The Guardian reports: Climate change has already left its mark “on all continents and across the oceans”, damaging food crops, spreading disease, and melting glaciers, according to the leaked text of a blockbuster UN climate science report due out on Monday.

Government officials and scientists are gathered in Yokohama this week to wrangle over every line of a summary of the report before the final wording is released on Monday – the first update in seven years.

Nearly 500 people must sign off on the exact wording of the summary, including the 66 expert authors, 271 officials from 115 countries, and 57 observers.

But governments have already signed off on the critical finding that climate change is already having an effect, and that even a small amount of warming in the future could lead to “abrupt and irreversible changes”, according to documents seen by the Guardian. [Continue reading…]