Harold Nkhoma, left, and Werani Chilenga, with their antiquated meteorological gear in Blantyre, Malawi, where most weather data simply go unrecorded. (Joao Silva for The New York Times)
The climate divide: How rich and poor countries are dealing with global warming
Over the last few decades, as scientists have intensified their studies of the human effects on climate and of the effects of climate change on humans, a common theme has emerged: in both respects, the world is a very unequal place.
In almost every instance, the people most at risk from climate change live in countries that have contributed least to the atmospheric buildup of carbon dioxide and other greenhouse gases linked to the recent warming of the planet.
Those most vulnerable countries also tend to be the poorest. And the countries that face the least harm - and are best equipped to deal with the harm they do face - tend to be the richest.
To advocates of unified action to curb greenhouse gases, this growing realization is not welcome news.
"The original idea was that we were all in this together, and that was an easier idea to sell," said Robert Mendelsohn, an economist at Yale University.
But the research is not supporting that. We're not in it together."
The large industrialized countries are more resilient partly because of geography; they are mostly in mid-latitude regions with Goldilocks climates - neither too hot nor too cold.
Many enjoy gifts like the thick rich soil and generous growing season of the American corn belt or the forgiving weather of France and New Zealand.
But a bigger factor is their wealth - wealth built at least partly on a century or more of burning coal, oil and the other fossil fuels that underlie their mobile, industrial, climate-controlled way of life.
The United States, where just 4 percent of the economy is in agriculture, can endure a climatic setback far more easily than a country like Malawi, where 90 percent of the population is rural and where about 40 percent of the economy is driven by rain-fed agriculture.
As big developing countries like China and India climb out of poverty, they emit their own volumes of greenhouse gases; China is about to surpass the United States in annual emissions of carbon dioxide.
But they remain a small fraction of the total human contribution to the atmosphere's natural heat-holding greenhouse effect, which is cumulative because of the long-lived nature of carbon dioxide and some other heat-trapping gases.
China may be a powerhouse now, but it has contributed less than 8 percent of the total emissions of carbon dioxide from energy use since 1850, while the United States is responsible for 29 percent and Western Europe 27 percent.
Disparities like these have prompted a growing array of officials in developing countries and experts on climate, environmental law and diplomacy to insist that the first world owes the third world a climate debt.
"We have an obligation to help countries prepare for the climate changes that we are largely responsible for," said Peter Gleick, a co-founder of the Pacific Institute for Studies in Development, Environment and Security in Berkeley, California.
Around the world, there are abundant examples of how wealth is already enabling some countries to gird against climatic and coastal risks while poverty, geography and history are placing some of the world's most crowded, vulnerable regions directly in harm's way.
Here are four views of the climate divide:
Twice a day, 25-year-old Harold Nkhoma checks a series of gauges at the government's weather station here in Malawi's second-biggest city.
He skips the barometer because its light doesn't work and he can't read the figures. He has waited six months for new batteries.
He ignores the evaporation pan designed to show how quickly water is absorbed into the soil. Peeled-off paint and missing wire mesh have left it useless. And he bypasses the glass sphere that measures the duration of sunshine by burning marks on paper strips.
It has been out of paper for four years.
His supervisor, Werani Chilenga, is disgusted. Broken equipment, outmoded technology, slipshod data and a sparse scattering of weather stations are all his national agency can manage on a $160,000 budget.
"We cannot even know the duration of sunshine in our country for four years, so how can we measure climate change?" asked Chilenga, a meteorological engineer. "Oh, oh, it is pathetic!"
Lack of meteorological data is just one challenge as Malawi struggles to cope with global warming. Add to that lack of irrigation; overdependence on a single crop, maize; shrinking fish stocks; vanishing forests; and land degradation.
Last March, Malawi, one of the world's poorest countries with 14 million people, identified $23 million worth of urgent measures it should take in the next three years. It delivered them to the United Nations program to help poor nations deal with climate change.
