グリーンクレーテニスコートは10年後にはカーボンネガティブになる（Green clay tennis courts become carbon negative after 10 years）

2026-03-27 ワシントン大学（UW)

＜関連情報＞

• https://www.washington.edu/news/2026/03/27/march-research-highlights-nautilus-habitat-eco-friendly-tennis-courts-more/
• https://www.sciencedirect.com/science/article/abs/pii/S0883292726000612

アメリカのグリーンクレーテニスコートにおける風化促進による二酸化炭素除去 Carbon dioxide removal by enhanced weathering on American green clay tennis courts

Frank J. Pavia, Jonathan E. Lambert
Applied Geochemistry  Available online: 18 February 2026
DOI:https://doi.org/10.1016/j.apgeochem.2026.106737

Highlights

• Green clay tennis courts are a sink for atmospheric CO₂ through weathering reactions with their metabasalt feedstock.
• We model CO₂ uptake on green clay tennis courts, taking into account location, grain size, and emissions during construction.
• Green clay courts in the U.S. sequester >25,000 tonnes of CO₂ per year and 80% of green clay courts generate net negative emissions within 10 years.
• Life-cycle analysis reveals that U.S. green clay tennis courts have substantially lower emissions during construction than hard courts.
• Replacing existing hard courts with green clay courts can generate quantifiable, additional CO₂ drawdown.

Abstract

40,000 tennis courts in the United States are constructed and maintained by spreading basalt feedstock similar to that used for carbon dioxide removal via enhanced rock weathering. Silicate weathering therefore readily occurs on these courts, yet the carbon sequestration associated with this weathering has never been quantified. We have built a model that quantifies net CO₂ sequestration during the lifetime of green clay tennis courts. We calculate gross CO₂ sequestration rates associated with silicate weathering and conduct a lifecycle analysis for emissions during court construction. This allows us to determine net sequestration rates at each court as well as assess the factors that lead to maximal CO₂ sequestration at different sites. We find that transportation distance from the singular Blue Ridge metabasalt processing site is the primary source of emissions for most tennis courts. Taking all factors into account, green clay tennis courts sequester over 25,000 tonnes of CO₂ per year and the median court becomes net CO₂ negative in 3.5 years. Our emissions analysis also shows that green clay tennis court construction emits 1.6-3 times less carbon dioxide than hard courts do over their entire life cycle. We conclude by discussing the potential for changes in feedstock characteristics and green clay tennis court maintenance practices that can further reduce their carbon footprint and the pathway towards producing verifiable carbon removals on green clay tennis courts.