Why South China sea has so many islands, reefs and low tide rocks ?

upsc_cracker

International Question

After reading tons of literature regarding several groups of islands and reefs located in South China Sea I wonder

Why South China sea has so many islands and low tide rocks ?
Why South China Sea has got so many reefs ?

sss_2503

Japanese sea (South China sea) is found above convergence of 3 tectonic plates: Eurasian plate, Pacific plate and Philippines plate. So over the years due to folding and faulting many islands have been formed around these plate boundaries

For reef formation refer to @Babur answer

upsc_cracker

agreed volcanism responsible for creation of islands but what explains

So many mid sea low tide sand bars because AFAIK volcanic islands can create rocky islands.
If someone cites the erosion of islands and other features my counter query how did sand bars got deposited in mid sea why didn't the sea dispressed the sand before they accumulated as Sand bars

@Babur @sss_2503

trying_tobawesm

@upsc_cracker @Babur

regarding ur query on how can there be sandbars,,why they did not get washed away?
- I am making these up, based on facts of south china sea

- One, it could be perhaps the waves are not even strong enough or break these sand bars,,,,for example, if a weed sea (sargasso sea) can be created in atlantic due to cyclical motion of currents, then of course sand can stay in south china sea coz waves do not want to take it anywhere, they are just too weak,,,

- second, I can also claim that these formations are stable coz the chinese are dredging the sand from other parts and putting on these sand bars,,so it means they understand that waves are not going to take it anywhere,,,,,

- third, i think what would have happened is that volcano created the rocks,,,around the rocks formed the atoll,,,now first waves deposited water and sand in between this,,creating a lagoon,,,then it wasted away the outside part of rock and atoll,,nd u are left with a sand bar

- fourth, i believe it is a very shallow and lake kind of thing this south china sea, so do not even compare it with features u will think in terms of pacific ocean,,,

deusAdeeb

I am not opening a new thread for this doubt. SOrry for that

Why does the Indian ocean become hottest in October rather than June/July when we would expect it to have the maximum temperature ? I read online that it is for the same reason that maximum day temperatures are found at mid-noon on land even though the sun is directly over head at the noon.

I am unable to figure it out.

@upsc_cracker @Babur @Etat dada @Neyawn . Can any of you please help ?

trying_tobawesm

@deusAdeeb

in june/july the sun is overhead tropic of cancer,,thus much over indian mainland,,,,,,afterwards it starts going down over the indian , equator and onto australia,,,
shifting of temperature belts with movement of sun is the answer

deusAdeeb

@Babur

While one would intuitively expect tropical cyclones to peak right at the time of maximum solar radiation (late June for the tropical Northern Hemisphere and late December for the tropical Southern Hemisphere), it takes several more weeks for the oceans to reach their warmest temperatures. The atmospheric circulation in the tropics also reaches its most pronounced (and favorable for tropical cyclones) at the same time. This time lag of the tropical ocean and atmospheric circulation is analogous to the daily cycle of surface air temperatures - they are warmest in mid-afternoon, yet the sun's incident radiation peaks at noon.

http://www.aoml.noaa.gov/hrd/tcfaq/G4.html

rogerthat

@Babur

While one would intuitively expect tropical cyclones to peak right at the time of maximum solar radiation (late June for the tropical Northern Hemisphere and late December for the tropical Southern Hemisphere), it takes several more weeks for the oceans to reach their warmest temperatures. The atmospheric circulation in the tropics also reaches its most pronounced (and favorable for tropical cyclones) at the same time. This time lag of the tropical ocean and atmospheric circulation is analogous to the daily cycle of surface air temperatures - they are warmest in mid-afternoon, yet the sun's incident radiation peaks at noon.

http://www.aoml.noaa.gov/hrd/tcfaq/G4.html

bhai ispe mujhe doubt hai ki bay of bengal october mein warmest hota hoga.but cyclone october mein kyun aate hain june/july mein kyun nahi uska reason common sense se ye lagta hai ki june /july mein land is so hot ki it has much lower pressure than sea..so cyclone ke liye required low pressure sea pe hai nahi..jab convective process kland pe ho raha hai to cyclone banna bahut difficult hai..by october when land has cooled down and pressure above sea is reduced tab you have all the three conditions- lowpressure to provide convection and vorticity,air is still warm and moisture is always there above sea..to cyclone grequency peaks in october..baaki koi geo waala ho to bataye ki sahi hai ki nahi ye...

baaki tumhara afternoon mein sun overhead but max temperature around 3 o clock ka reason wahi hai jo iska hota hai ki minimum temperature is around half an hour after sunrise...once the sun has risen and it starts heating ,temperature begins to rise on land due to insolation which is far greater than heat loss ddue to radiation by land...strength of insolation keeps increasing till noon after which it decreases but still it is greater than heat loss due to radiation...it is only after sometime after noon that rate of heat gained through radiation is equal to rate of heat lost due to radiative cooling...after this reverse starts to happen ...same principle is applicable on global scale why january is coldest when sun is at max angle in december..@deusAdeeb

deusAdeeb

@rogerthat Brilliant ! ^:)^