Thus, between and, GNP per capita in the temperate region grew at an average annual rate of 1. Between and , both regions grew at about 2.
This reflects fast growth in non-temperate zone Asia of 2. At the core of this long-term growth was the continued development of technology, a process that has benefitted the temperate-zone countries much more than the tropics.
Production technology in the tropics has lagged behind temperate-zone technology in the two critical areas of agriculture and health. The difficulty of mobilizing energy resources in tropical economies also has contributed to the income gap between climate zones. The problems of applying temperate-zone technological advances to the tropical setting have amplified these factors.
Agricultural, health, and some manufacturing-related technologies that could diffuse within ecological zones could not diffuse across them. For the major crops rice, maize, and wheat , productivity is considerably higher in the temperate-zone than in the tropical-zone: Sachs estimates that in , productivity per hectare of grain produced was approximately 50 percent higher in temperate-zone countries.
In his encyclical on climate change , leaked earlier this week and scheduled to be released on Thursday, Pope Francis remarks that the most severe impacts of climate change will likely fall on those least able to withstand them: the poor. The reasons that the poor living at low latitudes will bear the heaviest burdens of climate change are meteorologically, economically, and geopolitically complex, but they all arise from an inescapable statistical fact: normal temperature ranges in the tropics fall within a narrower range than those in more northern climes, and so any deviation is likely to have more significant effects.
The tropical effects can be grouped into four areas: natural disasters and drought; public health and disease; political instability and conflict; and economics and agriculture.
Disasters : Every time a major storm hits the United States it sparks anew the debate over whether individual weather events are caused by global warming. There is little doubt among scientists, though, that climate change is increasing the frequency and severity of extreme weather events—and that these events wreak the most damage in the tropics , particularly on coastal cities and island nations like the Philippines. Rising seas make storm surges higher; warming oceans help feed typhoons and tropical cyclones; and increased drought ravages croplands in places like sub-Saharan Africa.
Wealthy people in Florida and Hong Kong may see their waterfronts damaged and their real estate values fall; poor people in Bangladesh and the Philippines will see their homes and their livelihoods destroyed. Disease: Warmer temperatures and wetter months will accelerate the proliferation of tropical diseases, particularly insect-borne ones like malaria, which kills more than , people a year, almost all of them in the tropics, and dengue.
The other part of the geography hypothesis is that the tropics are poor because tropical agriculture is intrinsically unproductive. Tropical soils are thin and unable to maintain nutrients, the argument goes, and emphasizes how quickly these soils are eroded by torrential rains. There certainly is some merit in this argument, but the prime determinant of why agricultural productivity — agricultural output per acre — is so low in many poor countries, particularly in sub-Saharan Africa, has little to do with soil quality.
Rather, it is a consequence of the ownership structure of the land and the incentives that are created for farmers by the governments and institutions under which they live. Another influential version of the geography hypothesis is advanced by the ecologist and evolutionary biologist Jared Diamond.
He argues that the origins of intercontinental inequality at the start of the modern period, five hundred years ago, rested in different historical endowments of plant and animal species, which subsequently influenced agricultural productivity.
In some places, such as the Fertile Crescent in the modern Middle East, there were a large number of species that could be domesticated by humans. Elsewhere, such as the Americas, there were not. Having many species capable of being domesticated made it very attractive for societies to make the transition from a hunter-gatherer to a farming lifestyle. As a consequence, farming developed earlier in the Fertile Crescent than in the Americas. Population density grew, allowing specialization of labor, trade, urbanization, and political development.
Crucially, in places where farming dominated, technological innovation took place much more rapidly than in other parts of the world. Thus, according to Diamond, the differential availability of animal and plant species created differential intensities of farming, which led to different paths of technological change and prosperity across different continents.
For example, Diamond argues that the Spanish were able to dominate the civilizations of the Americas because of their longer history of farming and consequent superior technology. But we now need to explain why the Mexicans and Peruvians inhabiting the former lands of the Aztecs and Incas are poor. While having access to wheat, barley, and horses might have made the Spanish richer than the Incas, the gap in incomes between the two was not very large.
The average income of a Spaniard was probably less than double that of a citizen of the Inca Empire. Yet nothing of the sort happened. On the contrary, in the nineteenth and twentieth centuries, a much larger gap in incomes between Spain and Peru emerged. Today the average Spaniard is more than six times richer than the average Peruvian. Economists and co-authors William Masters of Purdue University and Margaret McMillan of Tufts University, say frost plays two important roles: It helps farmers increase agricultural productivity, and it helps people control disease, particularly malaria.
Since antiquity, observers have noted differences between people living in the tropics and those living in temperate zones. In B. And from at least the time of Adam Smith's "Wealth of Nations" to 's Pulitzer Prize-winning book by Jared Diamond, "Guns, Germs, and Steel," people have speculated why some areas of the globe are wealthy while others seem destined for poverty.
But these are countries that have totalitarian governments and exist in isolation," Masters says. Masters and McMillan took advantage of recent advances in global information systems data about the earth's climate to take another look at the ancient question.
They discovered that the factors differentiating wealthy countries from poor included annual hard frosts. Cold weather has two major effects, the researchers say: The temperate areas have historically had less disease and better agriculture, at least from the point where the citizens of those countries learned how to take advantage of the seasonal frost cycle.
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