claim: The connection between the vanishing Arctic ice and extreme summer weather in the northern hemisphere is probable, according to scientists, but not yet as certain as the winter link.
evidence: While the full implications of elevated CO2 on marine ecosystems are still being documented, there is a substantial body of research showing that a combination of ocean acidification and elevated ocean temperature, driven mainly by CO2 and other greenhouse gas emissions, have a compounded effect on marine life and the ocean environment.