Climate Change: The Threat to Life and a New Energy Future

American Museum of Natural History, New York City Until 16 August 2009

Rising seas may threaten cities such as New York. Credit: D. FINNIN/AMNH

A thin red line snakes along a wall, rising from below knee level to a height of three metres. The long glowing tube plots global carbon dioxide concentrations from the year 1600 — when the world's population was less than 600 million, goods were transported by wheelbarrow and horse-drawn vehicles, and the estimated atmospheric CO2 concentration was 274 parts per million — until the year 2000. By that time, the world's population had reached more than 6 billion, aeroplanes were plying the skies, and atmospheric CO2 had topped 369 parts per million. Today, that concentration is at more than 385 parts per million, a level not seen on Earth for at least 800,000 years. Earth is also hotter now than at any time in the past four centuries.

With this grand flourish, the American Museum of Natural History in New York opens its new climate-change exhibition, which runs until August 2009. With displays, interactive videos and dioramas, Climate Change clearly and comprehensively provides the facts on global warming. It dispels doubts about the reality of the crisis — of which there are still plenty among the American public.

The exhibition stresses that humans are responsible for the recent rise in CO2, and that this is linked to a 0.8 °C increase in average global temperatures in the past 100 years. A video installation explains how greenhouse gases such as CO2 trap heat, and shows how global temperatures and atmospheric CO2 are rising in tandem. A small model of a coal-powered steam engine, invented by Thomas Newcomen in 1712, ties the rise in CO2 to the start of the Industrial Revolution. A giant, jagged, one-tonne slab of coal reminds us that this dirty fuel, the burning of which generates nearly twice as much CO2 as natural gas, still provides 40% of the world's electrical energy.

The effects of climate change are already obvious: longer, drier droughts in the southwestern United States and the North African Sahel, spring arriving earlier, warmer seas that kill coral — a bleached and lifeless model reef sits in one corner — and shrinking Arctic sea ice. This last consequence has forced polar bears to spend more time on land, and a diorama depicts a stuffed polar bear foraging for food on a pile of snow-sprinkled rubbish — plastic bottles, a discarded television set, a doorless refrigerator. If that sad scene spurs its viewers to change their lifestyles, then the curators suggest plenty of ways to do so. Touch-screen videos invite visitors to click on their current car and see how much carbon it emits. Drive 99 kilometres in a sports utility vehicle every day, and in a year it will cough out more than 14,000 kilograms of CO2 — enough to fill up two-and-a-half hot-air balloons. The same daily distance in a hybrid-fuel economy car will pump out one-third of that amount.

Many other options are offered for combating climate change: ditch the car and take public transport; avoid bottled water; switch to energy-saving light bulbs; line-dry clothes; fly less; install low-flow showers; pay for wind power; plant trees and shrubs. The exhibition also considers broader solutions such as carbon capture and storage; wind power — already supplying Denmark with more than 20% of its electricity; hydropower; geothermal and solar energy. More than 25,000 solar panels are now sold every year in Kenya, where they are used to power television sets and recharge mobile-phone batteries.

A final wall display invites visitors to write or draw their own solutions on postcards. “We need nuclear energy” is followed by “Windmills and solar power, not nuclear — until we have a plan for nuclear waste”. Another exhorts us to “Promote science education — Study Nature!”. But my favourite card offers one simple word: “Vote”.