Search results for " budget"
showing 10 items of 186 documents
Comparison of aircraft measurements during GoAmazon2014/5 and ACRIDICON-CHUVA
2019
Abstract. The indirect effect of atmospheric aerosol particles on the Earth's radiation balance remains one of the most uncertain components affecting climate change throughout the industrial period. The large uncertainty is partly due to the incomplete understanding of aerosol–cloud interactions. One objective of the GoAmazon2014/5 and the ACRIDICON (Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Convective Cloud Systems)-CHUVA (Cloud Processes of the Main Precipitation Systems in Brazil) projects was to understand the influence of emissions from the tropical megacity of Manaus (Brazil) on the surrounding atmospheric environment of the rainforest and to investiga…
West African Monsoon water cycle: 1. A hybrid water budget data set
2010
International audience; This study investigates the West African Monsoon water cycle with the help of a new hybrid water budget data set developed within the framework of the African Monsoon Multidisciplinary Analyses. Surface water and energy fluxes are estimated from an ensemble of land surface model simulations forced with elaborate precipitation and radiation products derived from satellite observations, while precipitable water tendencies are estimated from numerical weather prediction analyses. Vertically integrated atmospheric moisture flux convergence is estimated as a residual. This approach provides an advanced, comprehensive atmospheric water budget, including evapotranspiration,…
Improvements in land surface temperature retrieval from the Landsat series thermal band using water vapor and air temperature
2009
[1] Land surface temperature (LST) is involved in many land surface processes such as evapotranspiration, net radiation, or air temperature modeling. In this paper we present an improved methodology to retrieve LST from Landsat 4 TM, Landsat 5 TM, and Landsat 7 ETM+ using four atmospheric databases covering different water vapor ranges (from 0 to 8 g cm−2) to build the LST retrieval models and using both water vapor and air temperature as input variables. We also compare this with LST retrievals using only water vapor or only air temperature, as well as with an existing LST retrieval algorithm. In order to validate the results, we have selected 77 Landsat images taken between 2002 and 2006 …
Dust emissions over the Sahel associated with the West African monsoon intertropical discontinuity region: A representative case-study
2008
Near-dawn airborne lidar and dropsonde observations acquired on 7 July 2006, during the African Monsoon Multidisciplinary Analysis (AMMA) Special Observing Period 2a1, were used to investigate dust mobilization, lifting and transport in the intertropical discontinuity (ITD) region over western Niger. Atmospheric reflectivity data from the LEANDRE 2 lidar system enabled us to analyse the structure of dust plumes in the context of wind and thermodynamic information provided by the WIND lidar system and dropsondes. Dust mobilization was mainly observed in two locations: (a) within the monsoon flow as the result of the passage of a density current originating from a mesoscale convective system …
Analysis of Desert Dust Outbreaks Over Southern Europe Using CALIOP Data and Ground-Based Measurements
2016
Saharan dust outbreaks are one of the major aerosol sources in Southern Europe. Dust affects the radiative balance of the Earth–atmosphere system and impacts health. The assessment of Saharan outbreaks requires information about the vertical distribution of dust in the atmosphere, usually obtained from lidar measurements, such as the ones performed by the spaceborne Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) sensor. In this paper, we have used CALIOP level-1 daytime data in combination with aerosol optical depth (AOD) measurements from Aerosol Robotic Network (AERONET) ground-based photometers to obtain aerosol profiles during 23 dust outbreaks over Southern Europe. These pro…
Results from the Fourth WMO Filter Radiometer Comparison for aerosol optical depth measurements
2018
Abstract. This study presents the results of the Fourth Filter Radiometer Comparison that was held in Davos, Switzerland, between 28 September and 16 October 2015. Thirty filter radiometers and spectroradiometers from 12 countries participated including reference instruments from global aerosol networks. The absolute differences of all instruments compared to the reference have been based on the World Meteorological Organization (WMO) criterion defined as follows: 95% of the measured data has to be within 0.005 ± 0.001∕m (where m is the air mass). At least 24 out of 29 instruments achieved this goal at both 500 and 865 nm, while 12 out of 17 and 13 out of 21 achieved this at 368 and 412 nm,…
Combinatorial Double Auction Radio Resource Allocation Model in Crowd Networks
2018
International audience; Industrial Partners (IPs) with Mobile Network Operators (MNOs) are extending the mobile network infrastructure with Small Cells (SCs) in order to meet the growing mobile traffic demand. Due to the increasing number of telecommunication market competitors and the scarcity of radio resources, static sharing schemes are no more efficient. New dynamic schemes should be considered to meet both user expectations and economic success. In a crowd networking context, we propose in this work a dynamic radio resource scheme based on combinatorial double auctions. The participants in these auctions are the MNOs considered as buyers and the IPs, providers of SCs, considered as se…
FINANCIAL DEVELOPMENT OPPORTUNITIES OF LATVIA’S SOCIAL SYSTEM AGAINST THE BACKDROP OF CRISIS
2010
Latvian social system is ahead of serious financial problems. The article analyses causes and beginnings of the crisis, in the context of the 1st budget level of social systems in relation to the national budget, as well as the negative impact of the state budget on the social security budget for the financial future. The government also discussed the measures taken by the social system of financial regulation and their impact on society's social environment. Recommendations have been developed for improvement of the situation.
Does politics matter in the conduct of fiscal policy? Political determinants of the fiscal sustainability: Evidence from seven individual Central and…
2007
This paper aims at assessing the fiscal sustainability and its political determinants in seven Central and Eastern European Countries (CEEC), namely Estonia, Latvia, Lithuania, Poland, Slovenia, Slovakia and the Czech Republic. First, using the recent sustainability approach of Bohn (1998) based on fiscal reaction function, econometric findings using Ordinary Least Squares (OLS) reveal a positive response of the primary surplus to changes in debt in several countries. In other words, fiscal policy is sustainable in Baltic countries, Slovenia and Slovakia, but not in Poland and in the Czech Republic. Second, by introducing political dummy variables, we test the electoral budget cycle and the…
US deficit sustainability revisited: A multiple structural change approach
2008
In this article we re-examine the long-run sustainability of US budget deficits, using Bai and Perron's multiple structural change approach. While the deficit would have been weakly sustainable over the full sample (1947:1–2005:3), strong sustainability would appear only between January 1982 and February 1996.