Predicting Urban Runoff under Different Surface Conditions in Xi’an, China with DRAINMOD

2012 ◽  
Vol 588-589 ◽  
pp. 2083-2087
Author(s):  
Quan Quan ◽  
Wan Luo ◽  
Bing Shen ◽  
Gao Feng Zhang ◽  
Li Yuan Dong

Increasing impermeable surface area has become a serious burden for drainage of urban stormwater. It is thus important to know how much surface runoff may be generated by storms of varying intensity and duration, especially on a continual daily basis. In this paper, the field hydrology model-DRAINMOD was used to simulate daily surface runoff under different surface condition in Xi’an, China. As a major hydrological components in DRAINMOD, daily evapotranspirations were calculated with the FAO Penman-Monteith method and read into the model. Infiltration parameters were considered as calibration factors in the modeling process. Available data from a local rainfall-runoff experiment were used for model calibration by matching the model predicted surface runoff with the measured values on an event basis. The calibrated model was then used for long term simulations in order to examine the impact of varying climatic conditions and land cover on urban runoff. The modeling results may provide a practical guidance for city storm water management.

2020 ◽  
Vol 24 (5 Part A) ◽  
pp. 2845-2855
Author(s):  
Stanimir Zivanovic ◽  
Ivana Tosic

The Djerdap National Park in Serbia is vulnerable to fires. The variability of a fire in the Djerdap National Park is studied depending on the impact of climatic conditions. The influence was investigated on a yearly, monthly, and daily basis using data recorded at the meteorological station Veliko Gradiste. Data were analyzed for two periods: 1961-1990 and 1991-2017, and for the year of 2011. Special attention is devoted to the conditions for the emergence of the largest forest fire in the Djerdap National Park in September 2011. In this study, the Angstrom index, the Nesterov index, and method of deficit and surplus of precipitation are used to predict the risk of fire. There was an increased danger of fire in the forests in the period of 1991-2017 compared to the period of 1961-1990. Indices showing fire risk are increased for the months of June, July, and August. The September 2011 is characterized by an increase of average monthly air temperature by 3.7?C and a reduction of the total monthly rainfall of 32.3 mm compared to a long-term average value which favorable influenced to the occurrence of large forest fires.


2011 ◽  
Vol 52 (No. 6) ◽  
pp. 239-244 ◽  
Author(s):  
P. Kovář

The paper is focused on the impact of land use changes on water regime. First, an emphasis was given to what extent the main components of the water balance on the experimental catchment Všeminka (region Vsetínské Hills) were influenced. For this reason, the WBCM-5 model was implemented for the period of 10 years in a daily step with a particular reference to simulate the components of direct runoff and of subsurface water recharge. In the selected years of the period 1990–2000, the major changes were made in land use and also the significant fluctuation of rainfall-runoff regimes were observed (e.g. dry year 1992 and flood year 1997). After WBCM-5 parameter calibration it was found that some water balance components can change in relation to substantial land use changes even up to tens of percent in a balance-consideration, i.e. in daily, monthly and yearly or decade values, namely the components of interception and also of direct runoff and of subsurface water recharge. However, a different situation appears when investigating significant short-term rainfall-runoff processes. There were about seven real flood events analysed using the model KINFIL-2 (time step 0.5 hr) during the same period of about 10 years on the same catchment. Furthermore, some land use change positive or negative scenarios were also analysed there. As opposed to long-term water balance analyses, there was never achieved any greater differences in the hydrograph peak or volume than 10%. Summarising, it is always important to distinguish a possible land use change impact in either long-term balance or short-term runoff consideration, otherwise a misunderstanding might be easily made, as can often be found when commenting on the impact on floods in some mass media.


2019 ◽  
Vol 10 (04) ◽  
pp. 1950013
Author(s):  
CRISTINA CATTANEO ◽  
EMANUELE MASSETTI

This paper analyzes whether migration is an adaptation strategy that households employ to cope with climate in Nigeria. We estimate our model using the cross-sectional variation in climate and long-term migration decisions because we are interested in the average response to long-term climatic conditions. For households that operate farms, we find that the relationship between climate and migration is nonlinear. In particular, climates closer to ideal farming conditions are associated with a higher propensity to migrate, whereas in the least favorable climatic conditions, the propensity to migrate declines. The marginal effect of rainfall and temperature changes on migration varies by season. We estimate the impact of climate change on the number of migrant households in 2031–2060 and 2071–2100, ceteris paribus. With current population levels, climate change generates between 3.6 and 6.3 million additional migrants, most of them being internal. However, these estimates are not statistically significant.


Energies ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2745 ◽  
Author(s):  
Fotiou ◽  
Vita ◽  
Capros

The paper presents a newly developed economic-engineering model of the buildings sector and its implementation for all the European Union (EU) Member States (MS), designed to study in detail ambitious energy efficiency strategies and policies, in the context of deep decarbonisation in the long term. The model has been used to support the impact assessment study that accompanied the European Commission’s communication “A Clear Planet for All”, in November 2018. The model covers all EU countries with a fine resolution of building types, and represents agent decision-making in a complex and dynamic economic-engineering mathematical framework. Emphasis is given to behaviours driving the energy renovation of buildings and the ensuing choice of equipment for heating and cooling. The model represents several market and non-market policies that can influence energy decisions in buildings and promote deep energy renovation. Moreover, the paper presents key applications for supporting policies targeting ambitious reduction of energy consumption and carbon emissions in buildings across Europe. The results illustrate that the achievement of ambitious energy-efficiency targets in the long-term heavily depends on pursuing a fast and extensive renovation of existing buildings, at annual rates between 1.21% and 1.77% for the residential sector and between 0.92% to 1.35% for the services sector. In both cases, the renovation rates are far higher past trends. Strong policies aimed at removing non-market barriers are deemed necessary. Electrification constitutes a reasonable choice for deeply renovated buildings and, as a result, almost 50% of households chooses electric heating over gas heating in the long term. However, heat pumps need to exploit further their learning potential to be economical and implementable for the various climatic conditions in Europe. The results also show that the cost impacts are modest even if renovation and decarbonisation in buildings develop ambitiously in the EU. The reduced energy bills due to energy savings can almost offset the increasing capital expenditures. Fundraising difficulties and the cost of capital are, however, of concern.


1992 ◽  
Vol 25 (11) ◽  
pp. 69-76 ◽  
Author(s):  
S. Li ◽  
J. Migita

A mathematical model is developed to predict the runoff of pesticides from paddy field to a river. The model describes the long term runoff as a function of physical-chemical properties of pesticides, cultural practices and climatic conditions. It is assumed that the adsorption and desorption of pesticides between soil and water phases are in equilibrium state, while the degradation in water and soil and the evaporation from water to atmosphere are of first-order reaction. The model is used to examine the relationships between the seasonal amounts of pesticide runoff and their environmental dynamic factors. A four-stage evaluation system is proposed to assess the impact of the runoff on drinking water by taking into account the amount of application, runoff ratio, toxicity and the possibility of being removed from raw water by water purification processes. The model simulates the daily variation of contaminant level in river water, thereby providing a basis for making recommendations for pesticide usage and water management for rice cultivation.


2018 ◽  
Vol 2 ◽  
pp. e25766 ◽  
Author(s):  
Sofie Meeus

Although tropical rainforests play an important role in regulating the world’s climate, they are at the same time particularly vulnerable to changes in the climate. Intense and prolonged droughts, for instance, can lead to biomass loss which will further accelerate these changes. Especially for tree species it becomes problematic, due to their long lifespan, to quickly adapt to or evade unfavorable climatic conditions affecting the composition of the forest community as a whole and consequently the ecosystem services that the rainforests provide. A long-term drying trend currently threatens tropical regions worldwide but is especially strong in the central African rainforest, the second-largest rainforest on Earth. The impact of this decrease in precipitation on the vegetation is, however, still largely unknown due to the limited amount of historical eco-climatological data. Fortunately, these kind of data do exist albeit in a poorly accessible (analog) format in herbarium collections. To investigate if trees show changes in morphology and/or physiology invoked by climatic changes in the last century, the COBECORE team (Congo Basin Eco-Climatological Data Recovery and Valorization”) is exploring the usability of herbaria as potential sources of plant leaf functional trait data using established protocols adjusted to dried leaf material. Photosynthesis as well as gas exchange and transpiration are processes regulated by a plant’s leaves, and depend on the specific leaf area (SLA) and the number and size of the stomata. The less area the latter structures occupy on the leaf the less the plant will suffer from water losses which increases the resistance to drought of plants. We explored the recently digitized African Herbarium of the Botanic Garden Meise which contains over 1.2 million African specimens with a very good coverage of the Congo Basin, dating back to 1880. Currently, we obtained average SLA measurements for 833 herbarium specimens from 59 of the most common tree species of central African rainforests. Pictures for stomata counts and size measurements were taken from over one hundred specimens mainly focused on three Prioria species, giant tree species (up to 60 metres) currently suffering from overexploitation. The data generated in this project will be valuable to understand some lower-level vegetation responses such as plant water use needed to model and predict long-term climate change impacts on vegetation.


2017 ◽  
Vol 49 (1) ◽  
pp. 72-89 ◽  
Author(s):  
Erik MirHadi Madani ◽  
Per Erik Jansson ◽  
Ian Babelon

Abstract To quantify the role of land cover during a period of climate change, the runoff response is studied for Plynlimon in Wales, UK. The main objective was two-fold: (i) to create a protocol for modeling water balance on a daily basis; and (ii) to describe the extent to which the impact of land-use changes can be identified and supported by the long-term monitoring data of runoff from two neighboring watersheds with different land covers. The process-oriented CoupModel platform was used to set up the model with a well-defined uncertainty for selected parameters. The behavioral ensembles were applied to simulated daily discharge data for the period of 1992–2010 using subjective criteria to reduce the prior 35,000 candidates with a random uniform distribution of 40 parameters. The accepted ensemble was reduced to 100 candidates by accepting the best root-mean-square error (RMSE) on the accumulated residuals during the simulation period. Similar good performance for the entire period and both watersheds was obtained. The differences in interception evaporation accounted for the most important differences between forest and grassland. The obtained residual demonstrated that changes in the forest cover had an impact on the water balance during the first part of the simulation period.


Soil Research ◽  
1992 ◽  
Vol 30 (3) ◽  
pp. 297 ◽  
Author(s):  
BD Kay ◽  
AR Dexter

The tensile strength of aggregates is a dynamic property under field conditions and for any given soil reflects the integration of processes leading to a strengthening and weakening of failure zones. The objectives of this study were to determine if variation in the tensile strength of natural aggregates from a red-brown earth could be related to the combined effects of (a) conditions favouring dispersion of clay and a subsequent increase in strength by cementation on drying and (b) wetting/drying cycles which would result in a decrease in strength. Aggregates were collected from the A horizon of different long-term rotations. The seasonal variation in tensile strength was assessed using data collected in 1988 and unpublished data which had been collected annually between 1978 and 1981. Trends in tensile strength over 5 years confirmed the importance of an interaction between climatic conditions which could lead to increased dispersion of clay and wetting/drying cycles. The extent of weakening of failure zones by wetting/drying cycles varied with the rotation. The nature of the impact of cropping history on tensile strength was dependent on antecedent climatic conditions.


Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6921
Author(s):  
Sebastian Pater

A hybrid photovoltaic-thermal collector (PV-T) with the capability to produce thermal energy and electrical energy simultaneously has attracted the attention of researchers, especially in terms of improving PV-T performance. This study analyses the work of four model installations with PV-T and other devices built in the transient systems simulation program. The novelty of this article lies in a long-term approach to the operation of PV-T panels under selected climatic conditions. Influence of the installation’s configuration on the obtained temperatures of solar cells, and, in consequence, on electric power generated by PV-T and the amount of heat produced during one year in a selected location is presented. Among others, the impact of the temperature coefficient of photovoltaic cells for long-term PV-T operation was analyzed in the paper. The results showed that the type of cell used may decrease the yearly electric energy production from PV-T even by 7%. On the other hand, intensification of the process of heat reception from PV-T using a heat pump increased this production by 6% in relation to the base model. The obtained research results indicate possible methods for improving the effectiveness of PV-T operation in a long-term aspect.


Author(s):  
Adrienn Széles, Éva Horváth, Attila Vad, Endre Harsányi

Climate change poses a new challenge for maize producers which calls for the re-thinking of each production technological element. Professional nutrient replenishment may represent an alternative for the mitigation of yield decrease caused by climate change by means of improving yield stability from the aspect of global food safety, as well as increasing yield and improving yield quality. In the course of a  six-year (2011-2016) research, under changing climatic conditions we studied how different fertilization methods - 11 different N doses (0-300 kg ha-1) - affect the productivity of maize and protein content of grains.The experiment was carried out in Hungary (47o 33’ N, 21o 26’ E, asl: 111 m) in the long-term experiment of the University of Debrecen.


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