Proportion and distribution of rain and snow in China from 1960 to 2018

2021 ◽  
Keyword(s):  
Atmospheric Pressure ◽  
Annual Precipitation ◽  
Annual Rainfall ◽  
Annual Number ◽  
Upward Trend ◽  
Total Annual Precipitation ◽  
Change Dynamics ◽  
Different Types ◽  
Northwestern Region ◽  
Average Annual Number

Abstract Rainfall and snowfall have different effects on energy balance calculations and land-air interactions in terrestrial models. The identification of precipitation types is crucial to understand climate change dynamics and the utilization of water resources. However, information regarding precipitation types is not generally available. The precipitation obtained from meteorological stations across China recorded types only before 1979. This study parameterized precipitation types with air temperature, relative humidity and atmospheric pressure from 1960 to 1979, and then identified precipitation types after 1980. Results show that the main type of precipitation in China was rainfall, and the average annual rainfall days (amounts) across China accounted for 83.08% (92.55%) of the total annual precipitation days (amounts). The average annual snowfall days (amounts) in the northwestern region accounted for 32.27% (19.31%) of the total annual precipitation days (amounts), which is considerably higher than the national average. The average annual number of rainfall and snowfall days both displayed a downward trend while the average annual amounts of these two precipitation types showed an upward trend, but without significance at 0.1 levels. The annual number of rainfall and snowfall days in the southwestern region decreased significantly (-2.27 d/decade and -0.31 d/decade, p < 0.01). The annual rainfall amounts in the Jianghuai region increased significantly (40.70 mm/decade, p < 0.01), and the areas with the most significant increase in snowfall amounts were the northwestern (3.64 mm/decade, p < 0.01). These results can inform our understanding of the distribution and variation of precipitation with different types in China.

scholarly journals Village-level climate and weather variability, mediated by village-level crop yield, is associated with linear growth in children in Uganda

2020 ◽  
Vol 5 (10) ◽  
pp. e002696
Author(s):  
Paddy Ssentongo ◽  
Djibril M Ba ◽  
Claudio Fronterre ◽  
Vernon M Chinchilli
Keyword(s):  
Crop Yield ◽  
Aridity Index ◽  
Precipitation Anomaly ◽  
Annual Precipitation ◽  
Annual Rainfall ◽  
Total Annual Precipitation ◽  
Mediating Role ◽  
Village Level ◽  
Z Scores ◽  
Height For Age

IntroductionTo investigate total annual precipitation, precipitation anomaly and aridity index in relation to linear growth in children under 5 in Uganda and quantify the mediating role of crop yield.MethodsWe analysed data of 5219 children under 5 years of age who participated in the 2016 Uganda Demographic and Health Survey. Annual crop yield in kilograms per hectare for 42 crops at a 0.1° (~10 km at the equator) spatial resolution square grid was obtained from the International Food Policy Research Institute. Normalised rainfall anomaly and total precipitation were derived from the African Rainfall Estimation Algorithm Version 2 product. Linear regression models were used to associate total annual precipitation and anomalies with height-for-age z-scores and to explore the mediating role of crop yield qualitatively. The intervening effects were quantitatively estimated by causal mediation models.ResultsTwenty-nine per cent of children were stunted (95% CI 28% to 31%). After adjusting for major covariates, higher total annual precipitation was significantly associated with increasing height-for-age z-scores. At the mean, an increase of 1 standard deviation in local annual rainfall was associated with a 0.07-point higher z-score. Aridity index and precipitation anomaly were not associated with height-for-age z scores in altitude-adjusted models. Crop yields of nuts, seeds, cereals and pulses were significant mediating factors. For instance, 38% of the association between total annual precipitation with height-for-age z-scores can be attributed to the yield of sesame seeds.ConclusionsHigher total annual precipitation at the village-level was significantly associated with higher height-for-age z-scores among children in Uganda. This association can be partially explained by higher crop yield, especially from seeds and nuts. This study suggests that more attention should be paid to villages with lower annual rainfall amounts to improve water availability for agriculture.

scholarly journals Changes in Slight and Extreme Precipitation Events From 1963 to 2017 Over Northern Xinjiang, China

2021 ◽  
Vol 9 ◽  
Author(s):  
Minggang Li ◽  
Yong Zhao ◽  
Yang Li ◽  
Xin Zhou ◽  
Shaobo Zhang
Keyword(s):  
Extreme Precipitation ◽  
Precipitation Amount ◽  
Annual Precipitation ◽  
Annual Number ◽  
Total Annual Precipitation ◽  
Northern Xinjiang ◽  
Extreme Precipitation Events ◽  
Annual Precipitation Amount ◽  
Mean Temperature ◽  
Different Temperatures

Based on daily measured data from 25 stations in Xinjiang Province from 1963 to 2017, we discuss the statistical characteristics, linear trends, and temporal concentration of slight precipitation (SP) and extreme precipitation (EP) events, and consider relationships between SP and EP events and daily mean temperature. The results show that SP events contribute strongly to the total annual number of wet days, and that EP events contribute strongly to the total annual precipitation amount. In consist with the decrease in SP events and the increase in EP events over the 55-year period, the contribution of SP events to total annual number of wet days has decreased significantly while the contribution of EP events to total annual precipitation amount has increased significantly. SP event usually distributes through most months of the year, whereas EP event usually concentrates in summer (JJA). Influenced by the negative trends for SP events frequency and positive trends of EP events frequency during recent decades, the concentration degree for SP and EP events have significantly increased and decreased, respectively. Distinct differences are found between the relationships of SP events and EP events to daily mean temperature. The daily mean temperature recorded at the stations in Northern Xinjiang on days with SP events was between –35°C and +34°C, and for EP events ranged from –21°C to +30°C. Regionally averaged curves for the change in SP and EP event frequency with temperature have bimodal and unimodal distributions, respectively. Trends for daily mean temperatures and for the frequency of SP events at different temperatures agree well over nearly the entire temperature range, while trends for daily mean temperatures and for the frequency of EP events at different temperatures are not always consistent. These results will help to improve our understanding of the characteristics and variability of precipitation in arid regions within the context of climate warming.

The prevention of tetanus - the use of Human Antitetanus Immunoglobulin

1975 ◽  
Vol 13 (20) ◽  
pp. 77-79
Keyword(s):  
Rare Disease ◽  
Annual Number ◽  
True Incidence ◽  
Average Annual Number

Tetanus is a preventable though rare disease. In Britain, its incidence is steadily diminishing.1 The average annual number of deaths from tetanus over the period 1960–70 was 17 compared with 45 in the period 1950–60. The disease has been notifiable since October 1968 but the number of notifications returned annually does not represent the true incidence.

scholarly journals Enzyme-catalyzed reactions in different types of high-pressure enzymatic reactors

2006 ◽  
Vol 12 (3) ◽  
pp. 159-163
Author(s):  
Mateja Primozic ◽  
Maja Habulin ◽  
Muzafera Paljevac ◽  
Zeljko Knez
Keyword(s):  
High Pressure ◽  
Atmospheric Pressure ◽  
Ceramic Membranes ◽  
Stirred Tank ◽  
Optimal Temperature ◽  
Stirred Tank Reactor ◽  
Tank Reactor ◽  
Humicola Insolens ◽  
Different Types ◽  
Hydrolysis Of

The enzyme-catalyzed hydrolysis of carboxy-methyl cellulose (CMC) was performed in three different types of reactors; in a batch stirred-tank reactor (BSTR) operating at atmospheric pressure, in a high-pressure batch stirred-tank reactor (HP BSTR) and in a high-pressure continuous tubular-membrane reactor (HP CTMR). In the high-pressure reactors aqueous SC CO2 was used as the reaction medium. The aim of our research was optimization of the reaction parameters for reaction performance. All the reactions were catalyzed by cellulase from Humicola insolens. Glucose production in the high-pressure batch stirred-tank reactor was faster than in the BSTR at atmospheric pressure. The optimal temperature for the reaction performed in the BSTR at atmospheric pressure was 30?C, while the optimal temperature for the reaction performed in SC CO2 was 32?C. The influence of the application of tubular ceramic membranes in the high-pressure reaction system was studied on the model reaction of CMC hydrolysis at atmospheric pressure and in SC CO2. The reaction was catalyzed by cellulase from Humicola insolens covalently linked to the surface of the ceramic membrane. The hydrolysis of CMC in SC CO2 and at atmospheric pressure was performed for a long time period. The reaction carried out in SC CO2 was more productive than the reaction performed at atmospheric pressure.

scholarly journals Analysis of Daily Rainfall and Spatiotemporal Trends of Extreme Rainfall at Paraná Slope of the Itararé Watershed, Brazil

2020 ◽  
Vol 35 (2) ◽  
pp. 357-374
Author(s):  
Paulo Miguel de Bodas Terassi ◽  
José Francisco de Oliveira Júnior ◽  
Givanildo de Gois ◽  
Bruno Serafini Sobral ◽  
Emerson Galvani ◽  
...  
Keyword(s):  
Daily Rainfall ◽  
Extreme Rainfall ◽  
High Volume ◽  
Annual Rainfall ◽  
Annual Number ◽  
Subtropical Climate ◽  
Homogeneous Groups ◽  
The North ◽  
Spatiotemporal Trends ◽  
Mk Test

Abstract The knowledge of intensity and frequency of rainfall allows establishing predictive measures to minimize impacts caused by high volume of rainfall totals in a region. Therefore, the objective is to evaluate daily rainfall for Paraná slope of the Itararé watershed (PSIW) and to verify the spatiotemporal trend of intense and extreme daily rainfall. Rainfall data from 14 stations collected from 1976 to 2012 were used with less than 4% of data faults. Multivariate analysis based on cluster analysis technique (CA) was used applying the Euclidean distance for the identification of homogeneous groups, and the quantiles technique to classify daily rainfall. The Mann-Kendall (MK) test was used to identify trends for annual rainfall totals, annual number of rainy days (ANRD) and for the occurrence of intense (R95p) and extreme (R99p) rainfall. The CA technique identified three rainfall groups (HG I, II and III). Given the latitudinal position of the area, rainfall at the southern sector is characterized by its greater similarities with the subtropical climate, whereas in the North sector there is a consistent reduction of rainfall totals in autumn and, especially, during winter months, which are characteristic of the tropical climate. The MK test identified the downward trend of ANRD, with greater significance for the south-centered sectors of the basin. The observed trends for the intense (R95p) and extreme (R99p) daily rainfall show the predominance of reduction for the Southwest and central sector, followed by a significant increase in the Southeast and North sectors of the PSIW.

scholarly journals IMPACT OF CLIMATE CHANGE ON THE HYDRAULIC MODES OF OPERATION OF SURFACE RUNOFF DRAINAGE SYSTEMS

2020 ◽  
Vol 25 (4) ◽  
pp. 50-57
Author(s):  
V. S. Ignatchik ◽  
◽  
S. Y. Ignatchik ◽  
N. V. Kuznetsova ◽  
A. Y. Fes’kova ◽  
...  
Keyword(s):  
Climate Change ◽  
Linear Approximation ◽  
Surface Runoff ◽  
Annual Precipitation ◽  
Climatic Parameters ◽  
Modes Of Operation ◽  
Total Annual Precipitation ◽  
Rain Gauges ◽  
Drainage Networks ◽  
The Government

Introduction. Based on Resolution of the Government of the Russian Federation No. 782 “On water supply and wastewater disposal plans”, the volume of generated wastewater should be forecast for a period of at least 10 years. Along with this, it is also necessary to assess the hydraulic modes of operation of networks and collectors, specified earlier. However, the existing regulatory literature lacks data on the dynamics of calculated rain intensities and their prospective values. The analysis of the subject area showed that it is possible to determine the climatic parameters of an area, and thus establish the values for the characteristics of calculated rain, based on the data of long-term observations (from 20 years) with one self-recording rain gauge, or with a network of similar rain gauges, with a duration of observations of 5 years or more. A similar network of rain gauges is available in St. Petersburg. It makes it possible to assess the actual values of climatic parameters, but due to the lack of statistical data does not allow for assessing the dynamics of their changes. Therefore, the purpose of this article is to roughly estimate the dynamics of changes in climatic parameters in St. Petersburg and the degree of their impact on the hydraulic modes of operation of surface runoff drainage networks and collectors. Methods. In the course of the study, we analyzed the dynamics of changes in the total annual precipitation H and rain force in St. Petersburg and examined the influence of the dynamics of rain force changes on the operation of surface runoff drainage networks and collectors. Results. At the first stage of the study, we obtained the results of linear approximation of the H data, the calculated values of rain force changes Δ, and the results of linear approximation of the Δ data. The second stage of the study resulted in changes in the hydraulic modes of runoff input during the design period and in 50 years. Conclusion. We experimentally substantiated the possibility to determine the dynamics of rain force changes (at P = 0.33 and with acceptable accuracy) depending on the dynamics of changes in the total annual precipitation. For networks designed and laid 50 years ago, the actual rain force changes will be 9 %. As a result of climate change, water consumption in the calculation periods increased by about 26% with an increase in the total volume of discharged water by 9–10 %.

scholarly journals Effects of record length and resolution on the derived distribution of annual precipitation

2015 ◽  
Vol 12 (12) ◽  
pp. 12987-13018
Author(s):  
C. I. Meier ◽  
J. S. Moraga ◽  
G. Pranzini ◽  
P. Molnar
Keyword(s):  
High Resolution ◽  
Interannual Variability ◽  
Probability Model ◽  
Annual Precipitation ◽  
Annual Rainfall ◽  
Precipitation Data ◽  
Return Periods ◽  
Record Length ◽  
High Return ◽  
Log Normal

Abstract. Traditional frequency analysis of annual precipitation requires the fitting of a probability model to yearly precipitation totals. There are three potential problems with this approach: a long record (at least 25 ~ 30 years) is required in order to fit the model, years with missing data cannot be used, and the data need to be homogeneous. To overcome these limitations, we test an alternative methodology proposed by Eagleson (1978), based on the derived distribution approach (DDA). This allows for better estimation of the probability density function (pdf) of annual rainfall without requiring long records, provided that high-resolution precipitation data are available to derive external storm properties. The DDA combines marginal pdfs for storm depth and inter-arrival time to arrive at an analytical formulation of the distribution of annual precipitation under the assumption of independence between events. We tested the DDA at two temperate locations in different climates (Concepción, Chile, and Lugano, Switzerland), quantifying the effects of record length. Our results show that, as compared to the fitting of a normal or log-normal distribution, the DDA significantly reduces the uncertainty in annual precipitation estimates (especially interannual variability) when only short records are available. The DDA also reduces the bias in annual precipitation quantiles with high return periods. We also show that using precipitation data aggregated every 24 h, as commonly available at most weather stations, introduces a noticeable bias in the DDA. Our results point to the tangible benefits of installing high-resolution (hourly or less) precipitation gauges at previously ungauged locations. We show that the DDA, in combination with high resolution gauging, provides more accurate and less uncertain estimates of long-term precipitation statistics such as interannual variability and quantiles of annual precipitation with high return periods even for records as short as 5 years.

scholarly journals Variability and Trends of Temperature and Rainfall Over Three Agro-Ecological Zones in North Shewa, Central Ethiopia

2020 ◽  
Author(s):  
Ashenafi Hailu Shekuru ◽  
Arega Bazezew Berlie ◽  
Yechale Kebede Bizuneh
Keyword(s):  
Crop Production ◽  
Smallholder Farmers ◽  
Annual Rainfall ◽  
Maximum Temperature ◽  
Upward Trend ◽  
Central Ethiopia ◽  
Ecological Zones ◽  
Annual Minimum Temperature ◽  
Rainfall Anomalies ◽  
Agro Ecological Zones

Abstract This study aims to analyze variability and trends of temperature and rainfall over three agro-ecological zones (AEZs) in Central Ethiopia. Gridded rainfall and temperature data, recorded on daily basis for 35 years (1979 - 2013) at 30 meteorological stations, were used for analysis. While Mann–Kendall test was applied to analyze the trends in rainfall and temperature, Sen’s slope estimator was used to determine the magnitude of change. The study detected an upward trend of 0.07°C/annum (p < 0.001) in mean annual maximum temperature at Kolla AEZ. It also showed an upward trend of 0.06/year (p < 0.001) for both Dega and Woina Dega AEZs. Mean annual minimum temperature exhibited an upward trend of 0.03°C/year at Kolla (p < 0.001), Woina Dega (p < 0.05), and Dega (p < 0.01), signifying a 1.05°C increase between 1979 and 2013. Results from precipitation concentration index (PCI) revealed highest percentage (97.1%) of irregular distributions in annual rainfall pattern at Kolla AEZ, followed by Woina Dega (82.9%). Standardized rainfall anomalies (SRA) computed in the study also showed higher percentage (28.6%) of drought in Kolla AEZ, which experienced drought once in every 3 or 4 years. The study revealed negative annual rainfall anomalies for 18 years in Kolla and 16 years in both Dega and Woina Dega AEZs. The reduced precipitation and rise in temperature could trigger wide-ranging influences on agricultural practices and crop production of smallholder farmers. Policymakers and stakeholders should give priority in designing and introducing pro-poor plus geographically differentiated adaptive strategies.

scholarly journals A Multiregion Model Evaluation and Attribution Study of Historical Changes in the Area Affected by Temperature and Precipitation Extremes

2016 ◽  
Vol 29 (23) ◽  
pp. 8285-8299 ◽  
Author(s):  
Andrea J. Dittus ◽  
David J. Karoly ◽  
Sophie C. Lewis ◽  
Lisa V. Alexander ◽  
Markus G. Donat
Keyword(s):  
North America ◽  
Northern Hemisphere ◽  
Minimum Temperature ◽  
Climate Models ◽  
Heavy Precipitation ◽  
Precipitation Extremes ◽  
Annual Precipitation ◽  
Total Annual Precipitation ◽  
Temperature And Precipitation ◽  
Increasing Trends

Abstract The skill of eight climate models in simulating the variability and trends in the observed areal extent of daily temperature and precipitation extremes is evaluated across five large-scale regions, using the climate extremes index (CEI) framework. Focusing on Europe, North America, Asia, Australia, and the Northern Hemisphere, results show that overall the models are generally able to simulate the decadal variability and trends of the observed temperature and precipitation components over the period 1951–2005. Climate models are able to reproduce observed increasing trends in the area experiencing warm maximum and minimum temperature extremes, as well as, to a lesser extent, increasing trends in the areas experiencing an extreme contribution of heavy precipitation to total annual precipitation for the Northern Hemisphere regions. Using simulations performed under different radiative forcing scenarios, the causes of simulated and observed trends are investigated. A clear anthropogenic signal is found in the trends in the maximum and minimum temperature components for all regions. In North America, a strong anthropogenically forced trend in the maximum temperature component is simulated despite no significant trend in the gridded observations, although a trend is detected in a reanalysis product. A distinct anthropogenic influence is also found for trends in the area affected by a much-above-average contribution of heavy precipitation to annual precipitation totals for Europe in a majority of models and to varying degrees in other Northern Hemisphere regions. However, observed trends in the area experiencing extreme total annual precipitation and extreme number of wet and dry days are not reproduced by climate models under any forcing scenario.

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