global warming

Bilingual

Contrail Avoidance for the Climate
2 months ago
- Contrails contribute 1-2% of global warming, and most of this impact can be eliminated at near-zero cost.
- Aircraft cause warming through both greenhouse gas emissions and contrails, which form cirrus clouds that trap heat.
- Contrails cause as much warming each year as all CO2 emitted by flights from 1940 to 2018.
- Using weather forecasts, satellite imagery, and data, contrails can be modeled, detected, and avoided like turbulence or storms.
- Contrails.org is a non-profit working on contrail management systems to reduce aviation's climate impact.
A Spherical Cow Model of Global Warming (With Data and Code) - Bert Hubert's writings
2 months ago
- The article uses a simplified 'spherical cow' atmosphere model to explain global warming, focusing on CO₂ and water vapor.
- The Earth's surface temperature is determined by a balance between incoming solar radiation and outgoing longwave radiation, influenced by greenhouse gases.
- A key misconception addressed is that the 'CO₂ is saturated' theory is incorrect; adding more CO₂ still traps more heat by broadening absorption bands.
- Water vapor is a major greenhouse gas, but its concentration is dependent on temperature, creating a feedback loop that amplifies CO₂-induced warming.
- The model explains the role of the lapse rate (temperature decrease with altitude) in linking the temperature of the radiating atmosphere layer to the surface temperature.
- Doubling CO₂ concentration is predicted by simple and sophisticated models to cause several degrees of surface warming (e.g., 2–4°C or more).
- Venus serves as an extreme example of the greenhouse effect, with its thick CO₂ atmosphere causing a surface temperature of 737K.
- The article highlights unknowns, such as the water vapor continuum absorption spectrum and the complexity of modeling clouds and aerosols.
The 3-degree limit could be exceeded as early as 2050
3 months ago
- Global temperatures in 2023 and 2024 exceeded 1.5°C above pre-industrial levels, potentially surpassing the Paris Agreement limit permanently.
- The 2°C warming limit is at risk; acceleration could lead to 3°C by 2050 and up to 5°C by century's end without urgent action.
- Extreme weather events like droughts, heatwaves, wildfires, and heavy rainfall are increasing globally, causing significant damage and health risks.
- Heat and humidity in tropical regions may become unsurvivable outdoors before 2050, with ocean heatwaves and sea-level rise threatening coastal areas.
- Agriculture and water supply are destabilized by climate impacts, risking poverty and famine for millions, especially in the Global South.
- Immediate action is needed: reduce greenhouse gas emissions rapidly, switch to renewables, and develop carbon removal technologies.
- Germany and the EU must enhance efforts, as current measures fall short of 2030 and 2045 climate goals despite past emission reductions.
- Paths to a climate-neutral economy exist; decisive collective action can still avoid the worst scenarios, requiring political and societal commitment.

global warming

Contrail Avoidance for the Climate

A Spherical Cow Model of Global Warming (With Data and Code) - Bert Hubert's writings

The 3-degree limit could be exceeded as early as 2050