What is the basic reason for the flood that happened in the Nepal & Chinese border?

 Two powerful landslides (energy equivalent to a 5.2 Richter scale ) happened within a 3-hour gap. When massive rocks roll down the mountain, they generate plenty of heat, melting the glaciers and causing massive floods. The floodwater was 130-160 ft high and flowed at 44 miles per hour.

The mean temperature has increased by 1.71C in Nepal recently, causing shorter monsoon seasons, more intense rainfall and shifting precipitation patterns, higher temperatures, and droughts. 80% of Nepal’s rainfall occurs between June and September. In parallel, loads of construction happens without proper infrastructure planning. Roadside landslides are increasing; dykes are built along river segments, attracting more people to settle in dangerous places along roads in floodplains, not because they are unaware of the physical danger but because of the economic opportunities such places bring

There are 3 major challenges in predicting these landslides and floods to avoid disaster.

1. The lack of continuous and reliable local precipitation data
2. The topography of the Himalayan range is extreme and complex to study.
3. The pattern between the monsoon rainfall and ENSO (El Nin˜o Southern Oscillation) is changing.

Dharan is one of the major trading cities in Nepal,, located below the Siwalik foothills at 400–500 m above sea level. This is where the British created the “ Gurkha Center”. This city is flanked by two larger rivers – the Sardu Khola to the west and Seuti Khola to the east – and is bisected by several smaller rivers crossing the city – the Khahare Khola and Turke Khola. All of the streams are subject to flash flooding. Urban runoff, encroachment of settlements on riverbanks and in river channels themselves, poorly maintained canalizations, upstream deforestation, and increasingly intense monsoon rains have together led to severe flash floods and landslides here, killing many residents instantly.

People living here rebuild their houses almost once a year because of flooding. So the people who live here are well aware of floods and landslides, but they can’t move out as the cost of living in “safe areas” is higher, which is not affordable for the marginalized community.

The priority of the local municipality is providing clean drinking water, education, and garbage disposal. Flood-related risk is the last priority. The local govt doesn’t have high-end technologies; they depend on basic tools like GIS, but old versions of the software, low-performing computers, and virtually no data useful for a GIS database. They also lack data on local rainfall and topography.

Nepal’s current development model is based on infrastructure development, not capacity building. Without capacity building, climate change models will remain inaccessible. The answer lies not in the tool (i.e., climate change scenarios and impact models) but in how the tool is used.

This requires good governance, resources, political willingness, and community participation, not just better data.

What is the oldest flood myth?

 The oldest recorded flood myth is the epic of Atra-Hasis, an Akkadian epic from 18th century BCE recorded on clay tablets.

The god Enlil wanted to wipe out all of humanity with a great flood. The god Enki however warned the wise priest Atra-Hasis, cleverly instructing him to build a large ark gathering animals and birds as well.

Description of Atra-Hasis boarding the ark and the onset of the great flood

Bringing ...whatever he had ...Whatever he had ...Pure animals he slaughtered, cattle ...Fat animals he killed. Sheep ...he choose and and brought on board. The birds flying in the heavens, the cattle and the ... of the cattle god, the creatures of the steppe,... he brought on board... he invited his people... to a feast... his family was brought on board. While one was eating an another was drinking, he went in and out; he could not sit, could not kneel, for his heart was broken, he was retching gall.

The outlook of the weather changed. Adad began to roar in the clouds. The god they heard, his clamor. He brought pitch to seal his door. By the time he had bolted his door, Adad was roaring in the clouds. The winds were furious as he set forth, He cut the mooring rope and released the boat.

... the storm... were yoked Anzu rent the sky with his talons,
He ... the land and broke its clamor like a pot... the flood came forth. Its power came upn the peoples like a battle,
one person did not see another, they could not recognize each other in the catastrophe. The deluge belowed like a bull, The wind resounded like a screaming eagle.
The darkness was dense, the sun was gone,... like flies.

• The epic of Atra-Hasis.

Everyone on the ark survived the flood and Atra-Hasis offered sacrifices for the gods. The other gods condemned Enlil’s flood and allowed humanity to repopulate the earth.

A variation of the story is also found in the epic of Ziusudra and later the flood myth in the epic of Gilgamesh would be inspired from this. Later flood myths of the region like the Biblical flood narrative is believed to be inspired from these.