Contrasts between the Interannual Variations of Extreme Rainfall over Western and Eastern Sichuan in Mid-summer

2022 ◽  
Author(s):  
Mengyu Deng ◽  
Riyu Lu ◽  
Chaofan Li
Keyword(s):  
Extreme Rainfall ◽  
Interannual Variations ◽  
Eastern Sichuan

scholarly journals On the ability of a global atmospheric inversion to constrain variations of CO<sub>2</sub> fluxes over Amazonia

2015 ◽  
Vol 15 (2) ◽  
pp. 1915-1952
Author(s):  
L. Molina ◽  
G. Broquet ◽  
P. Imbach ◽  
F. Chevallier ◽  
B. Poulter ◽  
...  
Keyword(s):  
South America ◽  
Amazon Basin ◽  
Transport Model ◽  
Net Ecosystem Exchange ◽  
Extreme Rainfall ◽  
Atmospheric Composition ◽  
Interannual Variations ◽  
The Impact ◽  
Seasonal And Interannual Variations ◽  
Atmospheric Inversion

Abstract. The exchanges of carbon, water, and energy between the atmosphere and the Amazon Basin have global implications for current and future climate. Here, the global atmospheric inversion system of the Monitoring of Atmospheric Composition and Climate service (MACC) was used to further study the seasonal and interannual variations of biogenic CO2 fluxes in Amazonia. The system assimilated surface measurements of atmospheric CO2 mole fractions made over more than 100 sites over the globe into an atmospheric transport model. This study added four surface stations located in tropical South America, a region poorly covered by CO2 observations. The estimates of net ecosystem exchange (NEE) optimized by the inversion were compared to independent estimates of NEE upscaled from eddy-covariance flux measurements in Amazonia, and against reports on the seasonal and interannual variations of the land sink in South America from the scientific literature. We focused on the impact of the interannual variation of the strong droughts in 2005 and 2010 (due to severe and longer-than-usual dry seasons), and of the extreme rainfall conditions registered in 2009. The spatial variations of the seasonal and interannual variability of optimized NEE were also investigated. While the inversion supported the assumption of strong spatial heterogeneity of these variations, the results revealed critical limitations that prevent global inversion frameworks from capturing the data-driven seasonal patterns of fluxes across Amazonia. In particular, it highlighted issues due to the configuration of the observation network in South America and the lack of continuity of the measurements. However, some robust patterns from the inversion seemed consistent with the abnormal moisture conditions in 2009.

Daily precipitation characteristics of RegCM4 and WRF in China and their interannual variations

2020 ◽  
Vol 82 ◽  
pp. 97-115
Author(s):  
X Kong ◽  
A Wang ◽  
X Bi ◽  
J Wei
Keyword(s):  
Extreme Precipitation ◽  
Climate Models ◽  
Daily Precipitation ◽  
Regional Climate ◽  
Precipitation Amount ◽  
Extreme Rainfall ◽  
Horizontal Resolution ◽  
Interannual Variations ◽  
Precipitation Frequency ◽  
Precipitation Characteristics

To evaluate and clarify the daily precipitation characteristics (i.e. amount, frequency and intensity) of the regional climate models (RCMs) in China, long-term simulations were carried out using RegCM4.5 and Weather Research and Forecasting model (WRF), which were nested within the European Centre for Medium-Range Weather Forecasts (ECMWF)’s 20th century reanalysis (ERA-20C) between 1901 and 2010. The 2 RCMs were initially run at a resolution of 50 km. Analyses mainly compared the model-simulated climatic means and interannual variations of precipitation characteristics with those of dense and high-quality station observations (STN) from 1961-2010. Both models satisfactorily reproduced the seasonal mean precipitation amount, but they overestimated its frequency and underestimated its intensity. Extreme rainfall frequency was also underestimated by both RCMs. In winter (DJF), the interannual variabilities in dry days, light precipitation and moderate precipitation were well represented by both models. However, they poorly reproduced the counterparts of extreme precipitation in winter. In summer (JJA), the 2 RCMs performed well in simulating the interannual variability of extreme precipitation. Comparably, RegCM outperformed WRF in reproducing the spatial patterns of precipitation amount, interannual variations in extreme precipitation and rain events. By contrast, WRF better represented precipitation frequency in different sub-regions overall. Moreover, when the horizontal resolution of RegCM was increased from 50 to 25 km, there was a slight improvement in the representation of precipitation amount and intensity. Our results show that RCMs perform well in reproducing actual climatic means and interannual variations of daily precipitation characteristics in China, and that high-resolution RCM simulations can produce improved results for precipitation amount and intensity.

scholarly journals On the ability of a global atmospheric inversion to constrain variations of CO<sub>2</sub> fluxes over Amazonia

2015 ◽  
Vol 15 (14) ◽  
pp. 8423-8438 ◽  
Author(s):  
L. Molina ◽  
G. Broquet ◽  
P. Imbach ◽  
F. Chevallier ◽  
B. Poulter ◽  
...  
Keyword(s):  
South America ◽  
Amazon Basin ◽  
Transport Model ◽  
Net Ecosystem Exchange ◽  
Extreme Rainfall ◽  
Atmospheric Composition ◽  
Interannual Variations ◽  
The Impact ◽  
Seasonal And Interannual Variations ◽  
Atmospheric Inversion

Abstract. The exchanges of carbon, water and energy between the atmosphere and the Amazon basin have global implications for the current and future climate. Here, the global atmospheric inversion system of the Monitoring of Atmospheric Composition and Climate (MACC) service is used to study the seasonal and interannual variations of biogenic CO2 fluxes in Amazonia during the period 2002–2010. The system assimilated surface measurements of atmospheric CO2 mole fractions made at more than 100 sites over the globe into an atmospheric transport model. The present study adds measurements from four surface stations located in tropical South America, a region poorly covered by CO2 observations. The estimates of net ecosystem exchange (NEE) optimized by the inversion are compared to an independent estimate of NEE upscaled from eddy-covariance flux measurements in Amazonia. They are also qualitatively evaluated against reports on the seasonal and interannual variations of the land sink in South America from the scientific literature. We attempt at assessing the impact on NEE of the strong droughts in 2005 and 2010 (due to severe and longer-than-usual dry seasons) and the extreme rainfall conditions registered in 2009. The spatial variations of the seasonal and interannual variability of optimized NEE are also investigated. While the inversion supports the assumption of strong spatial heterogeneity of these variations, the results reveal critical limitations of the coarse-resolution transport model, the surface observation network in South America during the recent years and the present knowledge of modelling uncertainties in South America that prevent our inversion from capturing the seasonal patterns of fluxes across Amazonia. However, some patterns from the inversion seem consistent with the anomaly of moisture conditions in 2009.

The Influence of Geographical Factors on Extreme Rainfalls in Lampung Province

2019 ◽  
Vol 1 (1) ◽  
pp. 33
Author(s):  
M Welly
Keyword(s):  
Geographical Location ◽  
Daily Rainfall ◽  
Extreme Rainfall ◽  
Design Flood ◽  
Extreme Rainfall Events ◽  
Rainfall Events ◽  
Ungauged Basin ◽  
Flood Discharge ◽  
Design Rainfall ◽  
Geographical Factors

Many people in Indonesia calculate design rainfall before calculating the design flooddischarge. The design rainfall with a certain return period will eventually be convertedinto a design flood discharge by combining it with the characteristics of the watershed.However, the lack of a network of rainfall recording stations makes many areas that arenot hydrologically measured (ungauged basin), so it is quite difficult to know thecharacteristics of rain in the area concerned. This study aims to analyze thecharacteristics of design rainfall in Lampung Province. The focus of the analysis is toinvestigate whether geographical factors influence the design rainfall that occurs in theparticular area. The data used in this study is daily rainfall data from 15 rainfallrecording stations spread in Lampung Province. The method of frequency analysis usedin this study is the Gumbel method. The research shows that the geographical location ofan area does not have significant effect on extreme rainfall events. The effect of risingearth temperatures due to natural exploitation by humans tends to be stronger as a causeof extreme events such as extreme rainfall.Keywords: Influence, geographical, factors, extreme, rainfall.

Trend of Extreme Precipitations Indices in West-central Côte d’Ivoire: Case of the Lobo Watershed

2020 ◽  
Vol 5 (10) ◽  
pp. 1281-1287
Author(s):  
F. B. Allechy ◽  
M. Youan Ta ◽  
V. H. N’Guessan Bi ◽  
F. A. Yapi ◽  
A. B. Koné ◽  
...  
Keyword(s):  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Crop Yields ◽  
Extreme Rainfall ◽  
Cote D’Ivoire ◽  
West Central ◽  
Côte D'ivoire ◽  
Northern Half ◽  
Agricultural Potential ◽  
Annual Total

The Lobo watershed located in the west-central part of Côte d'Ivoire is an area with high agricultural potential, influenced by climate variations and changes that reduce crop yields. The objective of this study is to analyse trends in ETCCDI extreme rainfall indices from rainfall data from 1984 to 2013 using ClimPACT2 software. This study shows that the trend of the indices: number of consecutive wet days (CWD), number of rainy days (R1mm) and the cumulative annual total rainfall (PRCPTOT) is decreasing. On the other hand, the number of consecutive dry days (CDD) is on the rise. In general, the whole basin has experienced a decrease in rainfall as well as wet sequences and an increase in dry sequences. These different trends observed in this study are more pronounced in the northern half of the watershed.

Economic Impact of Sugarcane Variety CO-86032 on Farmers Economy in Maharashtra

2020 ◽  
pp. 354-359
Keyword(s):  
Economic Impact ◽  
Production Technology ◽  
Economic Benefit ◽  
Extreme Rainfall ◽  
Sugar Recovery ◽  
Sugarcane Variety ◽  
Public Research ◽  
Productivity Improvement ◽  
Farming Community ◽  
The Government

The area under sugarcane in Maharashtra state was found to be more stable and consistent rather than production and productivity. It may be due to the F & RP of sugarcane. In the year 1996, MPKV, Rahuri released a promising variety of sugarcane viz., Co-86032 which is very famous in farming community due to its hardiness, sugar recovery (percent) and resistance to the extreme rainfall as well as deficit rainfall. The total economic worthiness of university released sugarcane variety Co-86032(production technology) over other competing varieties of sugarcane in the Maharashtra was `51449.14per ha. The sugarcane growers in Maharashtra state earned net economic benefit of `11059.40 crores from improved sugarcane variety Co-86032. Therefore, it is suggested that the Government should allocate substantial funds to public research in sugarcane for productivity improvement.

Effects of extreme rainfall and drought events on grassland ecosystems

2014 ◽  
Vol 38 (9) ◽  
pp. 1008-1018 ◽  
Author(s):  
ZHANG Bin ◽  
◽  
ZHU Jian-Jun ◽  
LIU Hua-Min ◽  
and PAN Qing-Min
Keyword(s):  
Extreme Rainfall ◽  
Grassland Ecosystems

Soil Moisture Deficits in South-Central Sweden

1989 ◽  
Vol 20 (2) ◽  
pp. 109-122 ◽  
Author(s):  
Lotta Andersson
Keyword(s):  
Soil Moisture ◽  
Field Capacity ◽  
Interannual Variations ◽  
Neutron Probe ◽  
South Central ◽  
Normal Ranges ◽  
Moisture Fluxes ◽  
In The Beginning ◽  
Probe Measurements ◽  
Different Parts

Some commonly used assumptions about climatically induced soil moisture fluxes within years and between different parts of a region were challenged with the help of a conceptual soil moisture model. The model was optimised against neutron probe measurements from forest and grassland sites. Five 10 yrs and one 105 yrs long climatic records, from the province of Östergötland, situated in south-central Sweden, were used as driving variables. It was concluded that some of the tested assumptions should not be taken for granted. Among these were the beliefs that interannual variations of soil moisture contents can be neglected in the beginning of the hydrological year and that soils usually are filled up to field capacity after the autumn recharge. The calculated climatic induced dryness was estimated to be rather insensitive to the choice of climatic stations within the region. Monthly ranges of soil moisture deficits (1883-1987) were shown to be skewed and it is therefore recommended to use medians and standard deviations in statistical analyses of “normal” ranges of soil moisture deficits.

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