Abstract. Air pollution, in particular high concentrations of particulate matter smaller than 1 µm diameter (PM1), continues to be a major health problem, and meteorology is known substantially influence atmospheric PM concentrations. However, the scientific understanding ways which complex interactions meteorological factors lead high-pollution episodes inconclusive. In this study, novel, data-driven approach based on empirical relationships used characterize better understand...

Abstract. This paper presents the first investigation of solubility iron in mineral dust aerosols collected at Henties Bay Aerosol Observatory (HBAO), Namibia, from April to December 2017. During study period, 10 intense events occurred. Elemental reached peak concentrations as high 1.5 µg m−3, significantly higher than background levels. These are attributed wind erosion natural soils surrounding gravel plains Namib desert. The composition sampled is found be overall similar that northern...

Abstract Marine low clouds cool the Earth's climate, with their coverage (LCC) being controlled by environment. Here, an observed significant decrease of LCC in northeastern Pacific over past two decades is linked quantitatively to changes cloud‐controlling factors. In a comparison different statistical and machine learning methods, inversion strength near‐surface winds, increase sea surface temperatures (SSTs) are unanimously shown be main causes decrease. While decreased leads more...

Abstract. The role of aerosols, clouds and their interactions with radiation remain among the largest unknowns in climate system. Even though processes involved are complex, aerosol–cloud often analyzed by means bivariate relationships. In this study, 15 years (2001–2015) monthly satellite-retrieved near-global aerosol products combined reanalysis data various meteorological parameters to predict satellite-derived marine liquid-water cloud occurrence properties region-specific artificial...

Abstract. Understanding the processes that determine low-cloud properties and aerosol–cloud interactions (ACIs) is crucial for estimation of their radiative effects. However, covariation meteorology aerosols complicates determination cloud-relevant influences quantification relation. This study identifies analyzes sensitivities cloud fraction droplet effective radius to meteorological aerosol environment in atmospherically stable southeast Atlantic during biomass-burning season based on an...

Abstract. Fog and low clouds (FLCs) are a typical feature along the southwestern African coast, especially in central Namib, where fog constitutes valuable resource of water for many ecosystems. In this study, novel algorithm is presented to detect FLCs over land from geostationary satellite data using only infrared observations. The first its kind as it stationary time thus able reveal detailed view diurnal spatial patterns Namib region. A validation against net radiation measurements...

Abstract. Fog is a defining characteristic of the climate Namib Desert, and its water nutrient input are important for local ecosystems. In part due to sparse observation data, mechanisms that lead fog occurrence in not yet fully understood, date, potential synoptic-scale controls have been investigated. this study, recently established 14-year data set satellite observations low clouds central analyzed conjunction with reanalysis order identify patterns associated low-cloud variability...

Abstract An intensive observation period was conducted in September 2017 the central Namib, Namibia, as part of project Namib Fog Life Cycle Analysis (NaFoLiCA). The purpose field campaign to investigate spatial and temporal patterns coastal fog that occurs regularly during nighttime morning hours. is often linked advection a marine stratus intercepts with terrain up 100 km inland. Meteorological data, including cloud base height, deposition, liquid water path, vertical profiles wind...

Abstract. During the West African summer monsoon season, extended nocturnal stratiform low-level clouds (LLCs) frequently form in atmospheric boundary layer over southern Africa and persist long into following day affecting regional climate. A unique data set was gathered within framework of Dynamics–Aerosol–Chemistry–Cloud Interactions (DACCIWA) project, which allows, for first time, an observational analysis processes parameters crucial LLC formation. In this study, situ remote sensing...

Abstract The quantification of factors leading to harmfully high levels particulate matter (PM) remains challenging. This study presents a novel approach using statistical model that is trained predict hourly concentrations particles smaller than 10 m (PM10) by combining satellite‐borne aerosol optical depth (AOD) with meteorological and land‐use parameters. shown accurately PM10 (overall R = 0.77, RMSE 7.44 g/m ) for measurement sites in Germany. capability satellite observations map...

Abstract. Clouds strongly modulate the top-of-the-atmosphere energy budget and are a major source of uncertainty in climate projections. “Cloud controlling factor” (CCF) analysis derives relationships between large-scale meteorological drivers cloud radiative anomalies, which can be used to constrain feedback. However, choice CCFs is crucial for meaningful constraint. While there rich literature investigating ideal CCF setups low-level clouds, lack analogous research explicitly targeting...

Abstract. In the Namib Desert, fog is only regular water input and, thus, a crucial source for its fauna and flora. Each year, between June October, absorbing biomass burning aerosols (BBAs) overlie stratocumulus clouds in adjacent Southeast Atlantic. some synoptic settings, this layer of BBAs reaches Namibia desert, where it interacts with coastal low (FLCs). study, novel 15-year data set geostationary satellite observations FLC dissipation time Desert used, along reanalysis data, to better...

In this contribution, a statistical model built on observations (ERA5, SEVIRI) is used with climate data from the Coupled Model Intercomparison Project Phase 6 (CMIP6) to estimate cloud-system responses change in Namib desert.Fog, which most relevant non-rainfall water source for plants and animals coastal parts of Desert, may become increasingly important local ecosystems as regional simulations predict warmer drier southern Africa future. However, projecting changes fog using global...

In this study, ground-based remote sensing and in-situ measurements are combined to characterize estimate cloud base height (CBH) development patterns of fog low clouds (FLC). The estimated CBH is further integrated with satellite data map in the Namib Desert for first time.The Desert, characterized by its hyper-arid conditions frequent coverage or level stratus clouds, presents an intriguing environment study low-level their vertical geometry. Understanding dynamics region crucial improving...

One of the main uncertainties in future climate projections is cloud and aerosol contribution to Earth’s radiative budget. The imprecise distinction between these aggregates particles suspension, combined with transition zone within cloud-aerosol continuum, further complicate study their climatic effects. Despite importance, observations (TZ), particularly its vertical distribution, remain limited.This addresses this gap using a Vaisala CL31 ceilometer located at Girona (Spain),...

Abstract This study investigates the impact of air mass origin and dynamics on cloud property changes in Southeast Atlantic (SEA) during biomass burning season. The understanding clouds their determinants at different scales is important for constraining Earth's radiative budget thus prominent climate system research. In this study, thermodynamically stable SEA stratocumulus cover observed not only as result local environmental conditions but also connected to large‐scale meteorology by...

Aerosol–cloud interactions are central to climate system changes and depend on meteorological conditions. This study identifies distinct thermodynamic regimes proposes a conceptual framework for interpreting aerosol effects. In the analysis, ten years (2003–2012) of daily satellite-derived cloud products combined with reanalysis data identify factors controlling Southeast Atlantic stratocumulus microphysics. Considering seasonal influence input from biomass burning, environments that feature...

Air pollution can endanger human health, especially in urban areas. Assessment of air quality primarily relies on ground-based measurements, but these provide only limited information the spatial distribution pollutants. In recent years, satellite derived Aerosol Optical Depth (AOD) has been used to approximate particulate matter (PM) with varying success. this study, relationship between hourly mean concentrations a diameter 10 micrometers or less (PM10) and instantaneous AOD measurements...

Abstract. The radiative effects of clouds make a large contribution to the Earth's energy balance, and changes in constitute dominant source uncertainty global warming response carbon dioxide forcing. To characterize constrain this uncertainty, cloud-controlling factor (CCF) analyses have been suggested that estimate sensitivities large-scale environmental changes, typically cloud-regime-specific multiple linear regression frameworks. Here, local cloud number controlling factors are...

Abstract A better understanding of fog and low stratus (FLS) life cycles, in particular the typical onset dissipation times, can help traffic safety solar power planning. Besides its high dependence on prevalent meteorological conditions, FLS cycle is further determined by type as well underlying geography climate. While satellite‐based data sets with temporal spatial resolution are available, an objective, large‐scale, classification life‐cycle regions, which would allow for more targeted...

Scientific understanding of aerosol-cloud interactions can profit from an analysis the transition regions between pure aerosol and clouds as detected in satellite data. This study identifies evaluates pixels this region by analysing residual areas cloud products Moderate Resolution Imaging Radiometer (MODIS) sensor. These are expected to represent “twilight zone” or zone aerosols clouds. In period (February August, 2007–2011), about 20% all discarded both MODIS retrievals (“Lost Pixels”)....

Abstract. Fog is an essential component of Namib-region ecosystems. Current knowledge on fog patterns and processes limited by a lack coherent observations in space time. In this study, data from multiple satellite platforms station measurements paint picture the spatiotemporal dynamics low cloud (FLC) distribution. It found that observed seasonal FLC derived differ at coastal locations, whereas they agree further inland. This linked to cycle vertical structure FLCs determines probability...

Abstract. This study presents the first detailed observational analysis of complete diurnal cycle stratiform low-level clouds (LLC) and involved atmospheric processes over southern West Africa (SWA). The data used here were collected during comprehensive DACCIWA (Dynamics-Aerosol-Chemistry-Cloud-Interactions in Africa) ground-based campaign, which aimed at monitoring LLC characteristics capturing wide range conditions related to African monsoon flow. In this study, situ remote sensing...

Clouds are one of the major uncertainties climate system. The study cloud processes requires information on physical properties, in particular liquid water path (LWP). This parameter is commonly retrieved from satellite data using look-up table approaches. However, existing LWP retrievals come with related to assumptions inherent retrievals. Here, we present a new retrieval technique for based statistical machine learning model. approach utilizes spectral geostationary channels Meteosat...

Changes in marine boundary layer cloud (MBLC) radiative properties response to aerosol perturbations are largely responsible for uncertainties future climate predictions. In particular, the relationship between droplet number concentration (Nd, a proxy aerosol) and liquid water path (LWP) remains challenging quantify from observations. this study, satellite observations multiple polar-orbiting platforms 2006–2011 used combination with atmospheric reanalysis data regional machine learning...