We humans share a very flawed sense of proportion. We tend to consistently underestimate the relevance of certain events and overestimate others. Social psychologists refer to the general phenomena as cognitive bias.
Environmentalists stay awake at night worrying about global warming. One of the worst-case scenarios of global warming involves the release of methane, a greenhouse gas 21 times more potent than CO2, currently trapped under the sea. Recent studies reveal that thawing lakes of the northern hemisphere are releasing methane at an alarming rate. The more Earth temperatures increase, the more frozen lakes and permafrost thaw, the more methane is released into the atmosphere, the bigger the greenhouse effect, the more Earth temperatures rise. This vicious cycle, if unchecked, could wipe out most rainforests, destroy the fertility of many soils and leave the Arctic ice-free even in midwinter. Entire regions will become uninhabitable. Depending on where you live, your country might enter into a war with a neighboring country over fresh water resources.
Study of ice cores from Greenland and Antarctica show that increases of methane concentrations have occurred the past. According to the anthropic principle, given that life exists on Earth, especially in the form of Homo sapiens, conditions on Earth must be amenable to carbon-based life forms, including us. However, as anyone involved in the stock market knows, past performance is no guarantee for the future. Indeed, the Earth has sustained life for millions of years, however, that is no proof that it will necessarily continue do so in the future.
How is it that we don't seem to worry more about the environment? Is it because the problem is too big to lay on our frail shoulders? Is it because we lack proof about the impending catastrophe? Is it because of insufficient media coverage? Is it because we subconsciously know that, like our own death, Earth's demise is inevitable, so we don't wish too waste time worrying about it? What are the cognitive biases that we need to overcome in order to react more effectively?