Spatiotemporal variability of sunshine duration and influential climatic factors in mainland China during 1959–2017

The cotton plant (Gossypium spp.) is sensitive to numerous environmental factors. This study was aimed at predicting effects of climatic factors grouped into convenient intervals (in days) on cotton flower and boll production compared with daily observations. Two uniformity field trials using the cotton (G. barbadense L.) cv. Giza 75 were conducted in 1992 and 1993 at the Agricultural Research Center, Giza, Egypt. Randomly chosen plants were used to record daily numbers of flowers and bolls during the reproductive stage (60 days). During this period, daily air temperature, temperature magnitude, evaporation, surface soil temperature, sunshine duration, humidity, and wind speed were recorded. Data, grouped into intervals of 2, 3, 4, 5, 6, and 10 d, were correlated with cotton production variables using regression analysis. Evaporation was found to be the most important climatic variable affecting flower and boll production, followed by humidity and sunshine duration. The least important variables were surface soil temperature at 0600 and minimum air temperature. The 5-d interval was found to provide the best correlation with yield parameters. Applying appropriate cultural practices that minimize the deleterious effects of evaporation and humidity could lead to an important improvement in cotton yield in Egypt. Key words: Cotton, flower production, boll production, boll retention

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Investigating the spatiotemporal variation of fish choruses to help identify important foraging habitat for Indo-Pacific humpback dolphins, Sousa chinensis

ICES Journal of Marine Science ◽

10.1093/icesjms/fsx197 ◽

2017 ◽

Vol 75 (2) ◽

pp. 510-518 ◽

Cited By ~ 10

Author(s):

Matthew K Pine ◽

Ding Wang ◽

Lindsay Porter ◽

Kexiong Wang

Keyword(s):

Hong Kong ◽

Mainland China ◽

Spatiotemporal Variability ◽

Marine Spatial Planning ◽

Separate Species ◽

Mainland Chinese ◽

Predator Prey ◽

Chinese Waters ◽

New Information ◽

Hong Kong Waters

Abstract Given the common physical overlapping between coastal developments and important marine mammal habitats, there is a need to identify potentially important foraging grounds for dolphins when informing marine spatial planning and management of underwater noise. Hydrophones were deployed at four locations either side of the mainland China–Hong Kong Special Administrative Region border to monitor the presence of soniferous fishes; a key prey item for Indo-Pacific humpback dolphins. Five distinct chorus-types were identified; each showing spatiotemporal variability. Each chorus-type was assumed to represent a separate species. Chorus-type diversity also differed between sites, with SP4 and SP5 types only being detected within Hong Kong waters where bottom trawling is illegal. Chorus-type SP1 was only detected at the recording sites in mainland Chinese waters. Call rates and chorus duration were highest during the spring and summer months. Given these dolphins show a predator-prey relationship, these data provide new information on the local fish communities at a much finer-scale than fish landing records and a baseline of fish activity in an environment that is challenging to explore. Overlaid with acoustic detections of foraging dolphins, these data form a basis for identifying potentially important foraging habitats that should be afforded the highest priority for protection.

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Spatiotemporal variability of reference evapotranspiration and its contributing climatic factors in Yunnan Province, SW China, 1961–2004

Climatic Change ◽

10.1007/s10584-012-0479-4 ◽

2012 ◽

Vol 116 (2) ◽

pp. 309-325 ◽

Cited By ~ 75

Author(s):

Ze-Xin Fan ◽

Axel Thomas

Keyword(s):

Yunnan Province ◽

Reference Evapotranspiration ◽

Climatic Factors ◽

Spatiotemporal Variability ◽

Sw China

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Long-term trends in solar radiation and the associated climatic factors over China for 1961-2000

Annales Geophysicae ◽

10.5194/angeo-23-2425-2005 ◽

2005 ◽

Vol 23 (7) ◽

pp. 2425-2432 ◽

Cited By ~ 121

Author(s):

F. Liang ◽

X. A. Xia

Keyword(s):

Solar Radiation ◽

Climatic Factors ◽

Sunshine Duration ◽

Cloud Amount ◽

Atmospheric Composition ◽

Abrupt Decrease ◽

Radiative Processes ◽

Aerosol Loading ◽

Long Term Trends

Abstract. Long-term trends in downwelling solar irradiance and associated climatic factors over China are studied in the paper. Decreasing trends in global and direct radiation are observed over much of China. The largest decrease occurs in South and East China (east of about 100° E and south of about 40° N). The spatial pattern of observed trends in diffuse irradiance is complex and inhomogeneous. An intriguing aspect of trends in global and direct irradiance is the rather abrupt decrease in annual and seasonal mean values from 1978 onward. The decreasing trends in solar radiation in China did not persist into the 1990s. The spatial and temporal patterns of trends in sunshine duration are consistent with that of global and direct irradiance. A decreasing trend in rainy days is observed over much of China, which is in agreement with the secular trend in cloud amount. The fact that trends in cloud amount and solar radiation are quite similar suggests that the cloud amount is not the primary cause for the decrease in solar radiation. Visibility in the eastern part of China has deteriorated heavily as a result of the rapid increase in aerosol loading. The statistical analysis showed that atmospheric transmission under clear conditions decreased rapidly. These facts suggest that the rapid increase in aerosol loading should be one of the principle causes for the decrease in solar radiation. The observed diurnal temperature range decreases remarkably in China, which is closely related to the increase in aerosols. The effects of anthropogenic air pollutants on climate should be further studied and included in the simulation of climate and projection of climate scenario. Keywords. Atmospheric composition and structure (Aerosol and particles; General or miscellaneous) – Meteorology and atmospheric dynamics (Radiative processes)

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Effect of climatic factors on the seasonal fluctuation of human brucellosis in Yulin, Northern China

10.21203/rs.2.12273/v1 ◽

2019 ◽

Author(s):

Kun Liu ◽

Zurong Yang ◽

Weifeng Liang ◽

Tianci Guo ◽

Yong Long ◽

...

Keyword(s):

Climatic Factors ◽

Sunshine Duration ◽

Disease Incidence ◽

Climatic Variability ◽

Northern China ◽

Human Brucellosis ◽

Seasonal Fluctuations ◽

Cross Correlation Analysis ◽

Non Linear ◽

Yulin City

Abstract Background: Brucellosis is a serious public health problem primarily affecting livestock workers. The strong seasonality of the disease indicates that climatic factors may play important roles in the disease transmission. However, the associations between climatic variability and human brucellosis are still poorly understood. Methods: Data for a 14-year series of human brucellosis cases and seven climatic factors were collected in Yulin City from 2005 to 2018, one of the most endemic areas in northern China. Using the cross-correlation analysis, the Granger causality test, and the distributed lag non-linear model (DLNM), we assessed the quantitative relationships and exposure-lag-response effects between monthly climatic factors and human brucellosis. Results: A total of 7,103 cases of human brucellosis were reported from 2005 to 2018 in Yulin City with a distinct peak between April and July. Seasonal fluctuations in the transmission of human brucellosis were significantly affected by temperature, sunshine duration, and evaporation. The effects of climatic factors were non-linear over the 6-month period, and higher values of these factors usually increased disease incidence. The maximum separate relative risk (RR) was 1.36 (95% confidence interval (CI), 1.03–1.81) at a temperature of 17.4 °C, 1.12 (95% CI, 1.03–1.22) with 311 hours of sunshine, and 1.18 (95% CI, 0.94–1.48) with 314 mm of evaporation, respectively. In addition, the effects of these three climatic factors were cumulative, with the highest RR of 2.27 (95% CI, 1.09–4.57), 1.54 (95% CI, 1.10–2.18), and 1.27 (95% CI, 0.73–2.14), respectively. Conclusions: In Yulin, northern China, variations in climatic factors, especially temperature, sunshine duration, and evaporation, contributed significantly to seasonal fluctuations of human brucellosis within 6 months. The key determinants of brucellosis transmission and the identified complex associations are useful references for developing strategies to reduce disease burden.

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Analysis of the Response of Long-Term Vegetation Dynamics to Climate Variability Using the Pruned Exact Linear Time (PELT) Method and Disturbance Lag Model (DLM) Based on Remote Sensing Data: A Case Study in Guangdong Province (China)

Remote Sensing ◽

10.3390/rs13101873 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1873

Author(s):

Sai Wang ◽

Fenglei Fan

Keyword(s):

Relative Humidity ◽

Surface Runoff ◽

Climatic Factors ◽

Linear Time ◽

Sunshine Duration ◽

Time Lag ◽

Vegetation Coverage ◽

Lag Model ◽

Vegetation Activities

The dynamic change and spatial–temporal distribution of vegetation coverage are of great significance for regional ecological evolution, especially in the subtropics and tropics. Identifying the heterogeneity in vegetation activities and its response to climate factors is crucial for projecting ecosystem dynamics. We used long-term (2001–2018) satellite-derived enhanced vegetation index (EVI) datasets and climatic factors to analyze the spatiotemporal patterns of vegetation activities in an experimental area in Guangdong Province (China), as well as their links to changes in temperature (TEM), relative humidity (HUM), precipitation (PRE), sunshine duration (SUN), and surface runoff. The pruned exact linear time change point detection method (PELT) and the disturbance lag model (DLM) were used to understand the detailed ecological coverage status and time lag relationships between the EVI and climatic factors. The results indicate the following. (1) At the whole regional scale, a significant overall upward trend in the EVI variation was observed in 2001–2018. More specifically, there were two distinct periods with different trends, which were split by a turning point in 2005. PRE was the main climate-related driver of the rising EVI pre-2005, and the increase in TEM was the main climate factor influencing the forest EVI variation post-2006. (2) A three-month time lag effect was observed in the EVI response to relative humidity. The same phenomenon was found in the sunshine duration factor. (3) The EVI of farmlands (one type of land use) exhibited the largest lags between relative humidity and the sunshine duration factor, followed by grasslands and forests. (4) The comprehensive index of surface runoff could explain the time lags of vegetation activities, and the surface runoff value showed an apparently negative relationship with the vegetation coverage change.

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Spatiotemporal Variations of Reference Evapotranspiration and Its Determining Climatic Factors in the Taihang Mountains, China

Water ◽

10.3390/w13213145 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3145

Author(s):

Tingting Kang ◽

Zeng Li ◽

Yanchun Gao

Keyword(s):

Climate Change ◽

Land Surface ◽

Reference Evapotranspiration ◽

Climatic Factors ◽

Sunshine Duration ◽

High Elevation ◽

Lower Sensitivity ◽

Effective Measure ◽

The Impact ◽

The Relationship

Reference evapotranspiration (ETo) is an effective measure of atmospheric water demand of the land surface. In-depth investigations of the relationship between ETo and primary climatic factors can facilitate the adaptable agriculture and optimize water management, especially in the ecologically fragile Taihang Mountains (THM). This work assessed the spatiotemporal dynamics of ETo and its driving climatic factors from 1973 to 2016 in THM. Results showed: (1) Annual ETo slightly increased during 1973–2016; relative humidity (RH) decreased more slowly, the temperature increased more rapidly, and wind speed (WS) decreased more rapidly at higher elevation than those at lower elevations; (2) two breakpoints occurred in ETo series at 1990 and 1997, and an “evaporation paradox” existed in 1973–1990; (3) ETo at higher elevations had greater sensitivity to changes in RH and lower sensitivity to changes in Tmax and WS. Sensitivity of ETo to minimum air temperature (Tmin) at middle elevations was lowest among three elevation bands; (4) RH and sunshine duration (SD) were the dominant climatic factors of ETo for most periods and stations. This study helps us understand the impact of climate change on ETo in mountainous areas and confirms reference evapotranspiration in high-elevation areas is particularly sensitive to climate change.

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The transmission of Hand, Foot, and Mouth Disease in East and Southeast Asia

10.1101/612580 ◽

2019 ◽

Cited By ~ 1

Author(s):

Jijun Zhao ◽

Yanfen Wang

Keyword(s):

Southeast Asia ◽

Climatic Factors ◽

Transmission Rate ◽

Mainland China ◽

Foot And Mouth Disease ◽

Contact Rate ◽

Foot And Mouth ◽

Hong Kong Sar ◽

East And Southeast Asia ◽

Macau Sar

AbstractHand Foot and Mouth Disease (HFMD) is in endemic in many countries in East and Southeast Asia, including those in the tropical or subtropical climate zones. To substantially reduce HFMD, it is necessary to design effective control measures, which is based on a deep understanding of the disease transmission. However, the transmission mechanism of HFMD was rarely studied. The cyclic pattern of HFMD incidence is believed to be related to climatic factors, rather than school terms as observed from childhood infectious diseases in developed countries in the prevaccination era. Furthermore, the association of incidence and climatic factors in different locales in China are inconsistent and even contradictory. Here we selected countries or regions in typical climatic zones in East and Southeast Asia to study the transmission rate and its seasonality for HFMD. Countries or regions selected representing temperate, subtropical and tropical zones are Japan, Hong Kong SAR, Macau SAR and Singapore. Comparatively, we chose provinces in mainland China in three climate zones and contrast them with above selected regions or countries. We used Time Series Susceptible Infected Recovered (TSIR) model to estimate the HFMD transmission rate. The parameters in the TSIR model were estimated by Markov Chain Monte Carlo (MCMC). We then used a linear regression model to analyze the effects of climate factors, seasonal contact rate in children (and seasonal contact rate in population for provinces in China) on the transmission rate of HFMD in selected regions. We found that: 1) transmission rate of HFMD is highly seasonal in the studied countries, SARs and provinces of mainland China, except Singapore; 2) the HFMD transmission rate can be affected by the climatic factors as well as the seasonal contact rate of population, depending on which factor is dominant; 3) The transmission rate in provinces in China increased dramatically during the time period of Chinese Spring Travel Rush that has higher population contact; 4) transmission rate seasonality in Japan, Hong Kong SAR and Macau SAR is affected by climatic factors.Author SummaryHand, Foot and Mouth Disease (HFME) is endemic in East and Southeast Asia with reported cases of more than two million every year. The epidemic patterns such as annual cyclic pattern of reported HFMD cases have been observed and studied for the purpose of understanding the disease. The mechanisms that describe how a disease is transmitted cannot be observed, however they lead to the observed epidemic patterns of the disease. We analyzed the transmission rate (that help to understand the transmission mechanism) of HFMD in selected countries or regions that represent territories in tropical, subtropical and temperate climatic zones in East and Southeast Asia and compared the HFMD transmission in these regions. We also analyzed the possible driving factors of the seasonal transmission of HFMD. The transmission of HFMD can be affected by both social behavior and climatic factors, however either of them can dominant the effect on HFMD transmission depending on regions or countries. In mainland China, high population contact rate is the dominant factor to have high HFMD transmission; while in Japan, Hong Kong SAR and Macau SAR, climatic factors have the dominant effect. These findings can help design effective control measures.

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Sunshine duration climatology and trends in association with other climatic factors over India for 1970-2006

MAUSAM ◽

10.54302/mausam.v60i4.1113 ◽

2021 ◽

Vol 60 (4) ◽

pp. 437-454

Author(s):

A. K. JASWAL

Keyword(s):

Climatic Factors ◽

Sunshine Duration ◽

Cloud Amount ◽

Total Cloud Amount ◽

Gangetic Plains ◽

Post Monsoon ◽

Sunshine Hours ◽

Maximum Decrease ◽

Rainy Days ◽

Good Visibility

Changes in sunshine duration in association with total cloud amount, rainy days and good visibility days over India were examined for 1970-2006. Climatologically, annual total sunshine duration over west Rajasthan and adjoining Gujarat is more than 3100 hours which is ideal for harnessing solar energy over these regions. The trend analysis indicates significant decrease in sunshine duration over the country for all months (except June) and the maximum decrease has taken place in January (-0.44 hour/decade) followed by December (-0.39 hour/decade). Seasonally, decline in sunshine hours is highest in winter and post monsoon (4% per decade) and lowest in monsoon (3% per decade). Decadal variations indicate maximum decrease in sunshine over the Indo-Gangetic plains and south peninsula during 1990-1999. Spatially, the decreasing trends in sunshine hours are highest in Indo-Gangetic plains and south peninsula while regions over Rajasthan and Gujarat have lowest decrease. Out of 40 stations under study, the maximum decrease in sunshine has occurred at New Delhi (winter at 13% per decade and post monsoon at 10% per decade) and Varanasi (summer and monsoon at 7% per decade). Correlation analysis of sunshine duration with total cloud amount, rainy days and good visibility days indicates regional and seasonal variations in factors explaining the long term trends in sunshine duration over the country.

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Impacts of Indian Ocean Dipole–Like SST on Rice Yield Anomalies in Jiangsu Province

Frontiers in Earth Science ◽

10.3389/feart.2020.568365 ◽

2021 ◽

Vol 8 ◽

Author(s):

Jingwei Xu ◽

Nikolay V. Koldunov ◽

Min Xu ◽

Xiuhua Zhu ◽

Klaus Fraedrich ◽

...

Keyword(s):

Water Vapor ◽

Indian Ocean ◽

Bay Of Bengal ◽

Indian Ocean Dipole ◽

Rice Yield ◽

Climatic Factors ◽

Sunshine Duration ◽

Eastern China ◽

Jiangsu Province ◽

Significance Level

One of the main water vapor sources of eastern China is the Bay of Bengal, over which the circulation is influenced by the Tropical Indian Ocean Dipole (TIOD). The TIOD has a long-lasting effect on weather patterns, which in turn influence the rice yield and quality in eastern China, such as in Jiangsu Province. To identify the main mechanism involved, we perform a detailed investigation of the connections between the TIOD-like sea surface temperature (SST) and the climatic suitability for growing rice, and the subsequent rice yield anomalies, in Jiangsu Province. In particular, we compare the relationships, and identify the underlying mechanisms, of TIOD SST with suitable sunshine duration, temperature and precipitation during the period of rice culture in the province. Singular Value Decomposition (SVD) results show that the TIOD-like SST has a close correlation with the rice yield anomalies, with a temporal correlation coefficient of 0.43 for 53 years, passing the 99% significance level. Furthermore, in the negative TIOD-like SST years, the background circulation weakens the transport effect of the atmospheric river through which water vapor is transported from the Bay of Bengal to eastern China. This decreased amount of transported water vapor decreases the precipitation and total cloud cover in the province. In turn, this significantly increases the sunshine duration, which plays a key role in rice yield anomalies. The increased sunshine duration and higher temperatures lead to positive rice yield anomalies, and vice versa. Our findings highlight that climatic factors, such as TIOD-like SST, have a far-reaching influence on agricultural production (in this case, rice yield), and thus special attention should be paid to interdisciplinary research in the fields of climate and agriculture.

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