This post was contributed by guest blogger Sebastian Blanco, editor in chief of AutoblogGreen.

No one can tell you what kind of car to buy, but here's a case for making your next vehicle one that uses the least possible amount of fossil fuel.

It was reported recently that the overall cost of climate change — the various damages from things like floods, drought and other connected issues — could top $8 trillion by 2030. The number comes from the consultancy group Mercer and the World Bank's International Finance Corporation, which released a study recently that found that climate change — wildly misunderstood and able to create great risks — could add up to 10 percent to investors' portfolio risk in the next two decades. The best solution, the authors say, is to try and add resilience of future portfolios by investing in "infrastructure, real estate, private equity, agriculture, timberland and sustainable assets." You can download the full report, the highlights or the executive summary (all PDF links).

On top of the investor losses, we may be spending a lot of money to fix the problems that climate change brings. On-the-ground damage from climage change could damage roads, bridges, railroads and other infrastructure items. An estimated 60,000 miles of highways could be damaged, for example.

On top of this, the report found:

  • The cost of impacts on the physical environment, health and food security could exceed $4 trillion.
  • Climate change-related policy changes could increase the cost of carbon emissions by as much as $8 trillion.
The report adds: "Clean energy today accounts for a very small portion of asset allocation — less than 1 percent of portfolios for most large pension funds. Even one additional percentage point in allocation would represent a doubling of monies made available to low-carbon assets."

Not all of us can make a statement with our investments. Since I write about green cars so often, it seems clear to me that "green" vehicles come into the picture in a big way. These clean(er) rides most certainly can't reverse climate change by themselves, but even so, they move us into the right direction because they offer us something our current situation doesn't: choice.

Whether it's putting renewable energy from the sun or wind into your plug-in car, burning natural gas in a Honda Civic GX (the greenest vehicle of 2011) or making biodiesel for your pickup truck, putting your money down on a vehicle that's not powered (solely, at least) by gasoline gives the auto industry one more reason to offer us even more choices later. That oil prices can fluctuate like mad while utility rates often stay pretty stable is just icing on your new car cake. And it sure beats doing nothing.

Jim Motavalli ( @jmotavalli ) writes about cars, technology and the environmental world to anyone curious enough to ask.

The high cost of climate change, and what you can do about it
Repairing the damage we've done could get pricey, especially since it's predicted to cost us $8 trillion by 2030.