Pakistan is flooding: 50M people impacted. 1M houses washed away. 1/3 of the country under water. Meanwhile, China is suffering from the worst heatwave in its recorded history. Why? These 2 events are connected.
Interesting. One effect isn't mentioned, which contributes to the problem of China further: When air is loaded with evaporated water it contains also the energy that was necessary to change water from liquid to a gas.
When water condenses while the air gains height climbing the mountains that energy is released again as heat, it keeps the air at the relative dewpoint temperature (which depends on humidity and pressure). As that heated and dried air then flows down on the lee side of the Himalayas it gets under pressure again and heats up as the energy can't be stored as water vapor again - the water was left behind. The air is thus even way hotter than it was when on the pakistani/indian side of the ranges.
It would be worth investigating the impact of insufficient water reservoirs on mass flooding in Pakistan. For example, India does not get regularly flooded to the same extent despite having more rivers than Pakistan and all of them originating from a high gradient somewhere in Karakoram or the Himalayas like Pakistan. There are floods in India almost every season like Pakistan but never to the extent of 1/3 of the country under water. I doubt even 1/10th. The duration of the floods is also not as long as Pakistan where it can often last several months since the only egress available is the Arabian sea. The current floods are the second mass incident in recent years. The 2010 floods affected more than 20 million people. Are there geographic/topological reasons that prevent mass, long-running floods in India? Or merely a lack of investment in a reservoir network.
7000! More than any other country that is not in a polar area! More than China or India, who have the Himalayas and Tibet! Mindblowing... I have read that, although I have looked for a list of glaciers per country and haven't found it. So i'd take that fact with a grain of salt. What is true though is that Pakistan has an astounding number of glaciers.
There are also glaciers that feed water into the rivers in China. Given the heatwave there, why didn’t the increased water from melting glaciers mitigate China’s drought?
Looking at the Map it seems the vast Tibetan plateau (incredible mountainous, but mostly above 4000m elevation) is having ranges and valleys that are running from east to west.
The whole land is very dry and the water that is coming from the glaciers is running to Ladakh and then Pakistan. The plateau ends in the north in another high mountain range (border to China more or less) and that part of China (Xinjiang and Qinghai) are mostly big, dry deserts where a few rivers run to but do not pass through.
Interesting. One effect isn't mentioned, which contributes to the problem of China further: When air is loaded with evaporated water it contains also the energy that was necessary to change water from liquid to a gas.
When water condenses while the air gains height climbing the mountains that energy is released again as heat, it keeps the air at the relative dewpoint temperature (which depends on humidity and pressure). As that heated and dried air then flows down on the lee side of the Himalayas it gets under pressure again and heats up as the energy can't be stored as water vapor again - the water was left behind. The air is thus even way hotter than it was when on the pakistani/indian side of the ranges.
I didn’t know this. Fascinating!
It would be worth investigating the impact of insufficient water reservoirs on mass flooding in Pakistan. For example, India does not get regularly flooded to the same extent despite having more rivers than Pakistan and all of them originating from a high gradient somewhere in Karakoram or the Himalayas like Pakistan. There are floods in India almost every season like Pakistan but never to the extent of 1/3 of the country under water. I doubt even 1/10th. The duration of the floods is also not as long as Pakistan where it can often last several months since the only egress available is the Arabian sea. The current floods are the second mass incident in recent years. The 2010 floods affected more than 20 million people. Are there geographic/topological reasons that prevent mass, long-running floods in India? Or merely a lack of investment in a reservoir network.
You’re the 2nd to ask. I don’t know yet but would love to!
This is fascinating, thanks! I never knew that Pakistan had so many glaciers!
Well, if this goes on (and it will), the number of glaciers in Pakistan will soon be lower.
True enough.
7000! More than any other country that is not in a polar area! More than China or India, who have the Himalayas and Tibet! Mindblowing... I have read that, although I have looked for a list of glaciers per country and haven't found it. So i'd take that fact with a grain of salt. What is true though is that Pakistan has an astounding number of glaciers.
There are also glaciers that feed water into the rivers in China. Given the heatwave there, why didn’t the increased water from melting glaciers mitigate China’s drought?
I don't know yet. I'd love to!
Looking at the Map it seems the vast Tibetan plateau (incredible mountainous, but mostly above 4000m elevation) is having ranges and valleys that are running from east to west.
The whole land is very dry and the water that is coming from the glaciers is running to Ladakh and then Pakistan. The plateau ends in the north in another high mountain range (border to China more or less) and that part of China (Xinjiang and Qinghai) are mostly big, dry deserts where a few rivers run to but do not pass through.