Warming across Germany in the last 3 decades can be explained by declining cloud and aerosol albedo and consequent rising solar radiation. Not CO2.

Another new study affirms clouds and aerosols play a key role in explaining trends in solar surface radiation (SSR), which is “essential for the global energy cycle driving the climate system.”

Over Germany, five independent observational datasets all agree that SSR increased by 4 W/m² per decade (~10 W/m²) from 1995-2020.

A 4 W/m² per decade increase in SSR easily explains recent warming. It especially explains warming far better than the alleged 20-times smaller clear-sky-only CO2 impact (0.2 W/m² per decade) over this span.

Image Source: Pfeifroth et al., 2026

Supporting this new research, a 2024 study (Wacker et al.) utilizing a German “testbed site” reports total and direct shortwave (SW) radiation forcing rose by 3.5 and 9.3 W/m² per decade, respectively, from 1996-2021.

Image Source: Wacker et al., 2024