# Stop Evaporation — stopevaporation.com

> A neutral, cited knowledge base on water evaporation from open water bodies
> (reservoirs, ponds, lakes, industrial basins): the physics, how to calculate
> it, its impacts, and every practical method to reduce it. Operated in
> association with AWTT (awtti.com); product figures attributed to AWTT are the
> manufacturer's own, and competing/natural methods are covered on equal, cited
> terms.

## Core knowledge (pillars)

- [What Is Evaporation?](https://www.stopevaporation.com/what-is-evaporation): The physics (vapour-pressure deficit), the six driving factors, why depth doesn't change the rate, night-time loss, measurement, and impacts.
- [How to Calculate Evaporation](https://www.stopevaporation.com/how-to-calculate-evaporation): Pan, energy-budget, mass-transfer, Penman-Monteith (FAO-56), Priestley-Taylor and Hargreaves-Samani methods, with accuracy ranges (±10–20%) and an illustrative estimator.
- [Methods to Reduce Evaporation](https://www.stopevaporation.com/methods-to-reduce-evaporation): Every method class compared neutrally — natural, chemical monolayers, shade balls, suspended covers, modular floating covers, geomembranes, floating solar, and storage management — with a sourced comparison table and decision framework.
- [Evidence & Case Studies](https://www.stopevaporation.com/evidence): Peer-reviewed and field findings (Mady 2021, Lehmann 2019, Yao 2021, Craig 2005, Harbeck 1962), why performance varies, and documented outcomes incl. the 2017 U.S. DOE Sustainability Award (Savannah River Site).

## Methods (cluster pages)

- [Modular Floating Covers](https://www.stopevaporation.com/methods/floating-modular-covers): Tiles, balls and hybrid panels; ~65–80% field (Mady 2021) up to 95–98% at near-full coverage; where AWTT's Hexprotect AQUA and Rhombo Hexoshield appear as examples.
- [Geomembrane Covers](https://www.stopevaporation.com/methods/geomembrane-covers): Continuous floating covers; ~95%+ seal (Yao 2021); access/gas trade-offs.
- [Shade Balls](https://www.stopevaporation.com/methods/shade-balls): HDPE spheres; ~66–75% field.
- [Suspended Covers](https://www.stopevaporation.com/methods/suspended-covers): ~85%; surface stays clear.
- [Floating Solar (FPV)](https://www.stopevaporation.com/methods/floating-solar): Evaporation reduction plus power generation.
- [Chemical Monolayers](https://www.stopevaporation.com/methods/chemical-monolayers): ~20–40% (Craig 2005); wind-sensitive.
- [Windbreaks](https://www.stopevaporation.com/methods/windbreaks): ~5–20% in small systems.
- [Duckweed (Lemna)](https://www.stopevaporation.com/methods/duckweed): Floating mat; ~27% living / ~23.5% dead (Soltani 2020); oxygen/ecology trade-offs.
- [Floating Azolla](https://www.stopevaporation.com/methods/azolla): Low-profile floating fern; ~26% alone, up to ~46% with a monolayer (Wetlands 2020); nitrogen-fixing.
- [Palm Fronds & Organic Covers](https://www.stopevaporation.com/methods/palm-fronds): Inert floating debris; 47–76% by coverage (Al-Hassoun 2011); decomposes, needs replenishment.
- [Natural Shading (Riparian)](https://www.stopevaporation.com/methods/natural-shading): Trees/canopy shade for small ponds and channels; effect by mechanism (water temperature), open-water % not reliably quantified.
- [Storage & Reservoir Management](https://www.stopevaporation.com/methods/storage-management): Deepening, compartmentalisation, underground storage.

## Research & technology

- [Research Library](https://www.stopevaporation.com/research): A cited, continually-updated index of peer-reviewed studies, reviews, datasets and standards on evaporation suppression — filterable by method, study type and year. New publications are auto-ingested from OpenAlex (deterministically gated, copyright-safe paraphrases) and labelled "pending review" until checked. RSS: https://www.stopevaporation.com/research/rss.xml
- [Technology Landscape](https://www.stopevaporation.com/technology): A neutral, alphabetical scan of real vendors and technologies across every reduction method class (floating-modular, geomembrane, shade balls, floating solar, chemical monolayers). AWTT is the site sponsor and appears here on equal terms with competitors. New products/technologies are auto-discovered via web search (deterministically gated, grounded in real citations, sponsor-excluded) and labelled "pending review" until checked.

## Calculation deep-dives (cluster pages)

- [Penman-Monteith (FAO-56)](https://www.stopevaporation.com/calculate/penman-monteith) · [Priestley-Taylor](https://www.stopevaporation.com/calculate/priestley-taylor) · [Mass-transfer](https://www.stopevaporation.com/calculate/mass-transfer) · [Energy budget](https://www.stopevaporation.com/calculate/energy-budget) · [Pan evaporation](https://www.stopevaporation.com/calculate/pan-evaporation) · [Hargreaves-Samani](https://www.stopevaporation.com/calculate/hargreaves-samani): Each with the equation, variables, inputs, a worked example and accuracy notes.

## Guides by climate

- [Guides hub](https://www.stopevaporation.com/guides): Climate-specific guidance — arid/desert, semi-arid, Mediterranean, tropical/humid, temperate and high-altitude reservoirs — matching the dominant evaporation drivers to the best-suited methods.
- [Cost of evaporation](https://www.stopevaporation.com/cost-of-evaporation): An illustrative water-savings and payback estimator (no vendor pricing).

## Reference

- [Glossary](https://www.stopevaporation.com/glossary): Key terms as structured definitions.
- [Resources](https://www.stopevaporation.com/resources): Citation library (FAO-56, USGS, etc.) and authoritative tools.
- [About & Disclosure](https://www.stopevaporation.com/about): Mission, neutrality standards, and the AWTT relationship.
- [Knowledge Hub (blog)](https://www.stopevaporation.com/blog): Evergreen explainers and current developments.

## Tools

- AWTT evaporation calculator (authoritative, multi-method, real-weather): https://www.awtti.com/calculators/evaporation/
- Research RSS feed (latest publications): https://www.stopevaporation.com/research/rss.xml