There Are Rivers in the Sky by Elif Shafak

BookBar says: Elif Shafak's latest is set between two continents over two thousand years: the rich and whimsical stories of a Victorian child, fascinated by stories of Ancient Mesopotamia; a teenage girl who journeys from contemporary Turkey to Iraq; and heartbroken hydrologist living on the River Thames.
 
'A storm is approaching Nineveh, the sky swollen with impending rain. One of the clouds approaching the world's largest and wealthiest city, built on the banks of the river Tigris, is bigger and darker than the others-and more impatient. It floats suspended above a majestic building adorned with marble columns, pillared porticos and monumental statues. This is the North Palace, where the king resides in all his might and glory. The cloud casts a shadowover the imperial residence. For unlike humans, water has no regard for social status or royal titles. Dangling from the edge of the cloud is a single drop of rain - no bigger than a bean and lighter than a chickpea. For a while it quivers precariously - small, spherical and scared. Howfrightening it is to observe the earth open down below like a lonely lotus flower. Remember that raindrop, inconsequential though it may be compared to the magnitude of the universe. Inside, it holds a miniature world, a story of its own...'