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Friday, October 29, 2010

The Humboldt current and Alexander von Humboldt


There is an ocean current that flows along the Peruvian Coast. It is called as Humboldt Current, after the Prussian Explorer Alexander von Humboldt. This ocean current serves as a classical example of an eastern boundary current and features a typically wide and slow equator ward transport of cold water along the coast of South America.

The Peruvian Current is the largest upwelling system among the eastern boundary currents. What do you mean by upwelling? Upwelling is a process in which cold nutrient-rich water rises to the surface from the ocean depths.

The North- western alignment of the Andes Mountain along the Peruvian Coast forces the south –east Trade Winds to blow northwards. This condition causes an offshore flow in the surface layers of the marine water. This makes it one of the most productive upwelling systems in the world causing cold nutrient rich water to appear along the coast. It supports an extra- ordinary abundance of marine life. The Peruvian Ocean Current System accounts for approximately 18 to 20 percent of the tidal fish catch worldwide. The weakening of the Peruvian Current System allows the counter current to move southwards. It disrupts the coastal upwelling which normally occurs along the coast and creating a condition known as El-Nino. El- Niño is the warming of  sea surface temperatures in the equatorial pacific ocean which influences atmospheric circulation, and consequently rainfall and temperature in specific areas around the world.

El-Niño is the Spanish world which means Christ Child. It indicates the appearance of a warm ocean current of the South American Coast around the Christmas. Approximately 14 El-Niño events affected the world between 1950 and 2003. On the reverse side, is La-Nina which is the cooling of sea surface temperatures in the equatorial Pacific Ocean, and which influences the atmospheric circulation, and consequently the rainfall and temperature in specific areas around the world. It is the opposite of El-Nino.Now let us talk about Alexander Humboldt, whose contributions will be remembered by the History of Natural Sciences till eternity.Here is a detail, directly quoted from his Biography from macroevolution.net.

Alexander von Humboldt (1769-1859)

Alexander von Humboldt (1769-1859), a Prussian naturalist, scientific explorer, polyglot, and polymath. His full name was Friedrich Wilhelm Heinrich Alexander Freiherr von Humboldt.He was borne in Berlin on September 14, 1769.

The last great scientific generalist, Humboldt made important contributions to nearly every branch of the natural sciences. Indeed, he believed that no organism or phenomenon could be fully understood in isolation. Living things, the objects of biological study, had to be considered in conjunction with data from other fields of research such as meteorology and geology. His object was to measure every aspect of nature, and he did so with the finest instruments then available.

Alexander von Humboldt was born in Berlin in 1769 (the same birth year as Georges Cuvier). He was raised, after the age of nine, by his mother — his father, a Prussian military officer, having died in 1779. During his early years, Alexander was tutored at home together with his brother Wilhelm. He went on to study at the Freiberg Academy of Mines under the famous geologist A. G. Werner.

After graduation, he worked for a time as a mine inspector. But when his mother died, and he became financially independent, he decided to leave government service. Together with botanist Aimé Bonpland, he began planning an expedition to Latin America, a region then poorly known to European science. The two traveled to Madrid, obtained permission for their journey, and set out. The year was 1799.

The story of their journey (see map below) is told in the famous Personal Narrative of Travels to the Equinoctial Regions of the New Continent. In the Narrative, Humboldt and Bonpland report on their travels throughout much of Central and South America, where they scaled the heights of the Andes and penetrated the unknown depths of the rain forests.

They recorded information on geology, geography, botany, archeology, zoology, oceanography, and other fields of natural science. Many organisms first entered the scientific literature in their reports, for example, the Humboldt Squid . Others, such as the Amazon River Dolphin, they found in previously unknown locations.

Humboldt also studied the customs, politics, languages, and economies, of the countries they visited. As José de la Luz y Caballero put it, "Columbus gave Europe a New World; Humboldt made it known in its physical, material, intellectual, and moral aspects." His writings would spark the dreams of future generations of scientists. Late in life, Charles Darwin said Humboldt and Bonpland's Narrative had been the primary inspiration for his own decision to ship on board the Beagle and sail around the world.

Humboldt had incredible mental and physical energies. At the age of 59 he completed a 9,000-mile exploratory trek across much of Russia. Six years later, when he was 65 years old, he began his five-volume Cosmos, a massive work in which he attempted to organize everything then known about the entire universe. Like Carl Sagen's later book of the same name, Humboldt intended Cosmos to be a popular scientific book that would provide the general public with an overview of the whole natural world. He hoped it would inspire a wider appreciation of science and scientific study. A huge success, it was eventually translated into most European languages. But Humboldt's flame burnt out before he could finish the last volume — he died on May 6, 1859, still writing, at the age of 89.