Never before has humanity’s footprint on Earth’s natural systems been so large. We are outstripping available resources from the only habitable planet we know. Since 1950, human population has increased by nearly 200%; fossil fuel consumption by over 550%; and marine fish capture by over 350%. We’ve placed dams on about 60% of the world’s rivers, we’ve cleared nearly half of temperate and tropical forests, we use nearly half of accessible freshwater every year, and we use about half of the planet’s liveable surface to feed ourselves.
Our environment is changing. Atmospheric carbon dioxide levels are rising at a record pace, with the current levels having increased by about 24% since the 1950s. 2016 was Earth's warmest year on record, and 2017 was the warmest one for oceans, which have also experienced a 30% increase in pH since the Industrial Revolution. Pollinators, which are needed for plants and crops to grow, are disappearing worldwide. Biodiversity is rapidly being lost as an estimated 150 species become extinct each day, which is 1,000 times higher than the "natural" or "background" rate.
And it's affecting our health. Climate change, biodiversity loss, deforestation, and other factors affect where, when, and how intensely infectious diseases emerge. Increased drought, declining pollinators, and extreme storms make it harder to grow food, and some crops are also becoming less nutritious because of atmospheric changes, making people more susceptible to malnutrition and disease. Air pollution, whether from industrial emissions or smoke from fires clearing forests for agricultural use, can lead to cardiorespiratory illnesses and other diseases. Hurricanes and other major storms put people’s lives at risk. And witnessing the degradation of our world can have severe consequences for our mental health.
Everything is connected. What we do to the world comes back to affect us, and not always in ways that we would expect. Understanding and acting upon these challenges call for massive collaboration across disciplinary and national boundaries to safeguard our health.