International Journal of Biometeorology

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Apple phenology occurs earlier across South Korea with higher temperatures and increased precipitation
International Journal of Biometeorology - Tập 65 - Trang 265-276 - 2020
Jung Gun Cho, Sunil Kumar, Seung Heui Kim, Jeom-Hwa Han, Catherine S. Durso, Patrick H. Martin
This study examined relationships between temperature, precipitation, geo-topography, and the spring phenology of Fuji and Hongro apple cultivars along spatial gradients across South Korea. Phenology data was gathered from 2011 to 2014 in 42 uniformly managed research orchards which span a range in climate, latitude, and elevation. We used linear models and spatially explicit forecasts to study apple phenology under climate change scenarios. Given dry winters and complex terrain in South Korea, we hypothesized that, in addition to temperature, precipitation and geo-topographic factors influence apple phenology. We also expected responses to climate variation to be similar between (spatial) and within (temporal) orchards, given the controlled conditions and the use of apple clones in this study. With other factors held constant, phenological sensitivity ranged from − 3.2 to − 3.4 days °C−1 for air temperature and − 0.5 to − 0.6 days cm−1 for March precipitation in a combined model. When modeled without temperature, phenology changed by up to 10 days over the full range in March precipitation. Spring temperatures and precipitation in March had very little cross-correlation (r < 0.05), suggesting these patterns are independent; however, in a combined model including temperature, predicted changes in precipitation over the next 80 years have only a small impact on future apple phenology. Combining the best models with climate forecasts for South Korea, spring phenology continues to occur earlier over the next 80 years, mostly due to warming temperatures but with strong variation between regions. This suggests regionally specific climate change adaptation strategies are needed for future apple production in South Korea.
Seasonal adaptation of thermal and metabolic responses in men wearing different clothing at 10° C
International Journal of Biometeorology - Tập 37 - Trang 36-41 - 1993
Young Hee Lee, Hiromi Tokura
Thermoregulatory responses at ambient temperatures of 20 and 10° C in six male subjects wearing two different kinds of clothing were compared between summer and winter. The two different kinds of clothing were one insulating the upper half of the body lightly and the lower half of the body heavily (clothing A, the weight in the upper and lower halves of the body being, respectively, 489 g and 1278 g) and the other insulating the upper half of the body heavily and the lower half of the body lightly (clothing B: 1212 g and 559 g). The major findings are summarized as follow. (i) Rectal temperature was kept significantly higher in clothing B than in clothing A both in summer and winter. (ii) The fall of rectal temperature was significantly greater in summer than in winter in both types of clothing. (iii) Mean skin temperatures and skin temperatures in the face, chest, thigh and leg were significantly lower atT a of 10° C in summer than in winter in clothing A, while skin temperatures in the face and thigh were also significantly lower atT a of 10° C in summer than in winter in clothing B. (iv) Metabolic heat production was higher in summer than in winter at 20 and 10° C in both types of clothing. (v) The subjects felt cooler and colder toT a of 10° C in summer than in winter in both types of clothing. These different responses occurring between summer and winter are discussed mainly in terms of total conductance and dry heat loss.
Excess of children’s outpatient consultations due to asthma and bronchitis and the association between meteorological variables in Canoas City, Southern Brazil
International Journal of Biometeorology - Tập 63 - Trang 1517-1524 - 2018
Igor Rojahn da Silva, Anderson Spohr Nedel, Júlio Renato Quevedo Marques, Luciano Ritter Nolasco Júnior
The southern Brazilian city of Canoas, situated in the metropolitan region of Porto Alegre, is subject to several annual meteorological phenomena, such as cold fronts and squall lines. Here, we assess the relationship between meteorological conditions and outpatient consultations for asthma or bronchitis in children from Canoas City. Data from outpatient consultations of children (below 9 years), between January/2005 and September/2008, were combined with daily meteorological data from 12UTC (morning) and 18UTC (afternoon). We identified 42 days with an excess of outpatient consultations (peaks). Consultations were negatively correlated with temperature and human thermal comfort index (HTCI) from the 3 previous days based on consultation data at 12 and 18UTC, and positively correlated with atmospheric pressure. A positive correlation with relative humidity was significant only at 12UTC. The highest correlations occurred on the day of consultation (12UTC) with temperature, relative humidity, and atmospheric pressure, as well as 2 days previous to the HTCI. The sensation of cold was associated with about 55% of the days of the period at 12UTC: considering only the peaks of consultations, this association exceeds 90% of days. The highest frequencies of respiratory complications (June, July, and August) were associated with negative temperature anomalies, wind speed and direction, and positive anomalies in relative humidity and atmospheric pressure. Nearly half (45%) of the air masses associated with respiratory complications arrived at Canoas from a SW direction, 19% from the south and 14% from the west. In summary, observed increases in respiratory complications were mainly associated with the presence of cold and humid air (and/or falling temperature with increasing humidity) in the morning.
Hydrogenated fish fat for grazing dairy cows in summer
International Journal of Biometeorology - Tập 45 Số 3 - Trang 111-114 - 2001
M. Gallardo, Silvia Valtorta, Perla Leva, Helena Carla Castro, José Maiztegui
Temperature and rainfall are related to fertility rate after spring artificial insemination in small ruminants
International Journal of Biometeorology - Tập 60 - Trang 1603-1609 - 2016
J. A. Abecia, F. Arrébola, A. Macías, A. Laviña, O. González-Casquet, F. Benítez, C. Palacios
A total number of 1092 artificial inseminations (AIs) performed from March to May were documented over four consecutive years on 10 Payoya goat farms (36° N) and 19,392 AIs on 102 Rasa Aragonesa sheep farms (41° N) over 10 years. Mean, maximum, and minimum ambient temperatures, mean relative humidity, mean solar radiation, and total rainfall on each insemination day were recorded. Overall, fertility rates were 58 % in goats and 45 % in sheep. The fertility rates of the highest and lowest deciles of each of the meteorological variables indicated that temperature and rainfall had a significant effect on fertility in goats. Specifically, inseminations that were performed when mean (68 %), maximum (68 %), and minimum (66 %) temperatures were in the highest decile, and rainfall was in the lowest decile (59 %), had a significantly (P < 0.0001) higher proportion of does that became pregnant than did the ewes in the lowest decile (56, 54, 58, and 49 %, respectively). In sheep, the fertility rates of the highest decile of mean (62 %), maximum (62 %), and minimum (52 %) temperature, RH (52 %), THI (53 %), and rainfall (45 %) were significantly higher (P < 0.0001) than were the fertility rates among ewes in the lowest decile (46, 45, 45, 45, 46, and 43 %, respectively). In conclusion, weather was related to fertility in small ruminants after AI in spring. It remains to be determined whether scheduling the dates of insemination based on forecasted temperatures can improve the success of AI in goats and sheep.
Microclimate and thermal perception in courtyards located in a tropical savannah climate
International Journal of Biometeorology - - 2022
Ivan Júlio Apolônio Callejas, Eduardo Leite Krüger
Fan cooling of the resting area in a free stalls dairy barn
International Journal of Biometeorology - Tập 58 - Trang 1225-1236 - 2013
Ferdinando Calegari, Luigi Calamari, Ermes Frazzi
This summer study evaluated the effect of providing additional fans (cooling) in the resting area within a free-stall dairy barn that had fans and sprinklers in the feeding area and paddock availability. Thirty cows were divided into two homogenous groups and kept in two pens: one had the resting area equipped with two fans (FAN) while no fans were added to the other resting area (CON). Microclimatic parameters, rectal temperature (RT), breathing rate (BR), milk yield, and milk pH traits were recorded. Time budgeting and the behaviour of the cows (time spent in the feeding area, standing and lying in other areas) were also recorded using digital video technology. Two slight-to-moderate heat waves were observed. During the hottest period the daily maximum temperature recorded was 33.5 °C and the daily maximum THI was 81.6. During this period, the BR and RT increased only slightly in both groups, with lower BR (n.s.) in FAN compared with CON. Milk yield was better maintained (n.s.) in FAN compared with CON during the hottest period. The FAN cows showed a greater (P < 0.05) lying time in the free stalls (9.5 and 8.6 h/day in FAN and CON, respectively), whereas CON cows made greater (P < 0.05) use of the paddock during evening and late evening hours. Consequently, the total daily lying time was 13.5 h/day in both groups. In conclusion, the results suggest that using fans in the resting area improves cow comfort, which increases use of the resting area. The lying time results also suggest that the benefits of providing ventilation in the resting area might be more evident in barns where there is no paddock.
Effect of wind speed variation on rainfed wheat production evaluated by the CERES-Wheat model
International Journal of Biometeorology - Tập 66 - Trang 225-233 - 2021
Alireza Araghi, Mohsen Maghrebi, Jørgen Eivind Olesen
Climate is one of the major factors affecting crop phenology and yield. In most previous studies, impacts of temperature (T) and rainfall (R) on crop development, growth, and yield were investigated, while the effect of wind speed (WS) has so far not been assessed. In this study, the influence of WS alteration on rainfed wheat production was evaluated in arid and semi-arid environments during a 25-year period in northeast Iran. In so doing, various climatic scenarios were defined using T, R, and WS changes, and then applied to the CERES-Wheat model included in DSSAT v4.7.5. The results showed that WS variation can alter total ET (planting to harvest) from −12.1 to +8.9%, aboveground biomass from −8.4 to +11.0%, water use efficiency from −13.4 to +19.7%, and grain yield from −11.2 to +15.3%. These changes were in many cases related to the climatic conditions. It was also revealed that in a greater amount of rainfall and shorter growing season (i.e., less drought stress), the WS variation had the stronger impact on total ET; while for aboveground biomass, water use efficiency, and grain yield, the greatest effect of WS variation was detected under the water scarcity conditions (i.e., low rainfall). The results demonstrate that wind speed needs to be better considered in climate change impact studies, in particular in water-scarce regions.
Convective heat transfer from a nude body under calm conditions: assessment of the effects of walking with a thermal manikin
International Journal of Biometeorology - Tập 56 - Trang 319-332 - 2011
A. Virgílio M. Oliveira, Adélio R. Gaspar, Sara C. Francisco, Divo A. Quintela
The present experimental work is dedicated to the analysis of the effect of walking on the thermal insulation of the air layer (I a ) and on the convective heat transfer coefficients (h conv ) of the human body. Beyond the standing static posture, three step rates were considered: 20, 30 and 45 steps/min. This corresponds to walking speeds of approximately 0.23, 0.34 and 0.51 m/s, respectively. The experiments took place in a climate chamber with an articulated thermal manikin with 16 independent parts. The indoor environment was controlled through the inner wall temperatures since the objective of the tests was restricted to the influence of the walking movements under calm conditions. Five set points were selected: 10, 15, 20, 25 and 30°C, and the operative temperature within the test chamber varied between 11.9 and 29.6°C. The highest and lowest I a values obtained were equal to 0.87 and 0.71 clo, respectively, and the reduction in insulation due to walking ranged between 9.8 and 11.5%. The convective coefficients (h conv ) for the whole body and for the different body segments were also determined for each step rate. In the case of the whole body, for the standing static reference posture, the mean value of h conv was equal to 3.3 W/m2°C and a correlation [Nu = Nu(Gr)] for natural convection is also presented in good agreement with previous results. For the other postures, the values of h conv were equal to 3.7, 3.9 and 4.2 W/m2°C, respectively for 20, 30 and 45 steps/min.
Effects of isotonic and isometric exercises with mist sauna bathing on cardiovascular, thermoregulatory, and metabolic functions
International Journal of Biometeorology - Tập 58 - Trang 1109-1117 - 2013
Satoshi Iwase, Yuko Kawahara, Naoki Nishimura, Rumiko Nishimura, Junichi Sugenoya, Chihiro Miwa, Masumi Takada
To clarify the effects of isometric and isotonic exercise during mist sauna bathing on the cardiovascular function, thermoregulatory function, and metabolism, six healthy young men (22 ± 1 years old, height 173 ± 4 cm, weight 65.0 ± 5.0 kg) were exposed to a mist sauna for 10 min at a temperature of 40 °C, and relative humidity of 100 % while performing or not performing ∼30 W of isometric or isotonic exercise. The effect of the exercise was assessed by measuring tympanic temperature, heart rate, systolic and diastolic blood pressure, chest sweat rate, chest skin blood flow, and plasma catecholamine and cortisol, glucose, lactate, and free fatty acid levels. Repeated measures ANOVA showed no significant differences in blood pressure, skin blood flow, sweat rate, and total amount of sweating. Tympanic temperature increased more during isotonic exercise, and heart rate increase was more marked during isotonic exercise. The changes in lactate indicated that fatigue was not very great during isometric exercise. The glucose level indicated greater energy expenditure during isometric exercise. The free fatty acid and catecholamine levels indicated that isometric exercise did not result in very great energy expenditure and stress, respectively. The results for isotonic exercise of a decrease in lactate level and an increase in plasma free fatty acid level indicated that fatigue and energy expenditure were rather large while the perceived stress was comparatively low. We concluded that isotonic exercise may be a more desirable form of exercise during mist sauna bathing given the changes in glucose and free fatty acid levels.
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