The Journey of a Drop Along a Flying River. Totica: From the Amazon to Tota

Tota: Mirror of the Cosmos.

On Lake Tota, at more than 9,843 feet (3,000 m), the swallows fly low: they know that rain is coming. Two perch and look at a river that flows not on the ground, but in the sky: a river of clouds that arouses the curiosity of the wren and the rail.

Lake Tota is the largest high Andean wetland in Colombia and a refuge for 170 bird species. Home to 10 endemic species in the country and 2 in the Altiplano Cundiboyacense: the Apolinar's wren (Cistothorus apolinari) and the rail (Rallus semiplumbeus).

Flying rivers are vapor currents that travel through the atmosphere and can carry more water than the world's largest river, the Amazon. In South America, they travel up to 1,864 miles (3,000 km), generating much of the rainfall that sustains ecosystems and crops.

Water has always been in flux. The birds know it because of Totica, a thousand-year-old drop that is almost as old as the planet. She's been around for over 4 billion years, swimming in the ocean with marine reptiles and sleeping on glacial peaks.

Something that Tota's birds have always found extraordinary is that we are drinking the same water as the dinosaurs. Although water is always moving, Totica explains that no single drop enters or leaves the Earth: the same drops travel around the planet, over and over again.

Totica, has always enjoyed living on the Cundiboyacense plateau, whatever the geological era. The traveling droplet always ends up back there, propelled by the easterly winds: its journey usually begins in the Atlantic, where the sun turns it into vapor and sends it up to the clouds.

The tropical Atlantic is the main source of moisture for the flying rivers of South America. Evaporation and condensation fuel these air currents, which, driven by the trade winds, travel from the Atlantic Ocean to the Amazon.

Flying rivers are also topped up with moisture from forest evapotranspiration, a process known as moisture recycling. The estimated 400 billion trees in the Amazon release 20 billion tons of water into the air every day.

The Amazon rainforest emits microscopic aerosols, known as volatile organic compounds (VOCs), which act as cloud condensation nuclei: the particles on which water vapor in the atmosphere condenses to form raindrops.

But the dance is not endless, even in the tropics, and when the flying river meets the natural wall formed by the Andes, the drops collide with each other and begin to fall: sometimes as drizzle, sometimes as a storm, filling up Andean rivers and lakes.

The downpour on Lake Tota has become torrential, so the high mountain birds have sought shelter while the swallows have begun to fly through the rain, longing to hear the news that Totica will bring with her from her latest journey.

The Lake Tota basin, which contains ~14% of Colombia's fresh surface water, receives most of its rainfall between April and July, while the driest months are December and January. The El Niño phenomenon reduces rainfall in the warm phase and increases it in the cold phase (La Niña).

In 20 years, the Amazon has lost 134 million acres (54 million ha), disrupting the water cycle and the flying rivers that bring rain to the Andes. Stopping deforestation is possible: every tree we care for helps life and rainfall to continue.