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About Us

The Cloud Appreciation Society

Our society was launched in 2005 by Gavin Pretor-Pinney, Member 0001, to bring together people who love the sky.

We have members in 120 countries around the world, all united in the belief that clouds are the most dynamic, evocative and poetic aspect of nature. Read our manifesto to see what we stand for.

Gavin Pretor-Pinney (Member 0001)

Our Organisation

We decided from an early stage not to make the Cloud Appreciation Society a non-profit. We believe an organisation is most sustainable when it works as a business. Otherwise, it can become so preoccupied with applying for grants and raising donations just to survive that it loses sight of it original aim. In our case, this aim is to promote a greater understanding and appreciation of the sky and our atmosphere as a whole. The important thing, in our opinion, is what a company does with its profits…

During 2019, we’re helping a village in Guatemala build a greenhouse that is watered by clouds

Throughout this year, we are donating 5% of all the membership fees we gather to the Canadian non-profit FogQuest to support a project in the highlands of Guatemala. This follows our support for them in 2018 to help villagers in Tojquia, Guatemala use the simple but effective technology of ‘fog harvesting’ to turn the regions abundant mountain fog into fresh drinking water. The 2019 project that the Cloud Appreciation Society is supporting involves building a large greenhouse next to the village school that will be irrigated with water collected from the fog.

Based in British Colombia, Canada, FogQuest is run by retired cloud physicist Dr Bob Schemenauer. Bob’s team is a world leader in installing ‘fog harvesting systems’, and has been working with the highland communities around Tojquia, Guatemala since 2006.

Gathering fresh water from fog is nothing new. Plants have been doing it for millions of years, using fine structures on their leaves to snag the minuscule fog droplets and gather them into larger drops that they can drink. Fine mesh structures in ‘fog collector’ nets do exactly that same thing. In the right climate, and positioned so that upland fog blows through them, these nets can collect sizeable quantities of fresh water which would never have fallen as rain.

The village of Tojquia is at an elevation of 3400 m (11,000 feet) in the Western Highlands of Guatemala. In the winter it is relatively cold, windy, foggy, but with little or no precipitation. FogQuest has started discussions with the community regarding erecting a moderately large greenhouse near or attached to the existing school. This will involve erecting two large ‘fog collectors’ to provide water for the greenhouse.

35 large nets have already been installed through FogQuest by the communities of Tojquia, who live at 3300m above sea level. In total, these are collecting an average 6,300 litres (1,650 gallons) of water per day through the cold and very dry winter months. The region is not suitable for wells, and so before their installation water had to be carried by foot over considerable distances usually by the women and children.

For this greenhouse project, the fog water would be stored in large plastic tanks to ensure a constant supply throughout the year. FogQuest plan to partner with a Guatemalan university to determine what specific crops might be grown in the greenhouse to augment the village food supply, especially in the winter. These would have to be culturally appropriate, accepted by the community, adopted by the women of the community, able to be grown successfully, be clean and healthy, and beneficial to the community. Assuming everything progresses well, the field work for installing the greenhouse and fog collectors will most likely be in the autumn (fall) of 2019.

FogQuest is a small, all-volunteer charity that spends at least 90% of donations directly on fog-water projects in developing countries. The money we’re giving them in 2019 will buy the greenhouse equipment, pipes and fog-collecting nets for this project. Each net collects an average of 180 litres of fresh drinking water per day through the dry and foggy winter months.

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The school house in Tojquia, Guatemala. Through 2019 we aim to fund all the equipment needed for the villagers to build a greenhouse watered by fog collectors.
The technology couldn't be simpler: a net, a frame and some pipework. In the foggy winter months, each net gathers 180 litres (48 gallons) of fresh water a day.
There is plenty of rain in the summer, but during the cold and foggy winter months the region is very dry. It is no good for wells, so the villagers – usually the women and children – used to have to walk long distances to collect water.
Fog droplets gather on the mesh and dribble down into the collector at the base of the nets to gather as fresh drinking water. Simple as that.