Form the "fertile crescent" and the sumerian civilization.
· over 1,730 miles long and characterized by annual flooding.
· headwaters are located in turkey, empties into the persian gulf.

which middle east geographic feature is being described?

The Euphrates river

Explanation:

Along with the Tigris, the Euphrates river helped form the Fertile Crescent and the Sumerian civilization.

It starts where the Karasu and Murat rivers merge in eastern Turkey and continues southeasterly for 2800 km (1740 mi) through Syria and Iraq until it merges with the Tigris river at Al-Qurnah. There, it becomes the Shatt al-Arab waterway and empties into the Persian Gulf.

places of higher salinity. there are parts of the ocean where hardly any rain falls but warm dry winds cause lots of evaporation. this evaporation removes water – when water vapour rises into the atmosphere, it leaves the salt behind, so the salinity of the seawater increases. this causes the seawater to become denser.