scholarly journals Application of suitable measurement strategies depending on the scales of atmospheric processes

2021 ◽  
Author(s):  
Thomas Foken ◽  
Frank Beyrich ◽  
Volker Wulfmeyer
Keyword(s):  
Remote Sensing ◽  
Measurement Techniques ◽  
Measurement Range ◽  
Careful Consideration ◽  
Atmospheric Measurements ◽  
Horizontal Structure ◽  
Spatial And Temporal Scales ◽  
Range Resolution ◽  
And Performance

<p>The vertical and horizontal structure of the atmosphere and the typical timescales of atmospheric phenomena and processes largely determine the design and performance of atmospheric measurement techniques. Each meteorological process can be characterized by typical spatial and temporal scales. This is based on the spectral organization of atmospheric turbulence and on wavelike processes, where relevant wavelength ranges (spatial dimensions) relate to distinct durations (frequencies). The development of a suitable measurement strategy for any observational task should therefore be based on a careful consideration of the specific processes to be described and resolved. This should govern the decision on, e.g., the measurement range, the measurement levels / range resolution, the horizontal spacing of sensors or sites, the measurement frequencies and averaging times, and sensor characteristics such as response time, resolution, accuracy, sensitivity etc. When using in-situ technologies, a wide variety of measuring platforms can be used, from the classic weather station arrangements, masts, and towers to balloons or controlled airborne platforms (including both manned and remotely piloted aerial vehicles). With remote sensing technology, various measurement systems (both passive and active) are available in terms of measured variables, pointing and scanning options, altitude range, spatial and temporal resolution. It will be shown that the extensive overview tables in the recently published Springer Handbook of Atmospheric Measurements can provide guidance on how in-situ and remote sensing techniques can be optimally used for both routine observations and process studies (field campaigns) for a large variety of applications and how measurement concepts, strategies and networks can be designed.</p>

scholarly journals Accomplishments of the MUSICA project to provide accurate, long-term, global and high-resolution observations of tropospheric {H<sub>2</sub>O,<i>δ</i>D} pairs – a review

2016 ◽  
Vol 9 (7) ◽  
pp. 2845-2875 ◽  
Author(s):  
Matthias Schneider ◽  
Andreas Wiegele ◽  
Sabine Barthlott ◽  
Yenny González ◽  
Emanuel Christner ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Measurement Techniques ◽  
Remote Sensing Data ◽  
Global Scale ◽  
Horizontal Resolution ◽  
Atmospheric Composition ◽  
Remote Sensing Techniques ◽  
Middle Infrared

Abstract. In the lower/middle troposphere, {H2O,δD} pairs are good proxies for moisture pathways; however, their observation, in particular when using remote sensing techniques, is challenging. The project MUSICA (MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water) addresses this challenge by integrating the remote sensing with in situ measurement techniques. The aim is to retrieve calibrated tropospheric {H2O,δD} pairs from the middle infrared spectra measured from ground by FTIR (Fourier transform infrared) spectrometers of the NDACC (Network for the Detection of Atmospheric Composition Change) and the thermal nadir spectra measured by IASI (Infrared Atmospheric Sounding Interferometer) aboard the MetOp satellites. In this paper, we present the final MUSICA products, and discuss the characteristics and potential of the NDACC/FTIR and MetOp/IASI {H2O,δD} data pairs. First, we briefly resume the particularities of an {H2O,δD} pair retrieval. Second, we show that the remote sensing data of the final product version are absolutely calibrated with respect to H2O and δD in situ profile references measured in the subtropics, between 0 and 7 km. Third, we reveal that the {H2O,δD} pair distributions obtained from the different remote sensors are consistent and allow distinct lower/middle tropospheric moisture pathways to be identified in agreement with multi-year in situ references. Fourth, we document the possibilities of the NDACC/FTIR instruments for climatological studies (due to long-term monitoring) and of the MetOp/IASI sensors for observing diurnal signals on a quasi-global scale and with high horizontal resolution. Fifth, we discuss the risk of misinterpreting {H2O,δD} pair distributions due to incomplete processing of the remote sensing products.

scholarly journals A new approach to estimate supersaturation fluctuations in stratocumulus cloud using ground-based remote sensing measurements

2019 ◽  
Author(s):  
Fan Yang ◽  
Robert McGraw ◽  
Edward P. Luke ◽  
Damao Zhang ◽  
Pavlos Kollias ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Steady State ◽  
Cloud Droplet ◽  
In Situ Measurements ◽  
Quasi Steady State ◽  
Marine Stratocumulus ◽  
Spatial And Temporal Scales ◽  
Stratocumulus Clouds ◽  
Condensational Growth

Abstract. Supersaturation, crucial for cloud droplet activation and condensational growth, varies in clouds at different spatial and temporal scales. In-cloud supersaturation is poorly known and rarely measured directly. On the scale of a few tens of meters, supersaturation in clouds has been estimated from in-situ measurements assuming quasi-steady state supersaturation. Here, we provide a new method to estimate supersaturation using ground-based remote sensing measurements, and results are compared with those estimated from aircraft in-situ measurements in a marine stratocumulus cloud during the ACE-ENA field campaign. Our method agrees reasonably well with in-situ estimations and it has three advantages: (1) it does not rely on the quasi-steady state assumption, which is questionable in clean or turbulent clouds; (2) it can provide a supersaturation profile, rather than just point values from in-situ measurements; and (3) it enables building statistics of supersaturation in stratocumulus clouds for various meteorological conditions from multi-year ground-based measurements. The uncertainties, limitations and possible applications of our method are discussed.

scholarly journals Profiling aerosol optical, microphysical and hygroscopic properties in ambient conditions by combining in situ and remote sensing

2017 ◽  
Vol 10 (1) ◽  
pp. 83-107 ◽  
Author(s):  
Alexandra Tsekeri ◽  
Vassilis Amiridis ◽  
Franco Marenco ◽  
Athanasios Nenes ◽  
Eleni Marinou ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Eastern Mediterranean ◽  
Retrieval Algorithm ◽  
Water Volume ◽  
Vertical Profiles ◽  
Hygroscopic Growth ◽  
Ambient Conditions ◽  
Atmospheric Measurements ◽  
Hygroscopic Properties

Abstract. We present the In situ/Remote sensing aerosol Retrieval Algorithm (IRRA) that combines airborne in situ and lidar remote sensing data to retrieve vertical profiles of ambient aerosol optical, microphysical and hygroscopic properties, employing the ISORROPIA II model for acquiring the particle hygroscopic growth. Here we apply the algorithm on data collected from the Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft during the ACEMED campaign in the Eastern Mediterranean. Vertical profiles of aerosol microphysical properties have been derived successfully for an aged smoke plume near the city of Thessaloniki with aerosol optical depth of  ∼  0.4 at 532 nm, single scattering albedos of  ∼  0.9–0.95 at 550 nm and typical lidar ratios for smoke of  ∼  60–80 sr at 532 nm. IRRA retrieves highly hydrated particles above land, with 55 and 80 % water volume content for ambient relative humidity of 80 and 90 %, respectively. The proposed methodology is highly advantageous for aerosol characterization in humid conditions and can find valuable applications in aerosol–cloud interaction schemes. Moreover, it can be used for the validation of active space-borne sensors, as is demonstrated here for the case of CALIPSO.

scholarly journals 1997–2007 CO trend at the high Alpine site Jungfraujoch: a comparison between NDIR surface in situ and FTIR remote sensing observations

2011 ◽  
Vol 11 (13) ◽  
pp. 6735-6748 ◽  
Author(s):  
B. Dils ◽  
J. Cui ◽  
S. Henne ◽  
E. Mahieu ◽  
M. Steinbacher ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Sea Level ◽  
Measurement Techniques ◽  
Surface Concentration ◽  
Infrared Spectrometry ◽  
Research Station ◽  
Strong Impact ◽  
Solar Absorption ◽  
Combining Data

Abstract. Within the atmospheric research community, there is a strong interest in integrated datasets, combining data from several instrumentations. This integration is complicated by the different characteristics of the datasets, inherent to the measurement techniques. Here we have compared two carbon monoxide time series (1997 till 2007) acquired at the high-Alpine research station Jungfraujoch (3580 m above sea level), with two well-established measurement techniques, namely in situ surface concentration measurements using Non-Dispersive Infrared Absorption technology (NDIR), and ground-based remote sensing measurements using solar absorption Fourier Transform Infrared spectrometry (FTIR). The profile information available in the FTIR signal allowed us to extract an independent layer with a top height of 7.18 km above sea level, appropriate for comparison with our in situ measurements. We show that, even if both techniques are able to measure free troposphere CO concentrations, the datasets exhibit marked differences in their overall trends (−3.21 ± 0.03 ppb year−1 for NDIR vs. −0.8 ± 0.4 ppb year−1 for FTIR). Removing measurements that are polluted by uprising boundary layer air has a strong impact on the NDIR trend (now −2.62 ± 0.03 ppb year−1), but its difference with FTIR remains significant. Using the LAGRANTO trajectory model, we show that both measurement techniques are influenced by different source regions and therefore are likely subject to exhibit significant differences in their overall trend behaviour. However the observation that the NDIR-FTIR trend difference is as significant before as after 2001 is at odds with available emission databases which claim a significant Asian CO increase after 2001 only.

scholarly journals 1997–2007 CO trend at the high Alpine site Jungfraujoch: a comparison between NDIR surface in situ and FTIR remote sensing observations

2011 ◽  
Vol 11 (3) ◽  
pp. 8977-9017
Author(s):  
B. Dils ◽  
J. Cui ◽  
S. Henne ◽  
E. Mahieu ◽  
M. Steinbacher ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Measurement Techniques ◽  
Surface Concentration ◽  
Infrared Spectrometry ◽  
Research Station ◽  
Solar Absorption ◽  
Combining Data ◽  
Alpine Research ◽  
Different Characteristics

Abstract. Within the atmospheric research community, there is a strong interest in integrated datasets, combining data from several instrumentations. This integration is complicated by the different characteristics of the datasets, inherent to the measurement techniques. Here we have compared two carbon monoxide time series (1997 till 2007) acquired at the high-Alpine research station Jungfraujoch, with two well-established measurement techniques, namely in situ surface concentration measurements using Non-Dispersive Infrared Absorption technology (NDIR), and ground-based remote sensing measurements using solar absorption Fourier Transform Infrared spectrometry (FTIR). We show that, even if both techniques are able to measure free troposphere CO concentrations, the datasets are influenced by different source regions and therefore are subject to exhibit significant differences in their overall trend behaviour.

scholarly journals The Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI): design, execution, and early results

2011 ◽  
Vol 4 (5) ◽  
pp. 5935-6005 ◽  
Author(s):  
A. J. M. Piters ◽  
K. F. Boersma ◽  
M. Kroon ◽  
J. C. Hains ◽  
M. Van Roozendael ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Nitrogen Dioxide ◽  
Satellite Data ◽  
Measurement Techniques ◽  
Measuring Instruments ◽  
Data Validation ◽  
Data Set ◽  
Early Results ◽  
The World

Abstract. From June to July 2009 more than thirty different in-situ and remote sensing instruments from all over the world participated in the Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI). The campaign took place at KNMI's Cabauw Experimental Site for Atmospheric Research in the Netherlands. Its main objectives were to determine the accuracy of state-of-the-art ground-based measurement techniques for the detection of atmospheric nitrogen dioxide (both in-situ and remote sensing), and to investigate their usability in satellite data validation. The expected outcomes are recommendations regarding the operation and calibration of such instruments, retrieval settings, and observation strategies for the use in ground-based networks for air quality monitoring and satellite data validation. Twenty-four optical spectrometers participated in the campaign, of which twenty-one had the capability to scan different elevation angles consecutively, the so-called Multi-axis DOAS systems, thereby collecting vertical profile information, in particular for nitrogen dioxide and aerosol. Various in-situ samplers simultaneously characterized the variability of atmospheric trace gases and the physical properties of aerosol particles. A large data set of continuous measurements of these atmospheric constituents has been collected under various meteorological conditions and air pollution levels. Together with the permanent measurement capability at the Cabauw site characterizing the meteorological state of the atmosphere, the CINDI campaign provided a comprehensive observational data set of atmospheric constituents in a highly polluted region of the world during summertime. First detailed comparisons performed with the CINDI data show that slant column measurements of NO2, O4 and HCHO with MAX-DOAS agree within 5 to 15%, vertical profiles of NO2 derived from several independent instruments agree within 25%, and MAX-DOAS aerosol optical thickness agrees within 20–30% with AERONET data. For the in-situ NO2 instrument using a molybdenum converter, a bias was found as large as 5 ppbv during day time, when compared to the other in-situ instruments using photolytic converters.

scholarly journals Performance Evaluation of Four Ocean Reflectance Model

2021 ◽  
Vol 13 (14) ◽  
pp. 2748
Author(s):  
Jun Li ◽  
Tongji Li ◽  
Qingjun Song ◽  
Chaofei Ma
Keyword(s):  
Remote Sensing ◽  
Sea Surface ◽  
Concentration Data ◽  
In Situ Data ◽  
Factors Influencing ◽  
Remote Sensing Reflectance ◽  
Reflectance Model ◽  
Main Factors ◽  
And Performance

Phytoplankton are the main factors influencing light under the sea surface in Case Ι water. The ocean reflectance model (ORM), which takes into account the chlorophyll a concentration data, can calculate the remote sensing reflectance of Case Ι water. In this study, we examined the differences and performance of four ORMs, including Morel and Maritorena (2001, MM01), Morel and Gentili (2007, MG07), Mobley (2014, MO14), and Hydrolight Abcase1 Lookup Tables. The differences between the four ORMs in terms of their absorption and backscattering coefficients were evaluated. Preformation of the four ORMs was compared using the NASA bio-Optical Marine Algorithm Dataset and in situ data from the South China Sea. The results showed that preformation of MM01 was the best.

scholarly journals Profiling aerosol optical, microphysical and hygroscopic properties in ambient conditions by combining in-situ and remote sensing

2016 ◽  
Author(s):  
Alexandra Tsekeri ◽  
Vassilis Amiridis ◽  
Franco Marenco ◽  
Athanasios Nenes ◽  
Eleni Marinou ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Eastern Mediterranean ◽  
Retrieval Algorithm ◽  
Water Volume ◽  
Aerosol Layer ◽  
Vertical Profiles ◽  
Atmospheric Measurements ◽  
Hygroscopic Properties ◽  
532 Nm

Abstract. We present the In-situ/Remote sensing aerosol Retrieval Algorithm (IRRA) that combines airborne in-situ and lidar remote sensing data to retrieve vertical profiles of ambient aerosol optical, microphysical and hygroscopic properties, employing the ISORROPIA II model for acquiring the hygroscopic growth. Here we apply the algorithm on data collected from the Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft during the ACEMED campaign in Eastern Mediterranean: vertical profiles of aerosol microphysical properties have been derived successfully for an aged smoke plume near the city of Thessaloniki with typical lidar ratios of ~ 60–80 sr at 532 nm, along with single scattering albedos of ~ 0.9–0.95 at 550 nm. The aerosol layer reaches the 3.5 km with aerosol optical depth at ~ 0.4 at 532 nm. Our analysis shows that the smoke particles are highly hydrated above land, with 55 % and 80 % water volume content for ambient relative humidity of 80 % and 90 %, respectively. The proposed methodology is highly advantageous for aerosol characterization in humid conditions and can find valuable applications in aerosol-cloud interaction schemes. Moreover, it can be used for the validation of active space-borne sensors, as is demonstrated here for the case of CALIPSO.

scholarly journals TOWARDS AN INTEGRATED EARTH OBSERVATION SCIENCE IN A BIG EARTH DATA ERA

2020 ◽  
Vol XLII-3/W10 ◽  
pp. 63-66
Author(s):  
T. Blaschke
Keyword(s):  
Remote Sensing ◽  
Data Science ◽  
World View ◽  
Spatial Scales ◽  
Earth Observation ◽  
Gis And Remote Sensing ◽  
Spatial And Temporal Scales ◽  
Wide Range ◽  
Abrupt Changes

Abstract. Earth observation (EO) data – including satellite-borne, airborne or drone-based imagery – have become indispensable for the monitoring of the environment. EO supports tackling the ‘grand challenges’ at global spatial scales, such as global change and climate variability technology but also retail or insurance. Like a macroscope, it opens research avenues to observe processes occurring over a wide range of spatial and temporal scales, from abrupt changes such as earthquakes, to decadal shifts such as growth and shrinkage of ice sheets. Particularly satellite data became a success story and empowered individuals, businesses and society. Until a few years ago, the term remote sensing mainly stood for a digital raster world view while the GIS community was inclined to the vector world. “Earth Observation” seems to be integrative and to accommodate various means of data acquisition from satellites, aircrafts, drones, to in situ measurements. Today the rapid growth of data science, the consumerization of GIS and remote sensing, and the continued spread of online cartographic tools are prompting a more holistic Earth Observation Science and interdisciplinary educational programmes.

Sign in / Sign up

Export Citation Format

Share Document