Are you a Sustainability Guru?

A fun and educational game about green topics. How much do you really know?

Level 1

Prior to the industrial revolution the highest recorded concentration of CO2 in the atmosphere over the last several hundred thousand years is around 300 parts per million (ppm). What is the concentration today?

Pick the best answer

  1. 280 ppm
  2. 300 ppm
  3. 380 ppm
  4. 450 ppm
We will be continually adding more questions so make sure to play again!
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More Information

The Game

Each correct answer increases your score and gets you closer to the next level.
Each incorrect answer decreases your score.
The maximum possible score is 50 and is the Guru level.
You can answer as many questions as you like. Eventually questions will repeat after we run out of new ones for you.
If you are a member, and logged in, your highest level is recorded on your profile.
Members get one of 6 levels: Newbie, Trendy, Devotee, Scientist, Apostle, or Guru.
Guru Rankings
If you Log in your level will be saved.
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