Kidney failure, mostly. If your cats (or someone else's) brush against the lilies and then groom the pollen off their fur, it can cause their kidneys to fail, which is expensive to fix, painful, and potentially fatal. Even tiny amounts will do it.
Hydroelectric dams are great in theory, but are awful for the ecosystem around them, especially downstream. Everywhere they've been put in, you'll find environmentalists, and I mean actual scientists, wanting them back out. They decimate the river ecosystem in both directions, sometimes for miles. They also cause problems where the river is supposed to meet the sea- vital brackish water habitat is lost to saltwater as the pressure of the onrushing fresh water recedes. Several major rivers in the US barely make it to the sea at all, at this point.
And global CO2 emissions are at 2.4 million pounds per second. Constantly. Every second of every year. Volcanoes don't put out anything near that.
Decent bets at this point are in places to get clean water, in food plants that can withstand temperature swings in either direction and bad weather events, and in making your house as resistant as possible to things like tornadoes and (when even remotely relevant) blizzards.
Also, in policy changes. We have the technology at this point to completely negate carbon emissions with filters. It would be very expensive, but not prohibitively so with the right taxes in the right places. Other ideas along the lines of as much greenery as possible and reducing output in the first place are also excellent. Some combination of them and other ideas is probably the best option, but none of it will help in any way if it isn't done. It is entirely possible, with technology and resources that we already have, to get the amount of excess carbon (read: carbon that assorted plant life can't absorb) down to 0.
However, even if humans started emitting 0 excess carbon tomorrow, there would still be changes. An overall increase in global temperature changes- well, you can read up on it for yourself, but expect worsening flooding and severe weather.
(and please note that your graph there lists 'now' as 2011, and that, in every graph from a reputable source, i.e. one that labels both axis, temperature changes are much faster now than in prior times. Also that prior temperature swings caused famine, severe weather events, and overall chaos and death.)
Or, ya know. We could go with the idea that nearly every reputable environmental scientist in the world is part of a global conspiracy to... what, to make it so that we release less CO2?
Look up "is manmade climate change real". You will see an overwhelming "yes", so I guess Google is also part of that conspiracy, too. And every other search engine you can think of. And pretty much every relevant scientist you can find to ask.
I'm not sure how readable all that is, there's a thunderstorm keeping me awake a couple hours past where I should be asleep, but the takeaway is that manmade climate change is real. If someone tells you otherwise, they are probably either misinformed, or they're trying to sell you on something. I guess that's not too surprising, since major fossil fuel companies have been hiding for a few decades now that what they're doing is, and was already, harmful in the long run.
We are at a critical turning point for environmental regulation. There need to be big changes made, and soon, to stop things from getting even worse than they're already going to be. People are going to die, and already are- look at the flooding and famines already happening and getting worse. Look at everyone dying in storms.