scholarly journals Aerosol direct radiative effects over Kanpur in the Indo-Gangetic basin, northern India: Long-term (2001–2005) observations and implications to regional climate

2008 ◽  
Vol 113 (D4) ◽  
Author(s):  
Sagnik Dey ◽  
S. N. Tripathi
Keyword(s):  
Regional Climate ◽  
Radiative Effects ◽  
Northern India

scholarly journals Extreme smog challenge of India intensified by increasing lower tropospheric stability

2021 ◽  
Author(s):  
Ritesh Gautam ◽  
Piyushkumar Patel ◽  
Manoj Singh ◽  
Tianjia Liu ◽  
Loretta Mickley ◽  
...  
Keyword(s):  
Air Quality ◽  
Lower Troposphere ◽  
Mitigation Strategies ◽  
Radiative Effects ◽  
Surface Cooling ◽  
Northern India ◽  
Lower Tropospheric Stability ◽  
Autumn And Winter ◽  
Aerosol Radiative Effects

Extreme smog in India widely impacts air quality in late autumn and winter months. While the links between emissions and air quality are well-recognized, the association of smog and its intensification with climatic trends in the lower troposphere, where aerosol pollution and its radiative effects manifest, are not understood well. Here we use long-term satellite data to show a significant increase in aerosol exceedances over northern India, resulting in sustained atmospheric warming and surface cooling over the last two decades. We find several lines of evidence suggesting these aerosol radiative effects have induced a multidecadal (1980-2019) strengthening of lower tropospheric stability and an increase in relative humidity, leading to over fivefold increase in poor visibility days. Given this crucial aerosol-radiation-meteorological feedback driving the smog intensification, we anticipate results from this study will help inform mitigation strategies supporting stronger region-wide measures, which are critical for solving the smog challenge in India.

scholarly journals Future Changes in Wave Conditions at the German Baltic Sea Coast Based on a Hybrid Approach Using an Ensemble of Regional Climate Change Projections

Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 167
Author(s):  
Norman Dreier ◽  
Edgar Nehlsen ◽  
Peter Fröhle ◽  
Diana Rechid ◽  
Laurens M. Bouwer ◽  
...  
Keyword(s):  
21St Century ◽  
Wind Wave ◽  
Regional Climate ◽  
Hybrid Approach ◽  
Wave Modelling ◽  
Long Term Changes ◽  
Mean Wave Period ◽  
Wave Conditions ◽  
Sea Coast

In this study, the projected future long-term changes of the local wave conditions at the German Baltic Sea coast over the course of the 21st century are analyzed and assessed with special focus on model agreement, statistical significance and ranges/spread of the results. An ensemble of new regional climate model (RCM) simulations with the RCM REMO for three RCP forcing scenarios was used as input data. The outstanding feature of the simulations is that the data are available with a high horizontal resolution and at hourly timesteps which is a high temporal resolution and beneficial for the wind–wave modelling. A new data interface between RCM output data and wind–wave modelling has been developed. Suitable spatial aggregation methods of the RCM wind data have been tested and used to generate input for the calculation of waves at quasi deep-water conditions and at a mean water level with a hybrid approach that enables the fast compilation of future long-term time series of significant wave height, mean wave period and direction for an ensemble of RCM data. Changes of the average wind and wave conditions have been found, with a majority of the changes occurring for the RCP8.5 forcing scenario and at the end of the 21st century. At westerly wind-exposed locations mainly increasing values of the wind speed, significant wave height and mean wave period have been noted. In contrast, at easterly wind-exposed locations, decreasing values are predominant. Regarding the changes of the mean wind and wave directions, westerly directions becoming more frequent. Additional research is needed regarding the long-term changes of extreme wave events, e.g., the choice of a best-fit extreme value distribution function and the spatial aggregation method of the wind data.

Media against communication: media/violence and conditionalities of Muslim silencing in Northern India

2021 ◽  
pp. 016344372199453
Author(s):  
Britta Ohm
Keyword(s):  
Political Communication ◽  
Physical Violence ◽  
Media Violence ◽  
New Delhi ◽  
Northern India ◽  
Media And Communication ◽  
The Relationship ◽  
Indian Cities

Understanding the relationship between media and communication as increasingly conflictive under conditions of de-democratization in India, this essay proposes a focus on violence-induced conditionalities of political communication among the affected. I introduce the term ‘media/violence’ as I look at two spaces in North Indian cities that have been turned into ‘Muslim ghettos’ over the past two decades: Jamia Nagar in New Delhi and Juhapura in Ahmedabad (Gujarat). Based on intermittent fieldwork between 2015 and 2020 (partly online), I argue that differences both in the quality of the violence as well as in the interaction between mediated and physical violence executed on the two spaces conditioned long-term options of collective communication (and their absence). The analysis helps us understand how massive political and legal protests could eventually erupt in Jamia Nagar (Shaheen Bagh) in late 2019, while the very reason for protest appears to have eluded residents of Juhapura.

scholarly journals Long-term changes of river discharge regime in Latvia

2008 ◽  
Vol 39 (2) ◽  
pp. 133-141 ◽  
Author(s):  
Maris Klavins ◽  
Valery Rodinov
Keyword(s):  
Climate Variability ◽  
River Discharge ◽  
Water Resource Management ◽  
Regional Climate ◽  
Hydrological Regime ◽  
High Water ◽  
Regime Changes ◽  
Long Term Changes ◽  
Discharge Regime

The study of changes in river discharge is important for regional climate variability characterization and for development of an efficient water resource management system. The hydrological regime of rivers and their long-term changes in Latvia were investigated. Four major types of river hydrological regimes, which depend on climatic and physicogeographic factors, were characterized. These factors are linked to the changes observed in river discharge. Periodic oscillations of discharge, and low- and high-water flow years are common for the major rivers in Latvia. A main frequency of river discharge regime changes of about 20 and 13 years was estimated for the studied rivers. A significant impact of climate variability on the river discharge regime has been found.

scholarly journals Techniques for analyses of trends in GRUAN data

2015 ◽  
Vol 8 (4) ◽  
pp. 1673-1684 ◽  
Author(s):  
G. E. Bodeker ◽  
S. Kremser
Keyword(s):  
Measurement Uncertainty ◽  
Trend Analysis ◽  
Global Climate ◽  
Regional Climate ◽  
Added Value ◽  
Least Squares Regression ◽  
Target Uncertainty ◽  
Reference Quality ◽  
Measurement Uncertainties

Abstract. The Global Climate Observing System (GCOS) Reference Upper Air Network (GRUAN) provides reference quality RS92 radiosonde measurements of temperature, pressure and humidity. A key attribute of reference quality measurements, and hence GRUAN data, is that each datum has a well characterized and traceable estimate of the measurement uncertainty. The long-term homogeneity of the measurement records, and their well characterized uncertainties, make these data suitable for reliably detecting changes in global and regional climate on decadal time scales. Considerable effort is invested in GRUAN operations to (i) describe and analyse all sources of measurement uncertainty to the extent possible, (ii) quantify and synthesize the contribution of each source of uncertainty to the total measurement uncertainty, and (iii) verify that the evaluated net uncertainty is within the required target uncertainty. However, if the climate science community is not sufficiently well informed on how to capitalize on this added value, the significant investment in estimating meaningful measurement uncertainties is largely wasted. This paper presents and discusses the techniques that will need to be employed to reliably quantify long-term trends in GRUAN data records. A pedagogical approach is taken whereby numerical recipes for key parts of the trend analysis process are explored. The paper discusses the construction of linear least squares regression models for trend analysis, boot-strapping approaches to determine uncertainties in trends, dealing with the combined effects of autocorrelation in the data and measurement uncertainties in calculating the uncertainty on trends, best practice for determining seasonality in trends, how to deal with co-linear basis functions, and interpreting derived trends. Synthetic data sets are used to demonstrate these concepts which are then applied to a first analysis of temperature trends in RS92 radiosonde upper air soundings at the GRUAN site at Lindenberg, Germany (52.21° N, 14.12° E).

scholarly journals Modeling the radiative effects of desert dust on weather and regional climate

2013 ◽  
Vol 13 (11) ◽  
pp. 5489-5504 ◽  
Author(s):  
C. Spyrou ◽  
G. Kallos ◽  
C. Mitsakou ◽  
P. Athanasiadis ◽  
C. Kalogeri ◽  
...  
Keyword(s):  
Radiative Transfer ◽  
Regional Climate ◽  
Lower Troposphere ◽  
Integrated Approach ◽  
Dust Particles ◽  
Radiative Transfer Model ◽  
Limited Area ◽  
Transfer Model ◽  
Radiative Effects ◽  
Desert Dust

Abstract. Mineral dust aerosols exert a significant effect on both solar and terrestrial radiation. By absorbing and scattering, the solar radiation aerosols reduce the amount of energy reaching the surface. In addition, aerosols enhance the greenhouse effect by absorbing and emitting outgoing longwave radiation. Desert dust forcing exhibits large regional and temporal variability due to its short lifetime and diverse optical properties, further complicating the quantification of the direct radiative effect (DRE). The complexity of the links and feedbacks of dust on radiative transfer indicate the need for an integrated approach in order to examine these impacts. In order to examine these feedbacks, the SKIRON limited area model has been upgraded to include the RRTMG (Rapid Radiative Transfer Model – GCM) radiative transfer model that takes into consideration the aerosol radiative effects. It was run for a 6 year period. Two sets of simulations were performed, one without the effects of dust and the other including the radiative feedback. The results were first evaluated using aerosol optical depth data to examine the capabilities of the system in describing the desert dust cycle. Then the aerosol feedback on radiative transfer was quantified and the links between dust and radiation were studied. The study has revealed a strong interaction between dust particles and solar and terrestrial radiation, with several implications on the energy budget of the atmosphere. A profound effect is the increased absorption (in the shortwave and longwave) in the lower troposphere and the induced modification of the atmospheric temperature profile. These feedbacks depend strongly on the spatial distribution of dust and have more profound effects where the number of particles is greater, such as near their source.

scholarly journals Climate Change Controls Phosphorus Transport from the Watershed into Lake Kinneret (Israel)

2021 ◽  
Author(s):  
Moshe Gophen
Keyword(s):  
Climate Change ◽  
Regional Climate ◽  
Regional Climate Change ◽  
Lake Kinneret ◽  
Phosphorus Transport ◽  
Efficient Management ◽  
Hula Valley ◽  
Reclamation Project ◽  
The Impact

AbstractPart of the Kinneret watershed, the Hula Valley, was modified from wetlands – shallow lake for agricultural cultivation. Enhancement of nutrient fluxes into Lake Kinneret was predicted. Therefore, a reclamation project was implemented and eco-tourism partly replaced agriculture. Since the mid-1980s, regional climate change has been documented. Statistical evaluation of long-term records of TP (Total Phosphorus) concentrations in headwaters and potential resources in the Hula Valley was carried out to identify efficient management design targets. Significant correlation between major headwater river discharge and TP concentration was indicated, whilst the impact of external fertilizer loads and 50,000 winter migratory cranes was probably negligible. Nevertheless, confirmed severe bdamage to agricultural crops carried out by cranes led to their maximal deportation and optimization of their feeding policy. Consequently, the continuation of the present management is recommended.

scholarly journals Endoscopic Drainage of Pancreatic Pseudocysts: An Experience with 77 Patients

2017 ◽  
Vol 08 (02) ◽  
pp. 061-067
Author(s):  
Hemanta K. Nayak ◽  
Sandeep Kumar ◽  
Uday C. Ghoshal ◽  
Samir Mohindra ◽  
Namita Mohindra ◽  
...  
Keyword(s):  
Long Term Results ◽  
Pancreatic Pseudocysts ◽  
Endoscopic Drainage ◽  
Stent Occlusion ◽  
Northern India ◽  
Short And Long Term ◽  
Transpapillary Drainage ◽  
And Migration ◽  
Lost To Follow Up

ABSTRACT Background: We evaluated short‑ and long‑term results of endoscopic drainage (a minimally invasive nonsurgical treatment) of pancreatic pseudocysts (PPCs) and factors associated with its success at a multilevel teaching hospital in Northern India, as such data are scanty from India. Patients and Methods: Retrospective review of records of consecutive patients undergoing endoscopic drainage of PPC from January 2002 to June 2013 was undertaken. Results: Seventy‑seven patients (56 males), median age 36 years (range, 15–73), underwent endoscopic drainage of PPC with 98% technical success. Pseudocysts drained were symptomatic (duration 11 weeks, range, 8–68), large (volume 582 mL [range, 80–2706]), located in head (n = 32, 46%), body and tail (n = 37, 54%), and infected (n = 39, 49%). Drainage procedures included cystogastrostomy (n = 54, 78%), cystoduodenostomy (n = 9, 13%), transpapillary drainage (n = 2, 3%), and multiple route (n = 4, 6%), with additional endoscopic nasocystic drainage (ENCD) in 41 (59%). Sixty‑nine patients were followed up (median 28 months, range 2–156; other eight lost to follow‑up). Complications (n = 21, 30%) included stent occlusion and migration (13), bleeding (5), perforation (2), and death (1). Endoscopic procedure had to be repeated in 19 patients (28%; 16 for sepsis, 3 for recurrence). The reasons for additional nonendoscopic treatment (n = 8, 12%) included incomplete cyst resolution (3), recurrence (2), bleeding (1), and perforation (2). Overall success rate of endoscopic drainage was 88%. Whereas infected pseudocysts were associated with poorer outcome (odds ratio [OR] 0.016; 95% confidence interval [CI] 0.001–0.037), placement of ENCD led to better results (OR 11.85; 95% CI 1.03–135.95). Conclusion: Endoscopic drainage is safe and effective for PPC.

scholarly journals How Does the Tibetan Plateau Affect the Transition of Indian Monsoon Rainfall?

2007 ◽  
Vol 135 (5) ◽  
pp. 2006-2015 ◽  
Author(s):  
Tomonori Sato ◽  
Fujio Kimura
Keyword(s):  
South Asian ◽  
Summer Monsoon ◽  
Climate Model ◽  
Monsoon Rainfall ◽  
Regional Climate ◽  
Reanalysis Data ◽  
North India ◽  
The Tibetan Plateau ◽  
The South ◽  
Northern India

Abstract The roles of the Tibetan Plateau (TP) upon the transition of precipitation in the south Asian summer monsoon are investigated using a simplified regional climate model. Before the onset of the south Asian monsoon, descending flow in the midtroposphere, which can be considered as a suppressor against precipitation, prevails over northern India as revealed by the NCEP–NCAR reanalysis data. The descending motion gradually weakens and retreats from this region before July, consistent with the northwestward migration of the monsoon rainfall. To examine a hypothesis that the dynamical and thermal effects of TP cause the midtropospheric subsidence and its seasonal variation, a series of numerical experiments are conducted using a simplified regional climate model. The mechanical effect of the TP generates robust descending flow over northern India during winter and spring when the zonal westerly flow is relatively strong, but the effect becomes weaker after April as the westerly flow tends to be weaker. The thermal effect of the TP, contrastingly, enhances the descending flow over north India in the premonsoonal season. The descending flow enhanced by the thermal effect of the TP has a seasonal cycle because the global-scale upper-level westerly changes the energy propagation of the thermal forcing response. The subsidence formed by the mechanical and thermal effects of the TP disappears over northern India after the subtropical westerly shifts north of the plateau, the seasonal change of which is in good agreement with that in the reanalysis data. The retreat of the descending flow can be regarded as the withdrawal of the premonsoon season and the commencement of the south Asian monsoon. After that, the deep convection, indicating the onset of the Indian summer monsoon, is able to develop over north India in relation to the ocean–atmosphere and land–atmosphere interaction processes. Northwest India is known to be the latest region of summer monsoon onset in south Asia. Thus, the thermal and mechanical forcing of the TP has great impact on the transition of the Indian monsoon rainfall by changing the midtropospheric circulation.

Generating long-term high-resolution land-use change datasets for regional climate modeling in CORDEX domains

2021 ◽  
Author(s):  
Peter Hoffmann ◽  
Diana Rechid ◽  
Vanessa Reinhart ◽  
Christina Asmus ◽  
Edouard L. Davin ◽  
...  
Keyword(s):  
Land Use ◽  
High Resolution ◽  
Land Use Change ◽  
Land Cover ◽  
Climate Modeling ◽  
Regional Climate ◽  
Regional Climate Modeling ◽  
Local Scale ◽  
Modeling Studies

<p>Land-use and land cover (LULC) are continuously changing due to environmental changes and anthropogenic activities. Many observational and modeling studies show that LULC changes are important drivers altering land surface feedbacks and land-atmosphere exchange processes that have substantial impact on climate on the regional and local scale. Yet, most long-term regional climate modeling studies do not account for these changes. Therefore, within the WCRP CORDEX Flagship Pilot Study LUCAS (Land Use Change Across Scales) a new workflow was developed to generate high-resolution annual land cover change time series based on past reconstructions and future projections. First, the high-resolution global land cover dataset ESA-CCI LC (~300 m resolution) is aggregated and converted to a 0.1° resolution, fractional plant functional type (PFT) dataset. Second, the land use change information from the land-use harmonized dataset (LUH2), provided at 0.25° resolution as input for CMIP6 experiments, is translated into PFT changes employing a newly developed land use translator (LUT). The new LUT was first applied to the EURO-CORDEX domain. The resulting LULC maps for past and future - the LUCAS LUC dataset - can be applied as land use forcing to the next generation RCM simulations for downscaling CMIP6 by the EURO-CORDEX community and in the framework of FPS LUCAS. The dataset includes land cover and land management practices changes important for the regional and local scale such as urbanization and irrigation. The LUCAS LUC workflow is applied to further CORDEX domains, such as Australasia and North America. The resulting past and future land cover changes will be presented, and challenges regarding the application of the new workflow to different regions will be addressed. In addition, issues related to the implementation of the dataset into different RCMs will be discussed.</p>

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