Pradeebane Vaittinada AyarLaboratoire des Sciences du Climat et l'Environnement | LSCE
Pradeebane Vaittinada Ayar
PhD
About
31
Publications
5,502
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405
Citations
Introduction
Additional affiliations
October 2018 - August 2020
Position
- PostDoc Position
Description
- Review of culvert design criteria for 25 km2 and less drainage catchments in a climate change context in collaboration with Quebec province ministry of transportation. Characterisation of wet and dry persistence at daily and hourly time-scale in Québec and the North-East of the North American continent.
October 2016 - September 2018
Institut des Géosciences de l’Environnement
Position
- PostDoc Position
Description
- Development of a spatial rainfall simulator over mountainous catchments at daily time scale and one km² spatial resolution for EDF (the French electricity company).
Education
February 2013 - January 2016
October 2010 - September 2011
September 2007 - September 2010
Publications
Publications (31)
Backgrounds: The worldwide population is ageing. Biological sex is first and foremost a genetic modifier of disease. To prevent self-arm many techniques can be used in older patients. Among them coercive measure consisting of physical restraint (PR) is one of the techniques. This study aims to assess the effects of the biological sex on the long-te...
The inter-annual variability of global ocean air-sea CO2 fluxes are non-negligible, modulates the global warming signal, and yet it is poorly represented in Earth System Models (ESMs). ESMs are highly sophisticated and computationally demanding, making it challenging to perform dedicated experiments to investigate the key drivers of the CO2 flux va...
El Niño-Southern Oscillation (ENSO) flavors in the tropical Pacific are studied from a regime perspective. Five recurring spatial patterns or regimes characterizing the diversity of ENSO are established using a clustering approach applied to the HadISST sea surface temperature (SST) anomalies. Compared to previous studies, our approach gives a mont...
Background
Electrocardiogram (ECG) is one of the most commonly performed examinations in emergency medicine. The literature suggests that one-third of ECG interpretations contain errors and can lead to clinical adverse outcomes. The purpose of this study was to assess the quality of real-time ECG interpretation by senior emergency physicians compar...
The seasonal cycle is the dominant mode of variability in the air‐sea CO2 flux in most regions of the global ocean, yet discrepancies between different seasonality estimates are rather large. As part of the Regional Carbon Cycle Assessment and Processes Phase 2 project (RECCAP2), we synthesize surface ocean pCO2 and air‐sea CO2 flux seasonality fro...
The seasonal cycle is the dominant mode of variability in the air-sea CO2 flux in most regions of the global ocean, yet discrepancies between different seasonality estimates are rather large. As part of the Regional Carbon Cycle Assessment and Processes phase 2 project (RECCAP2), we synthesize surface ocean pCO2 and air-sea CO2 flux seasonality fro...
Supplementary material to the "Space-time simulation of precipitation based on weather pattern sub-sampling and meta-Gaussian model" paper
El Niño Southern Oscillation (ENSO) flavours in the tropical Pacific are studied from a regime perspective. Five recurring spatial patterns or regimes characterising the diversity of ENSO are established using a clustering approach applied to the HadISST sea surface temperature anomalies (SSTA). Two warm (eastern and central El Niño), two cold (bas...
The interannual variability of the air-sea CO2 flux is non-negligible, modulates the global warming signal, and yet it is poorly represented in Earth System Models (ESMs). ESMs are highly sophisticated and computationally demanding, making it challenging to perform dedicated experiments to investigate the key drivers of the CO2 flux variability acr...
The El Niño–Southern Oscillation (ENSO) widely modulates the global carbon cycle. More specifically, it alters the net uptake of carbon in the tropical ocean. Indeed, over the tropical Pacific less carbon is released by oceans during El Niño, while the opposite is the case for La Niña. Here, the skill of Earth system models (ESMs) from the latest C...
The El Niño Southern Oscillation (ENSO) widely modulates the global carbon cycle, in particular, by altering the net uptake of carbon in the tropical ocean. Indeed, over the tropics less carbon is released by oceans during El Niño while it is the opposite for La Niña. Here, the skill of Earth System Models (ESM) from the latest Coupled Model Interc...
Purpose
Identified factors associated with multiple emergency department (ED) visits (≥) for asthma, which is associated with death.
Patients and Methods
We first conducted a qualitative study. We invited French-speaking adults (≥18 years old) with a diagnosis of asthma for more than 6 months. The identified concepts were transcribed into items. A...
European climate variability is shaped by atmospheric dynamics over the North Atlantic and local processes. Better understanding their future seasonality is essential to anticipate changes in weather conditions for human and natural systems. We explore atmospheric seasonality over 1979–2017 and 1979–2100 with seasonal circulation regimes (SCRs), by...
The El Niño–Southern Oscillation (ENSO) widely modulates the global carbon cycle. More specifically, it alters the net uptake of carbon in the tropical ocean. Indeed, over the tropical Pacific less carbon is released by oceans during El Niño, while the opposite is the case for La Niña. Here, the skill of Earth system models (ESMs) from the latest C...
Risks associated to extreme hydrological conditions, such as floods and droughts, are expected to increase in future climate because of projected changes in precipitation and temperature. Assessing how wet and dry persisting conditions (or spells) will evolve in future climate is a crucial step in the study of extreme hydrological events. Projected...
Climate simulations often need to be adjusted (i.e., corrected) before any climate change impacts studies. However usual bias correction approaches do not differentiate the bias from the different uncertainties of the climate simulations: scenario uncertainty, model uncertainty and internal variability. In particular, in the case of a multi-run ens...
We investigate North Atlantic weather seasonality over 1979–2100 by classifying year-round fields of 500 hPa geopotential height from one reanalysis dataset and 12 climate models. Generally, models have seasonal structures similar to the reanalyses. Historical winter (summer) conditions decrease (increase), due to uniform Z500 increase (i.e. unifor...
Simulation methods for design flood estimations in dam safety studies require fine scale precipitation data to provide quality input for hydrological models, especially for extrapolation to extreme events. This leads to use statistical models such as stochastic weather generators. The aim here is to develop a stochastic model adaptable on mountaino...
Distributed application of the SCHADEX method. Application to the Ardèche catchment.
We propose an objective framework for selecting rainfall hazard mapping models in a region starting from rain gauge data. Our methodology is based on the evaluation of several goodness-of-fit scores at regional scale in a cross-validation framework, allowing us to assess the goodness-of-fit of the rainfall cumulative distribution functions within t...
MEthane Remote LIdar missioN (MERLIN) is a German-French space mission, scheduled for launch in 2024 and built around an innovative light detecting and ranging instrument that will retrieve methane atmospheric weighted columns. MERLIN products will be assimilated into chemistry transport models to infer methane emissions and sinks. Here the expecte...
We propose an objective framework for estimating rainfall cumulative distribution function within a region when data are only available at rain gauges. Our methodology is based on the evaluation of several goodness-of-fit scores in a cross-validation framework, allowing to assess goodness-of-fit of the full distribution but with a particular focus...
Statistical downscaling models (SDMs) and bias correction (BC) methods are commonly used to provide regional or debiased climate projections. However, most SDMs belong to the “perfect prognosis” context, meaning that they are calibrated on reanalysis predictors before being applied to GCM simulations. If the latter are biased, SDMs might suffer fro...
This paper analyzes the sensitivity of a hydrological model to different methods to statistically downscale climate precipitation and temperature over four western Mediterranean basins illustrative of different hydrometeorological situations. The comparison was conducted over a common 20-year period (1986–2005) to capture different climatic conditi...
The study of climate variability is vital in order to understand and anticipate the consequences of future climate changes. Large data sets generated by general circulation models (GCMs) are currently available and enable us to conduct studies in that direction. However, these models resolve only partially the interactions between climate and human...
This paper analyzes the sensitivity of a hydrological model to different methods to statistically downscale climate precipitation and temperature over four western Mediterranean basins illustrative of different hydro-meteorological situations. The comparison was conducted over a common 20 year period (1986–2005) to capture different climatic condit...
Given the coarse spatial resolution of General Circulation Models, finer scale projections of variables affected by local-scale processes such as precipitation are often needed to drive impacts models, for example in hydrology or ecology among other fields. This need for high-resolution data leads to apply projection techniques called downscaling....
Seasons and seasonality are the main properties of extra‐tropical climate that affect ecosystems and society. For example, agriculture, tourism, energy consumption or ecosystem phenology are primarily dependent on seasonality and on the magnitude of the meteorological events associated within each season. Changes in the seasonality of variables lik...