Mr Gore ascribed Hurricane Katrina to global warming, but there was "insufficient evidence to show that"

William:

3. There is insufficient evidence to establish clearly that particular one-off weather events, such as Hurricane Katrina, are attributable to climate change. However, the IPCC concludes that it is likely that there has been an increase in intense tropical cyclone activity in some regions and more likely than not that humans have contributed to this

 

I agree with all that.