• ALGAE
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• v.26 no.2
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• pp.109-140
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• 2011

Taylor's (1960) floristic treatment of the benthic marine algae of the tropical and subtropical western Atlantic and Wynne's (2011) "checklist: third revision" serve as benchmarks in a review of changes made in the past half-century period. There has been a great increase in the number of recognized taxa of red, brown and green algae at all taxonomic ranks: from 758 to 1,393 species, an increase of 84%; from 231 to 406 genera, an increase of 75%; and from 63 to 106 families, an increase of 68%. In regard to recognized infraspecific taxa, the increase was less dramatic, from 140 to 185, thus a 32% change in the 50-year period. This review addresses the question: What factors were responsible for this proliferation of taxa that are now recognized in this domain of the tropical and subtropical western Atlantic? The answer is that many reasons contributed to these changes. Foremost among these causes have been the advances in gene-sequencing technologies. Revised phylogenetic relationships have led to many genera being divided into more than one genus, as well as new families and orders being delineated. Numerous examples of cryptic species have been discovered by gene-sequence and DNA-bar coding studies. This trend is depicted by case studies. Examples of genera being divided are Galaxaura, Liagora and Laurencia. Tricleocarpa and Dichotomaria have been segregated from Galaxaura. Trichogloeopsis, Ganonema, Izziella, Yamadaella, and Titanophycus have been segregated from Liagora. Chondrophycus, Osmundea, Palisada, and Yuzurura have been segregated from Laurencia. Examples are given of other genera present in this region of the western Atlantic that have been split up. Many genera have increased in terms of the number of species now assigned to them. Taylor's (1960) treatment recognized only two species in Hypoglossum, whereas Wynne's (2011) checklist contained a total of 9 species of Hypoglossum. Taylor's account included only two species of Botryocladia, but this number had grown to 15 in Wynne's checklist. Examples of new genera and species occurring in the region of the western Atlantic are given, and examples of taxa being newly reported for this domain are provided. An increase in the number of phycologists in Latin and South America, exploration of previously unexplored regions, and the increasing use of SCUBA for collecting and at greater depths have all contributed to the increase in the number of algal taxa that are now recognized as occurring in the tropical and subtropical western Atlantic.

• Journal of the Korean earth science society
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• v.34 no.3
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• pp.224-234
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• 2013

This study examined a strong positive correlation between the North Atlantic Oscillation (NAO) index during June and the total tropical cyclone (TC) genesis frequency in the western North Pacific during July and August. To investigate a possible cause for this relationship, the mean difference between the highest positive NAO years and the lowest negative NAO years was analyzed by dividing into when the El Ni$\tilde{n}$o and La Ni$\tilde{n}$a years were included and when the El Ni$\tilde{n}$o and La Ni$\tilde{n}$a years were not included. When the El Ni$\tilde{n}$o and La Ni$\tilde{n}$a years were included, for the positive NAO years, the TCs mostly occurred in the northwestern region of tropical and subtropical western Pacific, and showed a pattern that migrate from the sea northeast of the Philippines, pass the East China Sea, and move toward the mid-latitudes of East Asia. In contrast, for the negative NAO years, the TCs mostly occurred in the southeastern region of tropical and subtropical western Pacific, and showed a pattern that migrate westward from the sea southeast of the Philippines, pass the South China Sea, and move toward the southern coast of China and Indochinese peninsula. These two different TC migration patterns affect the recurving location of TC, and for the positive NAO years, the recurving of TC was averagely found to take place in the further northeast. In addition, the migration patterns also affect the TC intensity, and the TCs of positive NAO years had stronger intensity than the TCs of negative NAO years as sufficient energy can be absorbed from the ocean while moving north in the mid-latitudes of East Asia. The TCs of negative NAO years showed weak intensity as they get weaken or disappear shortly while landing on the southern coast of China and the Indochinese peninsula. On the other hand, the above result of analysis is also similarly observed when the El Ni$\tilde{n}$o and La Ni$\tilde{n}$a years were not included.