Humans emit roughly 30 to 40 billion tons of the greenhouse gas, carbon dioxide, into the atmosphere each year. If we keep it up, Earth will continue to heat up and ultimately devastate our way of life.

So what can we do about it?

Most scientists agree that we need a way to capture some of that CO2 out of the atmosphere. One idea is to plant lots of trees. Trees use CO2 in order to grow. They also release oxygen, so it's a win-win.

But recent reports indicate that we simply can't grow enough trees to capture the necessary amount of CO2 that would help us meet the goals set by the Paris Agreement.

In truth, we would have to cover the entire contiguous US with trees just to capture 10% of the CO2 we emit annually.

There's just not enough room on this planet to have the farmland it takes to feed the world plus the space to plant the necessary number of trees.

In other words, many of us would starve if we tried using trees to solve our emissions problem.