Drive less, drive less gas-guzzling cars, plant trees, recycle your plastic, glass, and paper, buy 'organic-based' clothes, turn your thermostats down/up depending on temps outside, support nuclear/wind/solar/geothermal energies.
Nothing matters, or solves the ultimate cause of the problem except one: control human overpopulation and growth!!
Of course, you will NOT hear ANY politician, religious, or even many environmental leaders suggest such a solution.
Doesn't matter: we'll hit the 'typical' 3 million year 'lifespan' for a species and then we'll disappear. No, it won't be Jesus coming to rapture us per the Christian superstition, it won't be Jesus returning, killing/converting all to Islam (or killing the rest, or whatever) per the Islam superstition, and it won't be the end as per the Mayan Calendar.
We'll simply, quietly EXPIRE.
Save the EARTH? The Earth will be here LONG after we're gone.