Observed and Predicted Precipitation Changes in Pakistan Using Ground Observations, Satellite Data and Model Projections with Special Focus on Winter and Pre-Monsoon Precipitation

2021 ◽  
Author(s):  
Fasiha Safdar ◽  
Muhammad Fahim Khokhar ◽  
Fatimah Mahmood ◽  
Muhammad Zeeshan ◽  
Muhammad Arshad
Keyword(s):  
Winter Precipitation ◽  
Mean Bias Error ◽  
Special Focus ◽  
Monthly Precipitation ◽  
Negative Consequences ◽  
Monsoon Precipitation ◽  
Data Set ◽  
Climatic Zones ◽  
Climate System Model ◽  
Precipitation Changes

Abstract This study utilizes ground, satellite and model data to investigate the observed and future precipitation changes in Pakistan. Pakistan Meteorological Department’s (PMD) monthly precipitation data set along with Tropical Rainfall Measuring Mission (TRMM) monthly dataset TRMM_3B43 (0.25˚x0.25˚ resolution) have been used to evaluate rainfall trends over the climatic zones of Pakistan through Man-Kendall test and Sen’s slope estimator for the time period 1978-2018. Community Climate System Model (CCSM4) projections have been employed to explore the projected changes in precipitation till 2099. Furthermore, TRMM and CCSM4 projections have been correlated and validated using Root Mean Square Error (RMSE) and Mean Bias Error (MBE). There is a good correlation between TRMM and PMD ground observation at all stations of the country for all seasons, with correlation coefficient values ranging from 0.89 (November) to 0.97 (July and August). The study shows a decreasing trend in winter precipitation in all zones of the country with a significant decrease over western mountains i.e. zone C of the country. During 2008-2018, a sharp decrease in winter precipitation is observed as compared to the baseline value of 1978-2007 in all climatic zones. There seems to be a shift in precipitation from winter towards pre-monsoon season as pre-monsoon precipitation in last 11 years increased in all zones except Zone C. Coherently, there is a decrease in area affected by winter precipitation and an increase in area for pre-monsoon precipitation. Future precipitation estimates from CCSM4 model for RCP 4.5 and RCP 8.5 over-estimate precipitation in most parts of the country for the first 9 observed years (2010-2018) and predict a rise in precipitation by 2099 which is more pronounced in the northern and western Pakistan while a decrease is predicted for the plains of the country, which might have negative consequences for agriculture.

scholarly journals Long term Temperature and Precipitation Trends Assessment in the state of Qatar and its Implication to Energy Water and Food Nexus

2021 ◽  
Author(s):  
Al-Ansari Tareq ◽  
Govindan Rajesh ◽  
Hazrat Bilal
Keyword(s):  
Decision Making ◽  
Winter Precipitation ◽  
Decision Making Process ◽  
Monthly Precipitation ◽  
Seasonal Temperature ◽  
Security Assessment ◽  
Negative Consequences ◽  
Temperature And Precipitation ◽  
Trade Offs

Abstract Climate change is one of the most severe global challenges of the present generation. Variations in temperature and precipitation can seriously affect water energy, water and food (EWF) security. Assessment of the ground-based observation of the climatic parameters such as temperature and precipitation are vital for the overall decision-making process concerning energy, water and food security. In this study, temperature and precipitation data is investigated using the Mann Kendall, Pettitt and Watson tests and inter-annual variability assessment. Long-term temperature data indicates that the annual and seasonal temperature has increased significantly between 1987 and 2016. The mean temperature has increased by 1.02 ℃ over the period of observation. In contrast, the study determines that precipitation during the period of observation decreased by -12.6 mm. However, this decreasing trend is not statistically significant (p < 0.05). Furthermore, total monthly precipitation is observed to be decreasing during the winter (December-January-February-DJF) while increasing in spring (March-April-May-MAM), summer (June-July-August-JJA) and autumn (September-October-November-SON). Despite the observed increases in the seasonal temperature during JJA, MAM and SON, the decreasing trend in winter precipitation is of more concern as most of the rainfall is received during DJF. These results have serious implications for EWF resources and the ‘nexus’ between them. Such integrated resource management approaches not only lower the risks of a one-dimensional decision-making process, it can also identify interdependencies, synergies, and trade-offs amongst the EWF sectors. As an outcome of the calculated trends, this study recommends measures to improve the overall resilience of EWF sectors and to adapt and mitigate the negative consequences of the changing climate faced by these sectors.

scholarly journals Validation of CHIRPS Precipitation Estimates over Taiwan at Multiple Timescales

2021 ◽  
Vol 13 (2) ◽  
pp. 254 ◽  
Author(s):  
Jie Hsu ◽  
Wan-Ru Huang ◽  
Pin-Yi Liu ◽  
Xiuzhen Li
Keyword(s):  
Annual Cycle ◽  
Interannual Variation ◽  
Winter Precipitation ◽  
Monthly Precipitation ◽  
Precipitation Estimation ◽  
Precipitation Estimates ◽  
Precipitation Variation ◽  
Global Precipitation ◽  
Multiple Timescale ◽  
Better Than

The Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS), which incorporates satellite imagery and in situ station information, is a new high-resolution long-term precipitation dataset available since 1981. This study aims to understand the performance of the latest version of CHIRPS in depicting the multiple timescale precipitation variation over Taiwan. The analysis is focused on examining whether CHIRPS is better than another satellite precipitation product—the Integrated Multi-satellitE Retrievals for Global Precipitation Mission (GPM) final run (hereafter IMERG)—which is known to effectively capture the precipitation variation over Taiwan. We carried out the evaluations made for annual cycle, seasonal cycle, interannual variation, and daily variation during 2001–2019. Our results show that IMERG is slightly better than CHIRPS considering most of the features examined; however, CHIRPS performs better than that of IMERG in representing the (1) magnitude of the annual cycle of monthly precipitation climatology, (2) spatial distribution of the seasonal mean precipitation for all four seasons, (3) quantitative precipitation estimation of the interannual variation of area-averaged winter precipitation in Taiwan, and (4) occurrence frequency of the non-rainy grids in winter. Notably, despite the fact that CHIRPS is not better than IMERG for many examined features, CHIRPS can depict the temporal variation in precipitation over Taiwan on annual, seasonal, and interannual timescales with 95% significance. This highlights the potential use of CHIRPS in studying the multiple timescale variation in precipitation over Taiwan during the years 1981–2000, for which there are no data available in the IMERG database.

scholarly journals A Spatial and Temporal Assessment of Vegetation Greening and Precipitation Changes for Monitoring Vegetation Dynamics in Climate Zones over Africa

2021 ◽  
Vol 10 (3) ◽  
pp. 129
Author(s):  
Vincent Nzabarinda ◽  
Anming Bao ◽  
Wenqiang Xu ◽  
Solange Uwamahoro ◽  
Madeleine Udahogora ◽  
...  
Keyword(s):  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Forest Type ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Plant Health ◽  
Tree Cover ◽  
Climatic Zones ◽  
Dramatic Decline ◽  
Precipitation Changes

Vegetation is vital, and its greening depends on access to water. Thus, precipitation has a considerable influence on the health and condition of vegetation and its amount and timing depend on the climatic zone. Therefore, it is extremely important to monitor the state of vegetation according to the movements of precipitation in climatic zones. Although a lot of research has been conducted, most of it has not paid much attention to climatic zones in the study of plant health and precipitation. Thus, this paper aims to study the plant health in five African climatic zones. The linear regression model, the persistence index (PI), and the Pearson correlation coefficients were applied for the third generation Normalized Difference Vegetation Index (NDVI3g), with Climate Hazard Group infrared precipitation and Climate Change Initiative Land Cover for 34 years (1982 to 2015). This involves identifying plants in danger of extinction or in dramatic decline and the relationship between vegetation and rainfall by climate zone. The forest type classified as tree cover, broadleaved, deciduous, closed to open (>15%) has been degraded to 74% of its initial total area. The results also revealed that, during the study period, the vegetation of the tropical, polar, and warm temperate zones showed a higher rate of strong improvement. Although arid and boreal zones show a low rate of strong improvement, they are those that experience a low percentage of strong degradation. The continental vegetation is drastically decreasing, especially forests, and in areas with low vegetation, compared to more vegetated areas, there is more emphasis on the conservation of existing plants. The variability in precipitation is excessively hard to tolerate for more types of vegetation.

scholarly journals Numerical simulations of spreading of the Persian Gulf outflow into the Oman Sea

Ocean Science ◽  
2010 ◽  
Vol 6 (4) ◽  
pp. 887-900 ◽  
Author(s):  
M. Ezam ◽  
A. A. Bidokhti ◽  
A. H. Javid
Keyword(s):  
Persian Gulf ◽  
Bottom Topography ◽  
World Ocean ◽  
Monthly Precipitation ◽  
Boundary Current ◽  
Surface Salinity ◽  
Data Set ◽  
Open Boundaries ◽  
The Mean ◽  
The Persian Gulf

Abstract. A three dimensional numerical model namely POM (Princeton Ocean Model) and observational data are used to study the Persian Gulf outflow structure and its spreading pathways during 1992. In the model, the monthly wind speed data were taken from ICOADS (International Comprehensive Ocean-Atmosphere Data Set) and the monthly SST (sea surface temperatures) were taken from AVHRR (Advanced Very High Resolution Radiometer) with the addition of monthly net shortwave radiations from NCEP (National Center for Environmental Prediction). The mean monthly precipitation rates from NCEP data and the calculated evaporation rates are used to impose the surface salinity fluxes. At the open boundaries the temperature and salinity were prescribed from the mean monthly climatological values from WOA05 (World Ocean Atlas 2005). Also the four major components of the tide were prescribed at the open boundaries. The results show that the outflow mainly originates from two branches at different depths in the Persian Gulf. The permanent branch exists during the whole year deeper than 40 m along the Gulf axis and originates from the inner parts of the Persian Gulf. The other seasonal branch forms in the vicinity of the shallow southern coasts due to high evaporation rates during winter. Near the Strait of Hormuz the two branches join and form the main outflow source water. The results of simulations reveal that during the winter the outflow boundary current mainly detaches from the coast well before Ras Al Hamra Cape, however during summer the outflow seems to follow the coast even after this Cape. This is due to a higher density of the colder outflow that leads to more sinking near the coast in winter. Thus, the outflow moves to a deeper depth of about 500 m (for which some explanations are given) while the main part detaches and spreads at a depth of about 300 m. However in summer it all moves at a depth of about 200–250 m. During winter, the deeper, stronger and wider outflow is more affected by the steep topography, leading to separation from the coast. While during summer, the weaker and shallower outflow is less influenced by bottom topography and so continues along the boundary.

scholarly journals Measuring ice- and liquid-water properties in mixed-phase cloud layers at the Leipzig Cloudnet station

2016 ◽  
Vol 16 (16) ◽  
pp. 10609-10620 ◽  
Author(s):  
Johannes Bühl ◽  
Patric Seifert ◽  
Alexander Myagkov ◽  
Albert Ansmann
Keyword(s):  
Water Content ◽  
Liquid Water ◽  
Mass Flux ◽  
Mixed Phase ◽  
Cloud Base ◽  
Doppler Velocity ◽  
Special Focus ◽  
Data Set ◽  
Ice Water Content ◽  
Ice Water

Abstract. An analysis of the Cloudnet data set collected at Leipzig, Germany, with special focus on mixed-phase layered clouds is presented. We derive liquid- and ice-water content together with vertical motions of ice particles falling through cloud base. The ice mass flux is calculated by combining measurements of ice-water content and particle Doppler velocity. The efficiency of heterogeneous ice formation and its impact on cloud lifetime is estimated for different cloud-top temperatures by relating the ice mass flux and the liquid-water content at cloud top. Cloud radar measurements of polarization and Doppler velocity indicate that ice crystals formed in mixed-phase cloud layers with a geometrical thickness of less than 350 m are mostly pristine when they fall out of the cloud.

scholarly journals Supplemental Material: Monthly insolation linked to the time-transgressive nature of the Holocene East Asian monsoon precipitation maximum

2021 ◽  
Author(s):  
Xin Zhou ◽  
et al.
Keyword(s):  
Asian Monsoon ◽  
East Asian Monsoon ◽  
East Asian ◽  
Monsoon Precipitation ◽  
The Holocene ◽  
Precipitation Changes

Supplemental information on the records used, the chronological framework of different sites, reconstructions of precipitation changes, and the defined time of the Holocene monsoon precipitation maximum.<br>

scholarly journals Development of a daily gridded precipitation data set for the Middle East

2008 ◽  
Vol 12 ◽  
pp. 165-170 ◽  
Author(s):  
A. Yatagai ◽  
P. Xie ◽  
P. Alpert
Keyword(s):  
Middle East ◽  
Climate Models ◽  
Daily Precipitation ◽  
Rain Gauge ◽  
Monthly Precipitation ◽  
Data Set ◽  
Key Points ◽  
Fertile Crescent ◽  
Precipitation Analysis ◽  
The Impact

Abstract. We show an algorithm to construct a rain-gauge-based analysis of daily precipitation for the Middle East. One of the key points of our algorithm is to construct an accurate distribution of climatology. One possible advantage of this product is to validate high-resolution climate models and/or to diagnose the impact of climate changes on local hydrological resources. Many users are familiar with a monthly precipitation dataset (New et al., 1999) and a satellite-based daily precipitation dataset (Huffman et al., 2001), yet our data set, unlike theirs, clearly shows the effect of orography on daily precipitation and other extreme events, especially over the Fertile Crescent region. Currently the Middle-East precipitation analysis product is consisting of a 25-year data set for 1979–2003 based on more than 1300 stations.

scholarly journals ANALYSING FACTORS FOR COMMUNITY PARTICIPATION IN TOURISM DEVELOPMENT

2019 ◽  
Vol 9 (1) ◽  
pp. 39
Author(s):  
Heri Puspito Diyah Setiyorini ◽  
Rini Andari ◽  
Juju Masunah
Keyword(s):  
Community Participation ◽  
Public Awareness ◽  
Tourism Development ◽  
Local Communities ◽  
Government Support ◽  
Community Collaboration ◽  
Infrastructure Development ◽  
Negative Consequences ◽  
Data Set ◽  
Place Satisfaction

This study aims to understand the perceptions of local communities to participate in tourism development. The method used in the research is a quantitative approach. Questionnaires were distributed to local communities in major destinations in Bandung, West Java, Indonesia. There were 200 data set analyzed by factor analysis. The result showed that from 28 indicators of community participation, eight groups of factors formed. The groups are 1) place attachments; 2) perception of negative consequences; 3) Community Involvement; 4) Infrastructure Development; 5) Place Satisfaction; 6) Economic Benefit; 7) Government Support; 8) Community Collaboration. This result also shows that place attachment, perception of negative consequences, place satisfaction, and community collaboration have higher factor loading compares to other groups. The finding implies that in gaining community participation, these factors could be considered as the essence of communication message in raising public awareness and participation for tourism development.

scholarly journals SOLIDARITY CHECK IN TIMES OF COVID-19. ANALYSIS OF THE EU APPROACH TOWARDS ITS CLOSEST NEIGHBOURS WITH A SPECIAL FOCUS ON MONTENEGRO

2021 ◽  
Author(s):  
Stefan Đurić ◽  
Bojana Lalatović
Keyword(s):  
European Union ◽  
Complex Structure ◽  
Special Focus ◽  
The European Union ◽  
Negative Consequences ◽  
Western Balkans ◽  
Governance System ◽  
Member States ◽  
Balkan Countries ◽  
The Eu

Solidarity as one of the cornerstone values of the European Union has been once again seated on the red chair and intensively discussed within the European Union and broader. After the economic recession and migrant crisis that marked the last two decades, the outbreak of the COVID-19 pandemic has once again harshly tested the fundamental objectives and values of the European Union and the responsiveness and effectiveness of its governance system on many fronts. In April, 2020 several EU Member States were among the worst affected countries worldwide and this situation soon became similar in their closest neighbourhood. It put a huge pressure on the EU to act faster, while at the same time placing this sui generis community to the test that led to revealing its strengths and weaknesses. As it happened in the previous crises, the Union launched policies and various programmes that were meant to lessen the burden of the Member States and aspiring countries caused by the crises. The objectives of the mentioned soft law instruments that the EU adopted during the COVID-19 crisis has been not only to show that EU law is equipped to react to health and economic crises rapidly but to deliver its support in terms of solidarity to its Member States and its closest neighbours facing the unprecedented health and economic crisis. This article will explore the value and implication of the solidarity principle in times of Covid-19 in its various manifestations. A special focus will be on the financial and material aspects of the EU instruments created to combat the negative consequences of the pandemic and their further impact on shaping the solidarity principle within the EU system. While examining the character and types of these mechanisms a special focus will be placed on those available to Western Balkan countries, whereas Montenegro as the “fast runner” in the EU integration process will be taken as a case study for the purpose of more detailed analyses. One of the major conclusions of the paper will be that although the speed of the EU reactions due to highly complex structure of decision making was not always satisfying for all the actors concerned, the EU once again has shown that it is reliable and that it treats the Western Balkan countries as privileged partners all for the sake of ending pandemic and launching the socio-economic recovery of the Western Balkans. Analytical and comparative methods will be dominantly relied upon throughout the paper. This will allow the authors to draw the main conclusions of the paper and assess the degree of solidarity as well as the effectiveness of the existing EU instruments that are available to Montenegro and aimed at diminishing negative consequences of the crisis.

Estimating Lost Sales for Substitutable Products with Uncertain On-Shelf Availability

2021 ◽  
Author(s):  
Daniel Steeneck ◽  
Fredrik Eng-Larsson ◽  
Francisco Jauffred
Keyword(s):  
Inventory Management ◽  
Product Category ◽  
Problem Definition ◽  
Lost Sales ◽  
Negative Consequences ◽  
Demand Model ◽  
Data Set ◽  
Probabilistic Choice ◽  
Substitutable Products ◽  
Choice Sets

Problem definition: We address the problem of how to estimate lost sales for substitutable products when there is no reliable on-shelf availability (OSA) information. Academic/practical relevance: We develop a novel approach to estimating lost sales using only sales data, a market share estimate, and an estimate of overall availability. We use the method to illustrate the negative consequences of using potentially inaccurate inventory records as indicators of availability. Methodology: We suggest a partially hidden Markov model of OSA to generate probabilistic choice sets and incorporate these probabilistic choice sets into the estimation of a multinomial logit demand model using a nested expectation-maximization algorithm. We highlight the importance of considering inventory reliability problems first through simulation and then by applying the procedure to a data set from a major U.S. retailer. Results: The simulations show that the method converges in seconds and produces estimates with similar or lower bias than state-of-the-art benchmarks. For the product category under consideration at the retailer, our procedure finds lost sales of around 3.0% compared with 0.2% when relying on the inventory record as an indicator of availability. Managerial implications: The method efficiently computes estimates that can be used to improve inventory management and guide managers on how to use their scarce resources to improve stocking execution. The research also shows that ignoring inventory record inaccuracies when estimating lost sales can produce substantially inaccurate estimates, which leads to incorrect parameters in supply chain planning.

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