I think it's global warming brought on by the human race using too many fossil fuels. The world has been a very different place since we became energy dependant. The Untied States alone uses more energy than any other, but you would be silly to not think, this has complications.
There is no question that human beings are responsible for sea level rises. This is agreed on by all of science. This isn't a debate among scientists. This is only a debate among bible-thumping lunatics and people who are actually rational. So yes, we are, for certain, responsible for sea level rises.
If we are not entirely responsible for sea level rise, we definitely have played a massive part in it. We create an immense amount of greenhouse gases every day. These gases are trapped in our atmosphere and cause the temperature to rise, this rising tempature causes glaciers to melt into the sea, causing them to rise.
No, I do not think that humans are responsible for sea level rise, because we are just living our lives just like we always have. The rise is sea level comes and goes. It is a weather event, not climate, that the sea levels rise and fall. Humans are not to blame.
I do not believe humans are 100% responsible for sea level rise. I believe the planet naturally cycles through cold periods and warm periods. I think we are currently moving out of a cold period and into a warm period. At the same time, I believe we have implemented global warming that goes beyond the norms. I think we have impacted the environment, but not to the extremes some claim.