I am in China this week, where big numbers can be overwhelming.

I am currently in Shanghai, a city of 27,000,000 people, sitting on a high-speed train headed to Beijing, a city of 22,000,000. Our own NYC, the best city in the world, has a mere 20 million in the metropolitan statistical area. China has five cities with more than 10 million people as of this writing. This set me to thinking about other big numbers facing humanity.

We currently share Earth with 7,250,000,000 brothers and sisters. Another 2,000,000,000 will be joining us for dinner in less than 35 years. This year, 1,400,000 children will die from preventable waterborne disease. Another 860,000 will die from malnutrition, while we waste more than 30 percent of the food we produce each day.

Around the world today, 1,200,000,000 people live in water scarce areas. Another 500,000,000 people will likely experience water scarcity in the next decade due to climate change impacts. Amazingly, 1,600,000,000 people live in areas with plenty of water, but do not have access to clean water due to lack of infrastructure. This is called economic water scarcity. Combined, by 2025 more than 2,400,000,000 people (30% of humanity) could live under water scarce conditions.

The primary driver for loss of biodiversity is land use change; 70 percent of land use change is from forest or prairie to agriculture. More than 40 percent of tropical and subtropical forests and 45 percent of temperate forests worldwide have been converted to croplands and rangelands in the past 50 years. We currently use 43% of Earth’s surface for agricultural production (including grazing and pasture). If we want to save other living things for the next generation we must stop converting lands for agricultural production; that means intensifying yield on the land we currently have in production.

We need to focus our attention on these big number challenges. The solutions to these challenges must come from a combination of all of our knowledge traditions – sciences, humanities, technologies, arts. We must create new ways of understanding these problems by combining the lenses of our disciplines.  Big number problems can be intimidating, but they can also be exhilarating. Let’s get to work!