Dear Prime Minister Harper,

We are concerned that the major issue about the bitumen sands project and the pipelines to carry the bitumen or processed oil has not been understood--the dangerous consequences of the vast increase in greenhouse gas emissions ensuing, on top of the excessive carbon dioxide already in the atmosphere. We have already exceeded 350 ppm, the limit many leading climate scientists tell us should not be passed to avoid runaway climate change.

Refining the bitumen in Alberta will not reduce global emissions.

JustEarth members wrote two letters to Prime Minister Stephen Harper and President Barack Obama about the tar sands and Keystone XL pipeline.

We encourage you to write your own letters to Prime Minister Harper and/or President Obama.

The letters can be seen here:

• To Prime Minister Stephen Harper
• To President Barack Obama

It's time to recognize that climate change is an EMERGENCY and get serious about addressing it! Our lavish use of fossil fuels is risking runaway climate change, with feedback effects that can lead to mass extinctions (50-70% of species). There have been mass extinctions on this planet before from which bio-diversity recovered -- in some 50 million years.

There are reasons--both of short-term economic advantage and long-term survival--for dealing seriously with climate change.

The forest fires in B.C. have already cost lives and resources. People in the interior are concerned about insurance rates and even the possibility of not being able to get any insurance, yet extreme weather events are expected to increase in frequency and severity.