[Article from the Papua New Guinea National Newspaper - Wednesday April 23, 2008]
El-Nino blamed for poor harvest
DESPITE PNG recording low agriculture outputs during past national election years, election and politics are not to be blamed for these poor crop harvests, an Australian academic has said.
Dr Roderick Duncan, a marketing lecturer at the Charles Sturt University in Australia, in a recent Pacific Economic Bulletin issue, said his study has found that there had been declines in the production for PNG’s four main tree crops coffee, cocoa, oil-palm and copra during election years.
The election years covered in the study include 1977, 1982, 1987, 1992, 1997 and 2002.
However, based on calculations using models with data from PNG sources, Dr Duncan found that the four tree crop harvest declines in those years were not related to politics and the national elections, but were coincidently caused by the weather phenomenon known as the El Nino-Southern Oscillation (ENSO) during those election years.
ENSO results from the seasonal air pressure difference between Tahiti and Darwin, Australia, with high air pressure over Australia and low air pressure over Tahiti.
This brings weak trade winds resulting in droughts to countries in the Pacific like PNG.
Major ENSO episodes, he said, occurred in those years, which resulted in low rainfall during those years, affecting coffee, cocoa, oil-palm, and copra harvests.
“By estimating the supply functions of PNG cash-crop producers, what was discovered was that blame more likely lay with the ENSO episodes that occurred recently and coincided with low values with the elections of 1982 and 1997,” Dr Duncan said.
“It is this coincidence that could have led some observers to believe that harvests and elections were linked,” he said.
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The above claim by Dr Duncan is quite interesting as reported in the Papua New Guinea National Newspaper today [Wednesday 23 April, 2008].
Where there is a lingering high atmospheric pressure system over an area, drought conditions can easily develop. One would most likely observe that air moisture and humidity will tend to decrease or is reduced dramatically. Furthermore, the sky usually have less cloud cover so there will be increased evapo-transpiration [evaporation from ground surfaces and from plants and vegetation]. Ground surface temperatures also increases during the day as insolation [incoming short-wave solar radiation] from the sun is not hindered by cloud cover. In the night, especially in areas like Kandep in the Enga Province of the Highlands of Papua New Guinea and other high attitude areas such as Togoba area of the Western Highlands of Papua New Guinea, night time temperatures will drop quite dramatically giving rise to early morning frosts which can be quite severe at times. As moisture in the air and soil continues to be reduced over an area by a lingering high atmospheric pressure system, one would generally observe that in such an area droughts can become established. [John Nirenga, April 23, 2008].
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El-Nino blamed for poor harvest
DESPITE PNG recording low agriculture outputs during past national election years, election and politics are not to be blamed for these poor crop harvests, an Australian academic has said.
Dr Roderick Duncan, a marketing lecturer at the Charles Sturt University in Australia, in a recent Pacific Economic Bulletin issue, said his study has found that there had been declines in the production for PNG’s four main tree crops coffee, cocoa, oil-palm and copra during election years.
The election years covered in the study include 1977, 1982, 1987, 1992, 1997 and 2002.
However, based on calculations using models with data from PNG sources, Dr Duncan found that the four tree crop harvest declines in those years were not related to politics and the national elections, but were coincidently caused by the weather phenomenon known as the El Nino-Southern Oscillation (ENSO) during those election years.
ENSO results from the seasonal air pressure difference between Tahiti and Darwin, Australia, with high air pressure over Australia and low air pressure over Tahiti.
This brings weak trade winds resulting in droughts to countries in the Pacific like PNG.
Major ENSO episodes, he said, occurred in those years, which resulted in low rainfall during those years, affecting coffee, cocoa, oil-palm, and copra harvests.
“By estimating the supply functions of PNG cash-crop producers, what was discovered was that blame more likely lay with the ENSO episodes that occurred recently and coincided with low values with the elections of 1982 and 1997,” Dr Duncan said.
“It is this coincidence that could have led some observers to believe that harvests and elections were linked,” he said.
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The above claim by Dr Duncan is quite interesting as reported in the Papua New Guinea National Newspaper today [Wednesday 23 April, 2008].
Where there is a lingering high atmospheric pressure system over an area, drought conditions can easily develop. One would most likely observe that air moisture and humidity will tend to decrease or is reduced dramatically. Furthermore, the sky usually have less cloud cover so there will be increased evapo-transpiration [evaporation from ground surfaces and from plants and vegetation]. Ground surface temperatures also increases during the day as insolation [incoming short-wave solar radiation] from the sun is not hindered by cloud cover. In the night, especially in areas like Kandep in the Enga Province of the Highlands of Papua New Guinea and other high attitude areas such as Togoba area of the Western Highlands of Papua New Guinea, night time temperatures will drop quite dramatically giving rise to early morning frosts which can be quite severe at times. As moisture in the air and soil continues to be reduced over an area by a lingering high atmospheric pressure system, one would generally observe that in such an area droughts can become established. [John Nirenga, April 23, 2008].
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