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Climate characteristics over southern highlands Tanzania
No full textJournal articleThis study was conducted to examine the climate characteristic of southern highland Tanzania (Latitude 6°S - 12°S and Longitude 29°E - 38°E). The study findings reveal that rainfall over the region is linked with SST over the Indian Ocean, where warmer (cooler) western Indian Ocean is accompanied by high (low) amount of rainfall over Tanzania. During wet (dry) years, weaker (stronger) equatorial westerlies and anticyclone (cyclonic) anomaly over the southern tropics act to reduce (enhance) the export of equatorial moisture away from East Africa. The wettest (driest) season was found to be 1978/79 (1999/00) which can be classified as the severely wet (moderate drought). Two different modes of rainfall have been identified at time scale of 1.5 and 6 years which have been associated with the quasi biennial oscillation (QBO) and El Nino Southern Oscillation (ENSO), respectively
Climate characteristics in Tanzania and its relationship with general circulation and Sea Surface Temperature (SST)
No full textDissertationThis study was conducted to examine the climate characteristic of southern highland
Tanzania (Latitude 6°S-12°S and Longitude 29°E-38°E). In order to meet the objectives
of this study, monthly average rainfall data from Tanzania Meteorological Agency
(TMA) and global marine environmental data, which consists gridded monthly sea
surface temperature (SST), sea level pressure (SLP) and zonal (U) and meridional (V)
wind components from National Oceanic and Atmospheric Administration (NOAA)
Earth System Research Laboratory were used. The rainfall data was used to develop
Standardized Precipitation Index (SPI) which was then used to find correlation with
global marine environmental parameters. Wavelet method was used to analyze
variations of power within the time series and dominant modes of rainfall variability
The study findings revealed that rainfall over the region is linked with SST over the
Indian Ocean, where warmer (cooler) western Indian Ocean is accompanied by high
(low) amount of rainfall over Tanzania. During wet (dry) years, weaker (stronger)
equatorial westerlies and anticyclone (cyclonic) anomaly over the southern tropics act
to reduce (enhance) the export of equatorial moisture away from East Africa. Not only
that, but also moisture influx from the northeast Indian monsoon has significant
influence on the rainfall over the region. During the wet years, strong northeasterly
Indian monsoon is evident over most of Tanzania while during the dry year the
northeasterly is seen to turn north hence denying moisture influx over Tanzania. In addition, increased (decreased) low level moisture influx from gulf of Guinea and
Congo basin tend to occur during the wet (dry) seasons, leading to enhanced (reduced)
low level moisture convergence over western part of Tanzania.
Results suggest the wettest season in record to be 1978/79 which can be classified as the
“Severely wet” and the driest season in record to be 1999/00 which can be classified as
“Moderate drought”. Different dominant periodicity modes have been observed over
the study period, but two of them seem to be more dominant over the whole study
period. These modes of rainfall have been identified at time scale of 2 and 7 years which
may be associated with the quasi biennial oscillation (QBO) and El Nino Southern
Oscillation (ENSO) respectively. Moreover, key areas over the Ocean have been
identified to be in between 5°S-18°S and 58°E-70°E for Indian Ocean and 2°N-17°S,
5°W-IO°E for Atlantic Ocean.
The study recommends a closer follow-up on the local variation of SST over these key
areas as they can help in forecasting year to year rainfall variability. Also responsible
institutions in the government should make use of the findings from this study as a
benchmark in improving agriculture sector and vigilance for extreme events
Climate characteristics over southern highlands Tanzania
No full textThis study was conducted to examine the climate characteristic of southern highland Tanzania (Latitude 6°S - 12°S and Longitude 29°E - 38°E). The study findings reveal that rainfall over the region is linked with SST over the Indian Ocean, where warmer (cooler) western Indian Ocean is accompanied by high (low) amount of rainfall over Tanzania. During wet (dry) years, weaker (stronger) equatorial westerlies and anticyclone (cyclonic) anomaly over the southern tropics act to reduce (enhance) the export of equatorial moisture away from East Africa. The wettest (driest) season was found to be 1978/79 (1999/00) which can be classified as the severely wet (moderate drought). Two different modes of rainfall have been identified at time scale of 1.5 and 6 years which have been associated with the quasi biennial oscillation (QBO) and El Nino Southern Oscillation (ENSO), respectively
Climate characteristics over southern highlands Tanzania
No full textJournal articleThis study was conducted to examine the climate characteristic of southern highland Tanzania (Latitude 6°S - 12°S and Longitude 29°E - 38°E). The study findings reveal that rainfall over the region is linked with SST over the Indian Ocean, where warmer (cooler) western Indian Ocean is accompanied by high (low) amount of rainfall over Tanzania. During wet (dry) years, weaker (stronger) equatorial westerlies and anticyclone (cyclonic) anomaly over the southern tropics act to reduce (enhance) the export of equatorial moisture away from East Africa. The wettest (driest) season was found to be 1978/79 (1999/00) which can be classified as the severely wet (moderate drought). Two different modes of rainfall have been identified at time scale of 1.5 and 6 years which have been associated with the quasi biennial oscillation (QBO) and El Nino Southern Oscillation (ENSO), respectively
Climate characteristics in Tanzania and its relationship with general circulation and Sea Surface Temperature (SST)
No full textDissertationThis study was conducted to examine the climate characteristic of southern highland
Tanzania (Latitude 6°S-12°S and Longitude 29°E-38°E). In order to meet the objectives
of this study, monthly average rainfall data from Tanzania Meteorological Agency
(TMA) and global marine environmental data, which consists gridded monthly sea
surface temperature (SST), sea level pressure (SLP) and zonal (U) and meridional (V)
wind components from National Oceanic and Atmospheric Administration (NOAA)
Earth System Research Laboratory were used. The rainfall data was used to develop
Standardized Precipitation Index (SPI) which was then used to find correlation with
global marine environmental parameters. Wavelet method was used to analyze
variations of power within the time series and dominant modes of rainfall variability
The study findings revealed that rainfall over the region is linked with SST over the
Indian Ocean, where warmer (cooler) western Indian Ocean is accompanied by high
(low) amount of rainfall over Tanzania. During wet (dry) years, weaker (stronger)
equatorial westerlies and anticyclone (cyclonic) anomaly over the southern tropics act
to reduce (enhance) the export of equatorial moisture away from East Africa. Not only
that, but also moisture influx from the northeast Indian monsoon has significant
influence on the rainfall over the region. During the wet years, strong northeasterly
Indian monsoon is evident over most of Tanzania while during the dry year the
northeasterly is seen to turn north hence denying moisture influx over Tanzania. In addition, increased (decreased) low level moisture influx from gulf of Guinea and
Congo basin tend to occur during the wet (dry) seasons, leading to enhanced (reduced)
low level moisture convergence over western part of Tanzania.
Results suggest the wettest season in record to be 1978/79 which can be classified as the
“Severely wet” and the driest season in record to be 1999/00 which can be classified as
“Moderate drought”. Different dominant periodicity modes have been observed over
the study period, but two of them seem to be more dominant over the whole study
period. These modes of rainfall have been identified at time scale of 2 and 7 years which
may be associated with the quasi biennial oscillation (QBO) and El Nino Southern
Oscillation (ENSO) respectively. Moreover, key areas over the Ocean have been
identified to be in between 5°S-18°S and 58°E-70°E for Indian Ocean and 2°N-17°S,
5°W-IO°E for Atlantic Ocean.
The study recommends a closer follow-up on the local variation of SST over these key
areas as they can help in forecasting year to year rainfall variability. Also responsible
institutions in the government should make use of the findings from this study as a
benchmark in improving agriculture sector and vigilance for extreme events
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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