Earth's clouds are shrinking, boosting global warming

Cloud changes, storms, and local weather

• Commenters highlight that reduced cloud cover, especially reflective low clouds, amplifies warming and can intensify hurricanes and cyclones, with major rainfall impacts even far inland and in mountainous regions (orographic rainfall).
• Some note local projections of increased rain and wonder how that squares with fewer “bright” reflective clouds; the distinction between cloud amount and cloud type/optical properties is emphasized.

What makes clouds dark and reflective

• Extended back-and-forth on why some clouds look dark:
  • Explanations offered: shadows from other clouds, viewing geometry relative to the sun, and especially cloud density blocking light.
  • Several note that dark storm clouds are white and highly reflective when seen from above (e.g., in satellite imagery), reinforcing their cooling role.

Power vs energy: units debate

• A long subthread dissects the phrasing “Earth gets over 170,000 terawatts of solar energy every day.”
• Points covered:
  • Watts are power, not energy; energy requires multiplying by time (e.g., watt-hours or joules).
  • “Watts per day” vs “watt-days” vs joules; many argue misuse of units undermines credibility, others say the intended comparison (huge solar input vs human use) is still clear.
  • Some tie the number back to the solar constant and Earth’s cross-sectional area.

Causes of shrinking clouds and human responsibility

• Several comments assume human-driven warming is altering circulation and thus cloud cover, framed as a powerful positive feedback.
• Others quote the article’s uncertainty: competing hypotheses include circulation changes vs pollution declines; one calls it a “complicated soup of processes.”
• A comparison to Neptune’s cloud changes linked to the solar cycle is raised; others counter that Earth’s multi-decade trend likely reflects different mechanisms.

Solutions, responsibility, and geoengineering

• Strong disagreement on “solutions”:
  • One camp insists technology plus political will (ending fossil subsidies, rapid decarbonization) could fix this quickly.
  • Others argue tech optimism is an excuse to avoid reduced consumption and lifestyle change; rich-world consumption is repeatedly labeled the primary driver.
• Cloud seeding and marine cloud brightening are discussed:
  • Potential to offset a large fraction of warming and be quickly reversible is noted.
  • Risks: regional rainfall redistribution, ecological side effects, and the danger of masking high CO₂ while becoming dependent on ongoing geoengineering.
  • Some think it may become a “hail-Mary” option if tipping points approach; others warn it’s too risky before deep emissions cuts.

Clouds, greenhouse effect, and water vapor

• Clarifications:
  • Clouds both reflect incoming shortwave radiation (cooling) and trap outgoing longwave radiation (warming); net effect depends on altitude, composition, and thickness.
  • Low, bright clouds generally cool; losing them enhances warming.
  • Water vapor is a greenhouse gas, but clouds are condensed water; warmer air can hold more vapor without forming clouds, so less cloud cover does not mean less greenhouse effect.

Risk, tipping points, and ecological timescales

• Some express fear of a runaway greenhouse and “Venus 2.0,” citing repeated discoveries of new feedbacks and albedo loss.
• Skeptics question climate predictions, pointing to weather-forecast uncertainty; others respond that:
  • Weather vs climate are different prediction problems.
  • Rapid glacier retreat and other visible changes show strong ongoing warming.
• A final thread addresses why warming is “bad” ecologically:
  • The core argument is speed: past warm periods unfolded over much longer timescales, giving ecosystems time to adapt.
  • Rapid change plus unknown new equilibria imply elevated risk of mass extinctions and large-scale disruption, not a simple shift to a “better for life” warmer Earth.