NASA has posted a series of satellite photos documenting the expansion of the Athabasca tar sands. The Athabasca pits cover over 54,000 square miles in Alberta with an estimated reserve of 1.75 trillion barrels of oil - good enough for third in the world behind Saudi Arabia (1) and Venezuela (2).

Production increases noticeably from the mid-1980s to present day:

Visible in the pictures are the tailing ponds holding contaminated water and material from the extraction process, along with surface stripping.

So, in light of the near-certain death of the Keystone XL pipeline, will Canada's tar sand production continue to grow in the coming years? Or do environmental stewardship and carbon consciousness counter the global demand for cheap energy?

All photos courtesy of the NASA/Goddard Space Flight Center.

Update: A few of us have been discussing these pictures on Twitter. Apparently NASA's Earth Observatory site has satellite images for every year between 1984 and 2011, along with a scale to put the distances in perspective. Check them out to see the year-to-year progression. Thanks, Matthew.