Doing all we can to combat climate change comes with numerous benefits, from reducing pollution and associated health care costs to strengthening and diversifying the economy by shifting to renewable energy, among other measures.

Humans are now the most numerous mammal on the planet. There are more humans than rats or mice. Humans have a huge ecological footprint, magnified by their technology.

Despite the international scientific community's consensus on climate change, a small number of critics continue to deny that climate change exists or that humans are causing it. Widely known as climate change "skeptics" or "deniers," these individuals are generally not climate scientists and do not debate the science with the climate scientists.

Hydraulic fracturing requires massive amounts of water. Disposing of the toxic wastewater, as well as accidental spills, can contaminate drinking water and harm human health.

We must pay greater attention to keeping our bodies and minds healthy and able to heal. Yet we are making it difficult for our defences to work. We allow things to be sold that should not be called food. Many have no nutritive value and lead to obesity, salt imbalance, and allergies.

I see a world in the future in which we understand that all life is related to us and we treat that life with great humility and respect.

For the first time since life appeared on earth, one species- us- is single-handedly altering the physical, chemical and biological nature of earth. We have become a force of nature