Glass sphere

Every chart drawn in this format, newest first. How it reads: Methodology.

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  Texas Reservoirs, 1950–2026

  Texas's water-supply reservoirs as a glass sphere, month by month from the drought of the 1950s to today.

  Updated 25 September 2026
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  US Natural Gas in Storage, 2010–2026

  The natural gas stored underground in the Lower 48 states as a glass sphere, filling every summer and drawn down every winter, week by week since 2010.

  Updated 18 September 2026
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  The Strategic Petroleum Reserve, 1977–2026

  The US Strategic Petroleum Reserve as a glass sphere, filling from its first barrels in 1977 to its 2010 high and draining since, week by week.

  Updated 18 September 2026
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  Lake Mead's Water Level, 1935–2026

  Lake Mead as a glass sphere filling and draining month by month since 1935, with a dashed line at 1,035 feet, below which most of Hoover Dam's turbines cannot run.

  Updated 24 September 2026