NBK45750/
More specifically in extreme weather, there is what lately we've heard a lot about; Hurricanes, cyclones, and typhoons that are happening in different corners of the world, but what are they.? In a simple answer, they are all the same weather
phenomenon; we just use different names for these storms in different places.
In the Atlantic and Northeast Pacific, the term “hurricane” is used. The same
type of disturbance in the Northwest Pacific is called a “typhoon” and
“cyclones” occur in the South Pacific and Indian Ocean.
China is well known for it industrial advances and
a booming economy, but also for its direct path for powerful typhoons.Typhoons hit China more often than any other country in
Asia. On the average, about 7 or 8 land each year. Since 2015 and 2016 has an
unusually strong El Nino weather pattern, there has been an unusual number of
strong typhoons landing in or coming near China. the Swiss Re's insurance
company ranks Shanghai as 8th riskiest and the Pearl River Delta 3rd riskiest
for major natural disaster in the whole world. Some other cities in the world
face earthquakes, but China's coastal Shanghai Region and Guangzhou.
- Note: During an El Nino - when the central Pacific is warming - there are fewer Atlantic storms. El Ninos shift where storms form, but not the number, for the northwest Pacific and the southwest Pacific. The central Pacific gets more storms during El Nino and the year after.
To explain a typhoon, is a large, strong, tropical cyclone. A cyclone is
a low pressure area spinning counterclockwise and holding rising warm air that
forms over warm water in the western Pacific Ocean. The winds from a typhoon
can reach from 75 - 150 MPH. A super typhoon’s winds can reach up to 150+ MPH.
There are three main ingredients of a
typhoon. 1. Warm water. 2. Moisture. 3. Inward spiraling winds. If the right conditions persist long enough, they can combine to produce
the violent winds, incredible waves, torrential rains, and floods.
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Typhoons start off as tropical thunderstorms. The strong
winds pull in moisture from the oceans.
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The thunderstorms convert the moisture into heat. The heat
causes more air to flow to the centre of the storm causing evaporation.
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All the heat and air flow toward the eye creating the
typhoon.
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As I briefly talked about china's typhoons dilemma. This figure below shows the start of tropical cyclone records in 1946. The
last ''level No 10'' storm was Vicente, which hit in 2012. The No 10 signal was
issued on July 24 and lasted for close to three hours. At least 138 people were
injured.
Among them, Wanda, a typhoon which hit Hong Kong from late
August to early September in 1962, was the deadliest. Wanda escalated to the
level of a “super typhoon”, meaning its maximum sustained winds near the centre
of the storm reached 185 km/h or above. At least 130 people were killed and 53
people were reported missing.
http://www.scmp.com/news/hong-kong/health-environment/article/2107903/brief-history-hong-kong-typhoons
China's methods of staying safe and mitigate an extreme weather
scenario, in this case typhoons in the areas of Hong Kong, Macau,
Shanghai and Guangzhou they general use a similar system of warning. If a
typhoon approaches, there are four warning signals that are broadcast for the
public and it goes as follow:
- Signal blue: The signal is used when a storm with winds of 31 mph (50 kph) or slightly lower is 24 hours from the city and approaching. It is a warning to keep alert.
- Signal yellow: A storm with winds of about 41 mph (66 kph) may arrive within 24 hours.
- Signal orange: A storm with winds of about 58 mph (95 kph) is predicted to arrive within 12 hours. A signal orange might last for a day or less. This warning gives the public a chance to prepare their home or go to a safe place and all schools are closed.
- Signal red: Expect a typhoon with winds of at least 72 mph (117 kph) to arrive within 6 hours. A signal red is rare. Destructive force is expected. Flights and bullet trains are generally canceled. cities are mainly endangered by typhoons.
In case of a signal orange, make sure that your shelter can
withstand possible gale or typhoon force winds and is not in a flood prone
place. Consider leaving the city or getting a higher room in a hotel. You'll
have a little time to move to a safer location. Stock some water and food to
last a day or two, and have a portable radio, flashlights, batteries, and
candles ready.
If a typhoon hits the area, then stay away from windows. If
you are on a bottom floor of a hotel or other building near sea level, try to
move up to a higher floor to avoid any flooding. In case of a category 5
typhoon, the storm surge can rise more than 30 feet or three stories high, so
try to get higher than this. Listen to public flood warnings.
After typhoon:
- Be sure that the house/ building is safe and stable before you enter.
- Beware of poisonous animals like snakes that may have entered your house.
- Watch out for live wires or outlet immersed in water and report damaged electrical cables and fallen electric posts to authorities.
And as usual I'll finish my blog by a video. This one is from a news report about Typhoon Meranti that hit china in 2016, show casing the destructive force a typhoon can be.
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