摘要:

AbstractA simple empirical index of human thermal comfort is applied to the problem of assessing China's human climate resource. Considerable spatial and temporal variation of the human climate resource occurs in China. The human climate resource is discussed in terms of its synoptic‐scale climatic controls and the implications the spatial and temporal variations of the resource holds for the rapidly developing tourist industry in Chin

ISSN:0899-8418    

DOI:10.1002/joc.3370130702

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

摘要:

AbstractDaily data of (a) rainfall amount, (b) prevailing wind direction, (c) wind speed, (d) mean temperature, and (e) mean relative humidity of 19 stations in Bangladesh for the months May through to October, for the period 1958 through to 1987, have been analysed in order to determine various spatio‐temporal patterns of the arrival and withdrawal dates of the summer monsoon in the country. Statistical characteristics of these dates have been presented.The summer monsoon arrives first in the extreme south‐eastern part of the country, and initially moves towards the north. After being diverted by the Meghalaya Plateau, the flow turns towards the west. The mean arrival date of the summer monsoon in the extreme south‐eastern coastal part and in the extreme north‐western part are 2 June and 15 June, respectively. Withdrawal of the summer monsoon proceeds in the opposite direction to the arrival. Mean withdrawal dates of the summer monsoon from the extreme north‐western part and extreme south‐eastern part of the country are 30 September and 17 October, respectively. Standard deviations of both arrival and withdrawal dates in different parts of the country vary from 7 to 10 days.Probabilistic early dates of arrival of the summer monsoon in Cox's Bazar area in 1 year out of 4 years, 10 years, and 25 years are 28 May, 23 May, and 19 May, respectively. Probabilistic late dates of arrival in 1 year out of 4 years, 10 years, and 25 years are 8 June, 13 June, and 16 June, respectively.Probabilistic early dates of complete withdrawal of the summer monsoon from Bangladesh in 1 year out of 4 years, 10 years, and 25 years are 10 October, 5 October, and 1 October, respectively. Probabilistic late dates of complete withdrawal in 1 year out of 4 years, 10 years, and 25 years are 23 October, 28 October, and November 1, r

ISSN:0899-8418    

DOI:10.1002/joc.3370130703

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

摘要:

AbstractRegionalization of daily rainfall in Sri Lanka was examined using orthogonal factor analysis (OFA) based on daily rainfall data of 42 stations for a 15‐year period (1971–1985). The number of potential rainy days was computed from the original data matrix and subjected toS‐mode OFA. The first 10 orthogonal factors were shown as highly significant, explaining 65.1 per cent of the total variance of the whole data matrix, where the level of eigenvalues represented was>1.0. Noticeably, the 10 orthogonal factors clearly revealed the different homogeneous daily rainfall regions in Sri Lanka (labelled as A to J), according to the orthogonal factor high loadings matrix. Delimitation of the daily rainfall regions was carried out in accordance with the ‘variance boundaries’ resulting from the rotated factor loadings matrix. The number of potential rainy days has been identified for each region, showing an increasing trend with elevation. The probability of rainy days, wet spells and their mean length have been computed separately on a monthly and yearly basis in order to analyse the nature of the daily rainfall reliability in each region. The main factors for the daily rainfall fluctuation patterns in Sri Lanka are the typical monsoon rainfall, the dominant influence of the Inter Tropical Convergence Zone and t

ISSN:0899-8418    

DOI:10.1002/joc.3370130704

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

摘要:

AbstractDaily particulate concentrations in the Desert South‐west from 1984 to 1988 are analysed using a synoptic climatology based upon tropospheric thermal, moisture, and flow conditions. Using a combination of principal components analysis and cluster analysis, 13 distinct synoptic types (clusters) are identified that correspond to seasonal variations in the atmosphere's general circulation. These include summer clusters, which reflect monsoonal and non‐monsoonal conditions, winter clusters defined by the positions of the polar and subtropical jets and shortwave ridges and troughs, and clusters that predominate in the transition seasons.Particulate concentrations vary significantly by synoptic type. Three clusters have poor air quality. ‘Summer monsoon’ days have high humidity and cloud cover, conditions that encourage aerosol growth. ‘Continental high’ days have a slow‐moving anticyclone centred over the Great Basin that traps particulates within the boundary layer. ‘Rockies ridge’ days are associated with strong south‐westerly flow and the advection of regional haze from southern California into the Desert South‐west. In all of these clusters, high humidity or cloud cover enhance particulate growth. Good air quality in the summer occurs on monsoonal ‘break’ days when relative humidity and cloud cover decrease. In the winter, good air quality occurs when Arctic or continental polar air masses are present, or when either the polar or subtropical jets are strong and positioned over the South‐west. In some of these latter situations, widespread precipitation removes particulates through wet deposition.These results suggest that the Navajo Generating Station (NGS), a large coal‐fired power plant on the Arizona‐Utah border, does not contribute significantly to air quality degradation in the Grand Canyon National Park, Arizona. Most of the days with high particulate levels are associated with transport from southern California or unstable summer days with high humidity and contributions from many point and regional sources. There may be some contribution from the NGS on ‘continental high’ days, but when this cluster occurs on consecutive days, air quality improves rather than declines. This research provides a useful framework for future mesoscale modelling studies

ISSN:0899-8418    

DOI:10.1002/joc.3370130705

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

摘要:

AbstractMeasurements from the first comparative study of climate over Amazonian tropical forest and an embedded deforested clearing are presented. Observations comprise a continuous 60‐day run of data from mid‐October to mid‐December 1990, covering the end of the dry season and the beginning of the wet season. Mean hourly observations are calculated for the whole period; and for two 10‐day periods, one in the dry season and one at the start of the wet season. Much greater variation in weather variables was observed at the clearing compared with over the forest. While the mean values of temperature and specific humidity deficit differed by less than 1°C and 1 g kg−1respectively, their daily ranges at the clearing were twice those at the forest. Mean daily albedo of the forest was 13.1 per cent, agreeing well with other tropical forest measurements, and of the clearing was 16.3 per cent, somewhat lower than the values currently being used in GCMs. The surface energy balance was investigated and mean available energy calculated for each site. The significant difference in the daily pattern of net radiation between the sites was found to be at least as much due to differences in the longwave radiation balance as to differences in albedo. The diurnal pattern of net radiation therefore changed between dry and wet periods as the higher plant water stress experienced by clearing vegetation altered the daily tempera

ISSN:0899-8418    

DOI:10.1002/joc.3370130706

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

摘要:

AbstractSimulations are presented for the effects of artificial heat sources and ground shading by buildings on air temperature variations in the urban canopy layer. An idealized urban cluster composed of repeated street canyons oriented east‐west with an aspect ratio of 0.5 is used to evaluate these effects. The simulations by the cluster thermal time constant model show that a daily mean artificial heat flux of 11 Wm−2causes an almost invariant temperature rise of 0.7 K around‐the‐clock. Conversely, increasing the shade area in the streets by means of vertical screens fitted at the building roof‐level can produce a pronounced temperature lowering

ISSN:0899-8418    

DOI:10.1002/joc.3370130707

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

ISSN:0899-8418    

DOI:10.1002/joc.3370130708

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

ISSN:0899-8418    

DOI:10.1002/joc.3370130710

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

ISSN:0899-8418    

DOI:10.1002/joc.3370130711

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY

ISSN:0899-8418    

DOI:10.1002/joc.3370130701

出版商:John Wiley&Sons, Ltd.    

年代:1993

数据来源: WILEY