Impact of assimilating spaceborne lidar dust extinction in Northern Africa and Middle East

An advanced dust reanalysis with high spatial (at 10km x 10km) and temporal resolution is produced in the framework of DustClim project (Dust Storms Assessment for the development of user-oriented Climate Services in Northern Africa, Middle East and Europe) [1], aiming to provide reliable information on dust storms current conditions and predictions, focusing on the dust impacts on various socio-economic sectors.This regional reanalysis is based on the assimilation of dust-related satellite observations from MODIS instrument [2], in the Multiscale Online Nonhydrostatic Atmosphere Chemistry model (NMMB-MONARCH) [3], over the region of Northern Africa, Middle East and Europe. The reanalysis is now available for a seven-year period (2011-2016) providing the following dust products: Columnar and surface concentration, distributed in 8 dust particle size bins, with effective radius ranging from 0,15&#956;m to 7,1&#956;m, dust load, dry and wet dust deposition, dust optical depth (DOD) and coarse dust optical depth (radius>1&#956;m) at 550nm and profiles of dust extinction coefficient at 550nm.A thorough evaluation of the reanalysis is in progress to assess the quality and uncertainty of the dust simulations, using dust-filtered products, retrieved from different measurement techniques, both from in-situ and remote sensing observations. The datasets considered for the DustClim reanalysis evaluation, provide observations of variables that are included in the model simulations. The DOD is provided by AERONET network [4] and by IASI [5], POLDER [6], MISR [7] and MODIS space-borne sensors; Dust extinction profiles are provided by ACTRIS/EARLINET network [8] and CALIPSO/LIVAS dataset [9]; Dust PM10 surface concentrations derived from INDAAF/SDT [10] network and estimated from PM10 measurements [11] performed within EEA/EIONET [12] network; Dust deposition measurements collected by the INDAAF/SDT and the CARAGA/DEMO [13] networks; Dust size distribution from in situ observations (ground-based and airborne); And column-averaged dust size distribution at selected stations from the AERONET network.In this work, we present the results of the model evaluation for the year 2012. The first evaluation results will focus on dust extinction coefficient profiles from EARLINET and LIVAS, on DOD using AERONET, MISR and MODIS datasets, and on dust PM10 concentration from INDAAF/SDT network. Moreover, a DOD climatology covering the whole reanalysis period (2011-2016) will be compared with the results obtained from AERONET network.&#160;References[1] https://sds-was.aemet.es/projects-research/dustclim[2] https://modis.gsfc.nasa.gov/[3] Di Tomaso et al., Geosci. Model Dev., 10, 1107-1129, doi:10.5194/gmd-10-1107-2017., 2017.[4] https://aeronet.gsfc.nasa.gov/[5] Cuesta et al., J. Geophys. Res., 120, 7099-7127, 2015.[6] http://www.icare.univ-lille1.fr/parasol/overview/[7] https://misr.jpl.nasa.gov/[8] https://www.earlinet.org/[9] Marinou et al., Atmos. Chem. Phys., 17, 5893&#8211;5919, https://doi.org/10.5194/acp-17-5893-2017, 2017.[10] https://indaaf.obs-mip.fr/[11] Barnaba et al., Atmospheric environment, 161, 288-305, 2017.[12] https://www.eionet.europa.eu/[13] Laurent et al., Atmos. Meas. Tech., 8, 2801&#8211;2811, 2015.&#160;&#160;AcknowledgementDustClim project is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union (Grant 690462).

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A 3-D evaluation of the MACC reanalysis dust product over Europe, Northern Africa and Middle East using CALIOP/CALIPSO dust satellite observations

10.5194/acp-2017-1238 ◽

2018 ◽

Author(s):

Aristeidis K. Georgoulias ◽

Athanasios Tsikerdekis ◽

Vassilis Amiridis ◽

Eleni Marinou ◽

Angela Benedetti ◽

...

Keyword(s):

Middle East ◽

Extinction Coefficient ◽

Northern Africa ◽

Sea Salt ◽

Profile Data ◽

Dust Extinction ◽

Dust Sources ◽

Layer 4 ◽

High Dust ◽

Natural Aerosol

Abstract. The MACC reanalysis dust product is evaluated over Europe, Northern Africa and Middle East using the EARLINET-optimized CALIOP/CALIPSO pure dust satellite-based product LIVAS (2007–2012). MACC dust optical depth at 550 nm (DOD550) data are compared against LIVAS DOD532 observations. As only natural aerosol (dust and sea salt) profiles are available in MACC, here we focus on layers above 1 km a.s.l. to diminish the influence of sea salt particles that typically reside at low heights. So, MACC natural aerosol extinction coefficient profiles at 550 nm are compared against dust extinction coefficient profiles at 532 nm from LIVAS assuming that the MACC natural aerosol profile data can be similar to the dust profile data, especially over pure continental regions. It is shown that the reanalysis data are capable of capturing the major dust hot spots in the area as the MACC DOD550 patterns are close to the LIVAS DOD532 patterns throughout the year. MACC overestimates DOD for regions with low dust loadings and underestimates DOD for regions with high dust loadings where DOD exceeds ~ 0.3. The mean bias between the MACC and LIVAS DOD is 0.025 (~ 25 %) over the whole domain. Both MACC and LIVAS capture the summer and spring high dust loadings, especially over Northern Africa and Middle East, and exhibit similar monthly structures despite the biases. In this study, dust extinction coefficient patterns are reported at four layers (layer 1: 1200–3000 m a.s.l., layer 2: 3000–4800 m a.s.l., layer 3: 4800–6600 m a.s.l. and layer 4: 6600–8400 m a.s.l.). The MACC and LIVAS extinction coefficient patterns are similar over areas characterized by high dust loadings for the first 3 layers. Within layer 4, MACC overestimates extinction coefficients consistently throughout the year over the whole domain. MACC overestimates extinction coefficients compared to LIVAS over regions away from the major dust sources while over regions close to the dust sources (Sahara and Middle East) underestimates strongly only for heights below ~ 3–5 km a.s.l. depending on the period of the year. In general, it is shown that dust loadings appear over remote regions and at heights up to 9 km a.s.l. in MACC contrary to LIVAS. This could be due to the model performance and parameterizations of emissions and other processes, due to the assimilation of satellite aerosol measurements over dark surfaces only or due to a possible enhancement of aerosols by the MACC assimilation system.

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A 3-D evaluation of the MACC reanalysis dust product over Europe, northern Africa and Middle East using CALIOP/CALIPSO dust satellite observations

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-8601-2018 ◽

2018 ◽

Vol 18 (12) ◽

pp. 8601-8620 ◽

Cited By ~ 8

Author(s):

Aristeidis K. Georgoulias ◽

Athanasios Tsikerdekis ◽

Vassilis Amiridis ◽

Eleni Marinou ◽

Angela Benedetti ◽

...

Keyword(s):

Middle East ◽

Extinction Coefficient ◽

Northern Africa ◽

Sea Salt ◽

Profile Data ◽

Dust Extinction ◽

Dust Sources ◽

Layer 4 ◽

High Dust ◽

Natural Aerosol

Abstract. The MACC reanalysis dust product is evaluated over Europe, northern Africa and the Middle East using the EARLINET-optimized CALIOP/CALIPSO pure dust satellite-based product LIVAS (2007–2012). MACC dust optical depth at 550 nm (DOD550) data are compared against LIVAS DOD532 observations. As only natural aerosol (dust and sea salt) profiles are available in MACC, here we focus on layers above 1 km a.s.l. to diminish the influence of sea salt particles that typically reside at low heights. So, MACC natural aerosol extinction coefficient profiles at 550 nm are compared against dust extinction coefficient profiles at 532 nm from LIVAS, assuming that the MACC natural aerosol profile data can be similar to the dust profile data, especially over pure continental regions. It is shown that the reanalysis data are capable of capturing the major dust hot spots in the area as the MACC DOD550 patterns are close to the LIVAS DOD532 patterns throughout the year. MACC overestimates DOD for regions with low dust loadings and underestimates DOD for regions with high dust loadings where DOD exceeds ∼ 0.3. The mean bias between the MACC and LIVAS DOD is 0.025 (∼ 25 %) over the whole domain. Both MACC and LIVAS capture the summer and spring high dust loadings, especially over northern Africa and the Middle East, and exhibit similar monthly structures despite the biases. In this study, dust extinction coefficient patterns are reported at four layers (layer 1: 1200–3000 m a.s.l., layer 2: 3000–4800 m a.s.l., layer 3: 4800–6600 m a.s.l. and layer 4: 6600–8400 m a.s.l.). The MACC and LIVAS extinction coefficient patterns are similar over areas characterized by high dust loadings for the first three layers. Within layer 4, MACC overestimates extinction coefficients consistently throughout the year over the whole domain. MACC overestimates extinction coefficients compared to LIVAS over regions away from the major dust sources while over regions close to the dust sources (the Sahara and Middle East) it underestimates strongly only for heights below ∼ 3–5 km a.s.l. depending on the period of the year. In general, it is shown that dust loadings appear over remote regions and at heights up to 9 km a.s.l. in MACC contrary to LIVAS. This could be due to the model performance and parameterizations of emissions and other processes, due to the assimilation of satellite aerosol measurements over dark surfaces only or due to a possible enhancement of aerosols by the MACC assimilation system.

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May Measurement Month 2017: an analysis of blood pressure screening results from the United Arab Emirates—Northern Africa and Middle East

European Heart Journal Supplements ◽

10.1093/eurheartj/suz074 ◽

2019 ◽

Vol 21 (Supplement_D) ◽

pp. D118-D120 ◽

Cited By ~ 1

Author(s):

Afzalhussein Yusufali ◽

Nooshin Bazargani ◽

Amrish Agrawal ◽

Khalifa Muhammed ◽

Hanan Obaid ◽

...

Keyword(s):

Blood Pressure ◽

Middle East ◽

United Arab Emirates ◽

Northern Africa ◽

Blood Pressure Screening

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Events in Northern Africa and Middle East: Causes and Consequences

World Economy and International Relations ◽

10.20542/0131-2227-2011-7-11-25 ◽

2011 ◽

pp. 11-25

Author(s):

I. Labinskaya

Keyword(s):

Middle East ◽

North Africa ◽

Large Scale ◽

Arab Countries ◽

Northern Africa ◽

External Factors ◽

Wide Range ◽

The Usa ◽

Oriental Studies

Political developments in North Africa and the Middle East that have begun in January 2011 are gaining strength and involve an increasing number of Arab countries. The participants of the Roundtable – experts from IMEMO, Institute of Oriental Studies (RAS), Institute of the USA and Canada (RAS) and Mrs. E. Suponina from “Moscow News” newspaper analyzed a wide range of issues associated with these events. Among them are: 1) the reasons for such a large-scale explosion, 2) the nature of the discussed developments (revolutions, riots?) and who are the subjects of the current “Arab drama”, 3) the role of Islam and political Islamism, 4) the role of external factors.

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Events in Northern Africa and Middle East: Causes and Consequences (the end)

World Economy and International Relations ◽

10.20542/0131-2227-2011-8-52-66 ◽

2011 ◽

pp. 52-66

Author(s):

I. Labinskaya

Keyword(s):

Middle East ◽

North Africa ◽

Northern Africa ◽

External Factors ◽

Protest Movements ◽

Research Institutes ◽

Internal And External Factors

A discussion of the developments in North Africa and Middle East by a group of experts from three research institutes and the newspaper “Moscow news” is continued. It has begun in the previous of the magazine. Now, an attempt is made to identify possible scenarios of further developments, as well as the roles of the various actors, including protest movements. Internal and external factors of what is happening in these regions are classified.

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China and the Revolutions in the Middle East and North Africa

Middle East Law and Governance ◽

10.1163/187633711x591549 ◽

2011 ◽

Vol 3 (1-2) ◽

pp. 192-203 ◽

Cited By ~ 2

Author(s):

Randall Peerenboom

Keyword(s):

Social Justice ◽

Middle East ◽

North Africa ◽

Authoritarian Regimes ◽

Northern Africa ◽

Mena Countries ◽

Turn On ◽

Potential Sources ◽

The Government

The 2011 revolutions in the Middle East and Northern Africa (MENA) led to considerable hope for some people that China would experience a similar political uprising, as well as considerable anxiety for the ruling regime. The government’s immediate response was to downplay the risk of a similar event occurring in China by distinguishing between China and MENA, while at the same time cracking down on activists and other potential sources of instability—including attempts to organize popular revolutionary protests in China. Although the government has so far managed to avoid a similar uprising, neither response has been entirely successful. Despite a number of significant diff erences between China and MENA countries, there are enough commonalities to justify concerns about political instability. Moreover, relying on repression alone is not a long-term solution to the justified demands of Chinese citizens for political reforms and social justice. Whether China will ultimately be able to avoid the fate of authoritarian regimes in MENA countries will turn on its ability to overcome a series of structural challenges while preventing sudden and unpredictable events, like those that gave rise to the Arab revolutions, from spinning out of control.

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A reanalysis-based study of desert dust in Northern Africa, the Middle East and Europe in a recent decade

10.7185/gold2021.7588 ◽

2021 ◽

Author(s):

Enza Di Tomaso ◽

Jerónimo Escribano ◽

Paul Ginoux ◽

Sara Basart ◽

Francesca Macchia ◽

...

Keyword(s):

Middle East ◽

Recent Decade ◽

Northern Africa ◽

Desert Dust

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A 10-year regional reanalysis of desert dust aerosol at high spatial resolution

10.5194/egusphere-egu21-11644 ◽

2021 ◽

Author(s):

Enza Di Tomaso ◽

Jerónimo Escribano ◽

Paul Ginoux ◽

Sara Basart ◽

Francesca Macchia ◽

...

Keyword(s):

Middle East ◽

Data Assimilation ◽

Spatial Resolution ◽

Weather Prediction ◽

Reanalysis Data ◽

Northern Africa ◽

Dust Aerosol ◽

Data Set ◽

Desert Dust ◽

Deep Blue

Desert dust is the most abundant aerosol by mass residing in the atmosphere. It plays a key role in the Earth&#8217;s system by influencing the radiation balance, by affecting cloud formation and cloud chemistry, and by acting as a fertilizer for the growth of phytoplankton and for soil through its deposition over the ocean and land.Due to the nature of its emission and transport, atmospheric dust concentrations are highly variable in space and time and, therefore, require a continuous monitoring by measurements. Dust observations are best exploited by being combined with model simulations for the production of analyses and reanalyses, i.e., complete and consistent four dimensional reconstructions of the atmosphere. Existing aerosol (and dust) reanalyses for the global domain have been produced by total aerosol constraint and at relatively coarse spatial resolution, while regional reanalyses exclude some of the regions containing the major sources of desert dust in Northern Africa and the Middle East.We present here a 10-year reanalysis data set of desert dust at a horizontal resolution of 0.1&#176;, and which covers the domain of Northern Africa, the Middle East and Europe. The reanalysis has been produced by assimilating in the MONARCH chemical weather prediction system (Di Tomaso et al., 2017) satellite retrievals over dust source regions with specific dust observational constraint (Ginoux et al., 2012; Pu and Ginoux, 2016).Furthermore, we describe its evaluation in terms of data assimilation diagnostics and comparison against independent observations. Statistics of analysis departures from assimilated observations prove the consistency of the data assimilation system showing that the analysis is closer to the observations than the first-guess. Temporal mean of analysis increments show that the assimilation led to an overall reduction of dust with pattern of systematic corrections that vary with the seasons, and can be linked primarily to misrepresentation of source strength.Independent evaluation of the analysis with AERONET observations indicates that the reanalysis data set is highly accurate, and provides therefore a reliable historical record of atmospheric desert dust concentrations in a recent decade.ReferencesDi Tomaso, E., Schutgens, N. A. J., Jorba, O., and P&#233;rez Garc&#237;a-Pando, C. (2017): Assimilation of MODIS Dark Target and Deep Blue observations in the dust aerosol component of NMMB-MONARCH version 1.0, Geosci. Model Dev., 10, 1107-1129.Ginoux, P., Prospero, J. M., Gill, T. E., Hsu, N. C. and Zhao, M. (2012): Global-Scale Attribution of Anthropogenic and Natural Dust Sources and Their Emission Rates Based on Modis Deep Blue Aerosol Products. Rev Geophys 50.Pu, B., and Ginoux, P. (2016). The impact of the Pacific Decadal Oscillation on springtime dust activity in Syria. Atmospheric Chemistry and Physics, 16(21), 13431-13448.Acknowledgements The authors acknowledge the DustClim project which is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union (435690462); PRACE (eDUST/eFRAGMENT1/eFRAGMENT2), RES (AECT-2020-3-0013/AECT-2019-3-0001/AECT-2020-1-0007) for awarding access to MareNostrum at BSC and for technical support.

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Thermal infrared remote sensing of mineral dust over land and ocean: a spectral SVD based retrieval approach for IASI

Atmospheric Measurement Techniques ◽

10.5194/amt-4-757-2011 ◽

2011 ◽

Vol 4 (5) ◽

pp. 757-773 ◽

Cited By ~ 47

Author(s):

L. Klüser ◽

D. Martynenko ◽

T. Holzer-Popp

Keyword(s):

Particle Size ◽

Dust Particle ◽

Mineral Dust ◽

A Priori ◽

Thermal Infrared ◽

Effective Radius ◽

Northern Africa ◽

Lookup Table ◽

Dust Extinction ◽

Dust Events

Abstract. From the high spectral resolution thermal infrared observations of the Infrared Atmospheric Sounding Interferometer (IASI) mineral dust AOD (transferred from thermal infrared to 0.5 μm) is retrieved using a Singular Vector Decomposition of brightness temperature spectra. As infrared retrieval based on 8–12 μm observations, dust observation with IASI is independent from solar illumination. Through the linear combinations of suitable independent singular vectors weighted by their contribution to the observed signal, and a projection of different a-priori dust spectra on the resulting signal the dust can be well distinguished from the influence of surface emissivity and gas absorption. In contrast to lookup-table based single-channel retrievals this method takes advantage of the spectral shape of dust extinction and surface and atmosphere influence over the total 8–12 μm window band. Using different a-priori spectra for dust extinction allows also for an estimation of dust particle size in terms of effective radius based on the respective dust model size distributions. These dust models are also used for the transfer of infrared AOD to 0.5 μm. Four months of IASI observations covering Northern Africa and Arabia are used for evaluation. Two large scale dust events, one covering the Arabian Peninsula and adjacent parts of the Indian Ocean, the other over the Atlantic Ocean off the coast of West-Africa, are analysed and compared with other satellite images. They also show the good suitability of IASI data for dust observation at day and night. Monthly means derived from IASI observations represent well the known seasonal cycles of dust activity over Northern Africa and Arabia. IASI Dust AOD0.5 μm and AERONET coarse mode AOD0.5 μm are reasonably well (linearly) correlated with ρ=0.623. Moreover, comparison of time series of AERONET and IASI observations shows that the evolution of dust events is very well covered by the IASI observations. Rank correlation between dust effective radius and AERONET Ångström exponent is −0.557 indicating the general capability of (qualitative) dust particle size information being provided by this method.

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