Climate Change
A dashboard of the physical basis, observed impacts, scenarios, and the near-term solutions space. Last data refresh: NOAA Mauna Loa, IPCC AR6, Berkeley Earth.
The Keeling Curve, extended
Atmospheric CO₂ measured continuously at Mauna Loa, Hawaii, since 1958 by Charles David Keeling — the first instrumental confirmation that humans were altering global atmospheric chemistry.
Sources: NOAA GML; Lüthi et al. 2008 EPICA Dome C ice core.
How a Greenhouse Works
Sunlight (shortwave) passes through the atmosphere. Earth's surface absorbs and re-radiates it as longwave (infrared). Greenhouse gases — CO₂, CH₄, H₂O, N₂O — absorb longwave and re-emit it back downward, warming the surface.
Without this effect, Earth's average temperature would be -18°C. With it: +14°C. The question is not whether greenhouse gases warm the planet — they do — but how much warming current emissions add.
The Five SSPs
The IPCC's Shared Socioeconomic Pathways describe possible futures of population, economy, and emissions. Each is paired with a Representative Concentration Pathway (RCP) — radiative forcing in W/m².
Median 2081–2100 warming relative to 1850–1900 (IPCC AR6 WG1).
Already Here
Ice
Arctic sea ice minimum extent declining 13% per decade. Greenland Ice Sheet has lost ~280 Gt/yr since 2002. Antarctica losing ~150 Gt/yr. The Thwaites Glacier ("Doomsday") buttresses 1.2m of potential sea level rise.
Heat
Pacific Northwest 2021 dome reached 49.6°C in Lytton, BC — a record by 4.6°C. Made 150x more likely by warming. Europe 2003 heatwave killed ~70,000.
Coral
Fifth global mass bleaching declared April 2024 by NOAA. The Great Barrier Reef has bleached in 2016, 17, 20, 22, 24. 50% of reefs lost since 1950.
Permafrost
Yedoma soils of Siberia store 1,500 Gt carbon — twice the atmosphere. Thawing releases CO₂ and CH₄, a feedback. Northern hemisphere permafrost area shrinking ~17% per decade.
James Hansen, June 23, 1988
"Global warming has reached a level such that we can ascribe with a high degree of confidence a cause and effect relationship between the greenhouse effect and observed warming."
NASA scientist Hansen testifying to the US Senate during a record-breaking summer heatwave. The first major public statement that climate change had been detected. He was 47, working at the Goddard Institute for Space Studies, and almost no one believed him. He was right.
The Compounding Storm
Idai struck Beira on March 14–15, 2019: 175 km/h winds, then four days of rain. ~1,300 dead across Mozambique, Zimbabwe, Malawi. 90% of Beira destroyed. Six weeks later Cyclone Kenneth hit further north — the first time on record two intense tropical cyclones struck Mozambique in a single season. Warmer Indian Ocean, wetter air, more precipitation per storm.
Decarbonization Levers
Project Drawdown; IEA Net Zero Roadmap 2023; IPCC AR6 WG3.
Kurzgesagt — Can YOU Fix Climate Change?
An animated explainer of personal vs systemic action, written with Hannah Ritchie of Our World in Data. 18 million views, exemplary data viz on what actually moves emissions curves.
The Working Climatologists
- Syukuro Manabe — Princeton, 1967 first GCM showing CO₂ doubling = +2°C. Nobel 2021.
- Klaus Hasselmann — fingerprinted human signature in climate noise. Nobel 2021.
- Michael Mann — 1998 hockey-stick reconstruction of millennial temperature.
- Katharine Hayhoe — atmospheric scientist, climate communicator, evangelical Christian.
- Friederike Otto — World Weather Attribution, founder of attribution science.
- Charles David Keeling — began Mauna Loa CO₂ record in 1958, ran it until his death.
What 1.5° Looks Like
The Paris target is not a ceiling that prevents harm — at +1.5°C we lose 70–90% of warm-water coral reefs, 14% of Earth's population is exposed to severe heatwaves once per five years, sea level rises ~50 cm by 2100. It is the temperature beyond which every additional tenth of a degree compounds the damage.
"The greatest threat to our planet is the belief that someone else will save it." — Robert Swan, polar explorer