a new united natins report finds things are much worse than previously thought and wahes t mostsevere effects could be felt as early as 2040. for many of us, that is during our lifetime. the carbon emissions would need to be slashed 25% by 2030. meeting this goal would require a global commitment to phase out coal and replace it with renewable energy. joining me now is uc berkeley professor. first i wanted to ask you about the awful destruction caused by hurricane michael on the east coast. how much has climate change contribed to its furosity? >> it is still unleashing its damage, but the first scientific papers were already in on hu aicane floren few weeks ago on the carolinas. that storm was 50% warmer, 50% more damaging because of climate change and because of the extra heat in the ocean that we are seeing. 50% has caused a great deal of the surges, the damages. we can expect similar results from michael. >> let's a taut the u.n. report, as well. it is kind of connected. it is very comprehensive, the new report involving 91 ientists all over the world who analyze more than 6,000 s