This document discusses 10 major problems facing the natural environment: 1) climate change, 2) pollution, 3) ozone layer depletion, 4) depletion of natural resources, 5) water quality and scarcity issues, 6) deforestation, 7) soil degradation, 8) waste, 9) loss of biodiversity, and 10) population growth. It notes debate around whether climate change is caused by human activity or natural variations, with the IPCC attributing most warming to human greenhouse gas emissions and others arguing solar activity is a primary driver. The document examines how these issues threaten the sustainability of the planet's life support systems.