The melting of polar ice due to climate change will open global shipping routes through the Arctic in summer by mid-century, according to experts. More ships in the remote area means greater pollution impacts on the marine ecosystem. What will these impacts look like? In a first commissioning experiment at MAX IV’s SoftiMAX beamline, Swedish researchers analysed the cloud-forming abilities of particle exhaust from ships using low-sulphate fuels as well as high-sulphate fuels conditioned with wet scrubbers. Their findings indicate the fuel types produce different, but unintended effects on particle emissions and therefore, our atmosphere.