Source: Barcroft Media
They look not unlike a series of modern art portraits, but these mesmerising patterns are actually satellite images of some of the planet's most spectacular river deltas.
Seen from space, rivers including the Nile, the Ganges and the Yangtze, make paths resembling branching blood vessels, crossing entire continents until they reach the sea,
"The photos show a variety of forms associated with river deltas," said Dr. Helene Burningham, 39, a Lecturer in Physical Geography at University College London
"Deltas are accumulations of sediment at river mouths.
"The term 'delta' is derived from the greek letter 'delta', which in its capital form is triangular, a common shape of river deltas, such as the Nile."
From so far away it's impossible imagine the 500 million people who live around the banks, or of the natural disasters that can take place.
"Deltas offer a wide range of environments, including valuable wetlands that provide significant ecosystems," said Helene,
"The Ganges-Brahmaputra delta covers a large area of southern Bangladesh and east India, and is one of the most densely populated areas in the world."
"It is an excellent example of the importance of deltas in providing many resources for human populations, including fertile land for agriculture and access to fishing."
But there can be dangers of living around deltas.
"Deltas are inherently low-lying and can be easily eroded. They are vulnerable to sea level rise, which may result in increased flooding."
"Deposition of more sediment also adds weight to the delta, which can often result in sinking of the delta landform, thereby increasing the likelihood of flooding."
There are many causes of change to delta systems over time, and they often occur in cycles.
"Causes are both natural and human-induced," said Helene
"Sea level rise associated with global warming is probably the most important impact of global warming on river deltas."