call to action? alternative solution?

After receiving feedbacks from previous project, I had thought over again on how to achieve call-to-action of my website, what I want the user to do after visiting the website? what makes them or encourage them to carry out the next step?

The purpose of my website is to educate user on how meat consumption or daily meat eating habit can cause global warming and how is it affected the environment, through interactivity. After user has gone through my website, the next step he/she is encouraged to do is to reduce the meat intake, so that every individual can help to reduce the rate of global warming. It's hard to make sure that every individual can be encouraged to reduce meat intake as different people has different perspective. But to engage them to start taking action can be done, which is I have thought of using social media where the website is targeted to 18-25 years old young adults who involve themselves in social media most of the time. Therefore, by integrating social media can be the method/platform to help encouraging them. Interaction between user and friends is the most common thing happens in Facebook. They usually checking out friends' updates, photos, relationship status, etc. Hence, I wanted to apply this scenario/situation into my website where the user of my website can interact with their Facebook friends.

But how?

As the concept of my website is to show that one person's meal intake that contains meat can already cause the release of carbon dioxide to the environment. Therefore, if each individual started reducing one meal that contain meat per day, the rate of global warming can be reduced. For example, if your daily meat intake is 3 meals, then you might want to start cutting down one meal and have only 2 meals of meat intake per day. Imagine there is 100 people really doing it, the rate of global warming can be reduced a lot per day.