Nature: Ion-induced nucleation of pure biogenic particlesCLOUD has done lots of measurements of the processes that are needed to create clouds which, as many kids have noticed, usually cool down the weather.
Science: New particle formation in the free troposphere: A question of chemistry and timing
AP (a popular/politicized distortion): New Cloud Formation Discovery May Lessen Warming Forecast
The experiment has been taking place at CERN because the cosmic rays (emulated by the CERN's sources of beams) are important for the creation of the cloud (condensation) nuclei. Even in the new papers, cosmic rays are found to increase the nucleation rate by 1-2 orders of magnitude. Recall that the Sun's activity may influence the cosmic ray flux, and therefore its variations may be responsible for "climate change".