In situ water vapour measurement, and a case study of the drying mechanism of the tropical lower stratosphere

Abstract. High-resolution in situ balloon measurements of water vapour, aerosol, methane and temperature in the upper tropical tropopause layer (TTL) and lower stratosphere are used to evaluate the processes affecting the stratospheric water budget: horizontal transport (in-mixing) and hydration by cross-tropopause overshooting updrafts. The obtained in situ evidence of these phenomena are analysed using satellite observations by Aura MLS (Microwave Limb Sounder) and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) together with trajectory and transport modelling performed using CLaMS (Chemical Lagrangian Model of the Stratosphere) and HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model. Balloon soundings were conducted during March 2012 in Bauru, Brazil (22.3° S) in the frame of the TRO-Pico campaign for studying the impact of convective overshooting on the stratospheric water budget. The balloon payloads included two stratospheric hygrometers: FLASH-B (Fluorescence Lyman-Alpha Stratospheric Hygrometer for Balloon) and Pico-SDLA instrument as well as COBALD (Compact Optical Backscatter Aerosol Detector) sondes, complemented by Vaisala RS92 radiosondes. Water vapour vertical profiles obtained independently by the two stratospheric hygrometers are in excellent agreement, ensuring credibility of the vertical structures observed. A signature of in-mixing is inferred from a series of vertical profiles, showing coincident enhancements in water vapour (of up to 0.5 ppmv) and aerosol at the 425 K (18.5 km) level. Trajectory analysis unambiguously links these features to intrusions from the Southern Hemisphere extratropical stratosphere, containing more water and aerosol, as demonstrated by MLS and CALIPSO global observations. The in-mixing is successfully reproduced by CLaMS simulations, showing a relatively moist filament extending to 20° S. A signature of local cross-tropopause transport of water is observed in a particular sounding, performed on a convective day and revealing water vapour enhancements of up to 0.6 ppmv as high as the 404 K (17.8 km) level. These are shown to originate from convective overshoots upwind detected by an S-band weather radar operating locally in Bauru. The accurate in situ observations uncover two independent moisture pathways into the tropical lower stratosphere, which are hardly detectable by space-borne sounders. We argue that the moistening by horizontal transport is limited by the weak meridional gradients of water, whereas the fast convective cross-tropopause transport, largely missed by global models, can have a substantial effect, at least at a regional scale.

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Ozone variability and trends in the UTLS derived from the IAGOS- CARIBIC observatory using JETPAC

10.5194/egusphere-egu2020-7734 ◽

2020 ◽

Author(s):

Harald Boenisch ◽

Andreas Zahn ◽

Luis Millan

Keyword(s):

Water Vapour ◽

Lower Stratosphere ◽

In Situ Measurements ◽

Research Infrastructure ◽

European Research ◽

Coordinate Systems ◽

Upper Troposphere ◽

Work In Progress

The CARIBIC (Civil &#160;Aircraft &#160;for &#160;the &#160;Regular &#160;Investigation &#160;of the atmosphere Based on an&#160; Instrumented Container) project is part of the a European research infrastructure IAGOS (In- Service Aircraft for a Global Observing System) making regular in-situ measurements of more&#160; than 100 atmospheric constituents, include ozone and water vapour, on-board of an in-service&#160; passenger &#160;aircraft &#160;operated &#160;by &#160;Lufthansa. &#160;The &#160;dataset &#160;of &#160;the &#160;IAGOS-CARIBIC &#160;is &#160;therefore&#160; ideally suited as a testbed for the SPARC (Stratosphere-troposphere Processes And their Role&#160; in Climate) activity OCTAV-UTLS (Observed Composition Trends And Variability in the Upper&#160; Troposphere and Lower Stratosphere). One key aspect, shown here as work in progress, is to&#160; develop, define and apply common metrics for the comparison of different UTLS datasets&#160; using a variety of meteorological coordinate systems derived from reanalysis datasets. The&#160; focus here is on the variability of ozone in the upper troposphere and lower stratosphere&#160; (UTLS) on interannual and seasonal timescales and the observed trends. The in-situ ozone&#160; measurements by IAGOS-CARIBIC are analysed relative to different tropopause definitions&#160; and coordinate systems. All these meteorological information applied here are produced with&#160; the JETPAC tool &#8210; Jet and Tropopause Products for Analysis and Characterization (Manney et&#160; al., 2011).

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Evidence of horizontal and vertical transport of water in the Southern Hemisphere Tropical Tropopause Layer (TTL) from high-resolution balloon observations

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acp-2016-588 ◽

2016 ◽

pp. 1-15

Author(s):

Sergey M. Khaykin ◽

Jean-Pierre Pommereau ◽

Emmanuel D. Riviere ◽

Gerhard Held ◽

Felix Ploeger ◽

...

Keyword(s):

High Resolution ◽

Water Vapour ◽

Southern Hemisphere ◽

Water Budget ◽

Lower Stratosphere ◽

Vertical Profiles ◽

Tropical Tropopause Layer ◽

Horizontal Transport ◽

Tropical Tropopause

High-resolution in situ balloon measurements of water vapour, aerosol, methane and temperature in the upper Tropical Tropopause Layer (TTL) and lower stratosphere are used to evaluate the processes controlling the stratospheric water budget: horizontal transport (inmixing) and hydration by cross-tropopause overshooting updrafts. The obtained in situ evidences of these phenomena are analyzed using satellite observations by Aura MLS (Microwave Limb Sounder) and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) together with trajectory and transport modeling performed using CLaMS (Chemical Lagrangian Model of the Stratosphere) and HYSPLIT (HYbrid Single-Particle Lagrangian Integrated Trajectory) model. Balloon soundings were conducted during March 2012 in Bauru, Brazil (22.3° S) in the frame of the TRO-Pico campaign for studying the impact of convective overshooting on the stratospheric water budget. The balloon payloads included two stratospheric hygrometers: FLASH-B (Fluorescence Lyman-Alpha Stratospheric Hygrometer for Balloon) and Pico-SDLA instrument as well as COBALD (Compact Optical Backscatter Aerosol Detector) sondes, complemented by Vaisala RS-92 radiosondes. Water vapour vertical profiles obtained independently by the two stratospheric hygrometers are in excellent agreement, ensuring credibility of the vertical structures observed. A signature of in-mixing is inferred from a series of vertical profiles, showing coincident enhancements in water vapour and aerosol at the 425 K (18.5 km) level. Trajectory analysis unambiguously links these features to intrusions from the Southern Hemisphere extra-tropical stratosphere, containing more water and aerosol, as demonstrated by MLS and CALIPSO global observations. The in-mixing is successfully reproduced by CLaMS simulations, showing a relatively moist filament extending to 20 S°. A signature of local cross-tropopause transport of water is observed in a particular sounding, performed on a convective day and revealing water vapour enhancements of up to 0.6 ppmv as high as the 404 K (17.8 km) level. These are shown to originate from convective overshoots upwind detected by an S-band weather radar operating locally in Bauru. The accurate in situ observations uncover two independent moisture pathways into the tropical lower stratosphere, whose manifestations are hardly detectable by space-borne sounders. We argue that the moistening by horizontal transport is limited by the weak meridional gradients of water, whereas the fast convective cross-tropopause transport, largely missed by global models, can have a substantial effect, at least at a regional scale.

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Simulation of convective moistening of the extratropical lower stratosphere using a numerical weather prediction model

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-2143-2020 ◽

2020 ◽

Vol 20 (4) ◽

pp. 2143-2159 ◽

Cited By ~ 2

Author(s):

Zhipeng Qu ◽

Yi Huang ◽

Paul A. Vaillancourt ◽

Jason N. S. Cole ◽

Jason A. Milbrandt ◽

...

Keyword(s):

High Resolution ◽

Water Vapour ◽

Lower Stratosphere ◽

Grid Spacing ◽

Water Vapour Content ◽

In Situ Observations ◽

Horizontal Grid ◽

Stratospheric Water Vapour ◽

Resolution Simulation

Abstract. Stratospheric water vapour (SWV) is a climatically important atmospheric constituent due to its impacts on the radiation budget and atmospheric chemical composition. Despite the important role of SWV in the climate system, the processes controlling the distribution and variation in water vapour in the upper troposphere and lower stratosphere (UTLS) are not well understood. In order to better understand the mechanism of transport of water vapour through the tropopause, this study uses the high-resolution Global Environmental Multiscale model of the Environment and Climate Change Canada to simulate a lower stratosphere moistening event over North America. Satellite remote sensing and aircraft in situ observations are used to evaluate the quality of model simulation. The main focus of this study is to evaluate the processes that influence the lower stratosphere water vapour budget, particularly the direct water vapour transport and the moistening due to the ice sublimation. In the high-resolution simulations with horizontal grid spacing of less than 2.5 km, it is found that the main contribution to lower stratospheric moistening is the upward transport caused by the breaking of gravity waves. In contrast, for the lower-resolution simulation with horizontal grid spacing of 10 km, the lower stratospheric moistening is dominated by the sublimation of ice. In comparison with the aircraft in situ observations, the high-resolution simulations predict the water vapour content in the UTLS well, while the lower-resolution simulation overestimates the water vapour content. This overestimation is associated with the overly abundant ice in the UTLS along with a sublimation rate that is too high in the lower stratosphere. The results of this study affirm the strong influence of overshooting convection on the lower stratospheric water vapour and highlight the importance of both dynamics and microphysics in simulating the water vapour distribution in the UTLS region.

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Evaluation of balloon and satellite water vapour measurements in the Southern tropical and subtropical UTLS during the HIBISCUS campaign

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-5299-2009 ◽

2009 ◽

Vol 9 (14) ◽

pp. 5299-5319 ◽

Cited By ~ 14

Author(s):

N. Montoux ◽

A. Hauchecorne ◽

J.-P. Pommereau ◽

F. Lefèvre ◽

G. Durry ◽

...

Keyword(s):

Water Vapour ◽

Lower Stratosphere ◽

Tunable Diode Laser ◽

Absorption Bands ◽

Upper Troposphere ◽

Mixing Ratios ◽

Water Vapour Concentration ◽

Vapour Concentration ◽

Remote Measurements

Abstract. Balloon water vapour in situ and remote measurements in the tropical upper troposphere and lower stratosphere (UTLS) obtained during the HIBISCUS campaign around 20° S in Brazil in February–March 2004 using a tunable diode laser (μSDLA), a surface acoustic wave (SAW) and a Vis-NIR solar occultation spectrometer (SAOZ) on a long duration balloon, have been used for evaluating the performances of satellite borne remote water vapour instruments available at the same latitude and measurement period. In the stratosphere, HALOE displays the best precision (2.5%), followed by SAGE II (7%), MIPAS (10%), SAOZ (20–25%) and SCIAMACHY (35%), all of which show approximately constant H2O mixing ratios between 20–25 km. Compared to HALOE of ±10% accuracy between 0.1–100 hPa, SAGE II and SAOZ show insignificant biases, MIPAS is wetter by 10% and SCIAMACHY dryer by 20%. The currently available GOMOS profiles of 25% precision show a positive vertical gradient in error for identified reasons. Compared to these, the water vapour of the Reprobus Chemistry Transport Model, forced at pressures higher than 95 hPa by the ECMWF analyses, is dryer by about 1 ppmv (20%). In the lower stratosphere between 16–20 km, most notable features are the steep degradation of MIPAS precision below 18 km, and the appearance of biases between instruments far larger than their quoted total uncertainty. HALOE and SAGE II (after spectral adjustment for reducing the bias with HALOE at northern mid-latitudes) both show decreases of water vapour with a minimum at the tropopause not seen by other instruments or the model, possibly attributable to an increasing error in the HALOE altitude registration. Between 16–18 km where the water vapour concentration shows little horizontal variability, and where the μSDLA balloon measurements are not perturbed by outgassing, the average mixing ratios reported by the remote sensing instruments are substantially lower than the 4–5 ppmv observed by the μSDLA. Differences between μSDLA and HALOE and SAGE II (of the order of −2 ppmv), SCIAMACHY, MIPAS and GOMOS (−1 ppmv) and SAOZ (−0.5 ppmv), exceed the 10% uncertainty of μSDLA, implying larger systematic errors than estimated for the various instruments. In the upper troposphere, where the water vapour concentration is highly variable, AIRS v5 appears to be the most consistent within its 25% uncertainty with balloon in-situ measurements as well as ECMWF. Most of the remote measurements show less reliability in the upper troposphere, losing sensitivity possibly because of absorption line saturation in their spectral ranges (HALOE, SAGE II and SCIAMACHY), instrument noise exceeding 100% (MIPAS) or imperfect refraction correction (GOMOS). An exception is the SAOZ-balloon, employing smaller H2O absorption bands in the troposphere.

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SenCity – Evaluating Users’ Experiences of Intelligent Lighting for Well-Being in Smart Cities

Light & Engineering ◽

10.33383/2018-007 ◽

2018 ◽

pp. 60-67

Author(s):

Henrika Pihlajaniemi ◽

Anna Luusua ◽

Eveliina Juntunen

Keyword(s):

Case Studies ◽

Smart City ◽

Smart Cities ◽

Well Being ◽

Evaluation Methods ◽

Data Analyses ◽

Sense Of Security ◽

System Data

This paper presents the evaluation of usersХ experiences in three intelligent lighting pilots in Finland. Two of the case studies are related to the use of intelligent lighting in different kinds of traffic areas, having emphasis on aspects of visibility, traffic and movement safety, and sense of security. The last case study presents a more complex view to the experience of intelligent lighting in smart city contexts. The evaluation methods, tailored to each pilot context, include questionnaires, an urban dashboard, in-situ interviews and observations, evaluation probes, and system data analyses. The applicability of the selected and tested methods is discussed reflecting the process and achieved results.

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Site specific agricultural soil management with the use of new technologies

Global NEST Journal ◽

10.30955/gnj.001203 ◽

2013 ◽

Vol 16 (1) ◽

pp. 59-67

Keyword(s):

New Technologies ◽

Digital Interface ◽

Appropriate Treatment ◽

Wide Range ◽

Soil Variation ◽

Soil Information ◽

Remote Sensing Techniques ◽

Agricultural Areas

The Soil Science Institute of Thessaloniki produces new digitized Soil Maps that provide a useful electronic database for the spatial representation of the soil variation within a region, based on in situ soil sampling, laboratory analyses, GIS techniques and plant nutrition mathematical models, coupled with the local land cadastre. The novelty of these studies is that local agronomists have immediate access to a wide range of soil information by clicking on a field parcel shown in this digital interface and, therefore, can suggest an appropriate treatment (e.g. liming, manure incorporation, desalination, application of proper type and quantity of fertilizer) depending on the field conditions and cultivated crops. A specific case study is presented in the current work with regards to the construction of the digitized Soil Map of the regional unit of Kastoria. The potential of this map can easily be realized by the fact that the mapping of the physicochemical properties of the soils in this region provided delineation zones for differential fertilization management. An experiment was also conducted using remote sensing techniques for the enhancement of the fertilization advisory software database, which is a component of the digitized map, and the optimization of nitrogen management in agricultural areas.

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An Improved Algorithm for Measuring Nitrate Concentrations in Seawater Based on Deep-Ultraviolet Spectrophotometry: A Case Study of the Aoshan Bay Seawater and Western Pacific Seawater

Sensors ◽

10.3390/s21030965 ◽

2021 ◽

Vol 21 (3) ◽

pp. 965

Author(s):

Xingyue Zhu ◽

Kaixiong Yu ◽

Xiaofan Zhu ◽

Juan Su ◽

Chi Wu

Keyword(s):

Weighted Average ◽

Measuring Method ◽

Western Pacific ◽

Nitrate Concentrations ◽

Deep Ultraviolet ◽

Ultraviolet Spectrometer ◽

Seawater Samples ◽

Reflection Probe

Nowadays, it is still a challenge for commercial nitrate sensors to meet the requirement of high accuracy in a complex water. Based on deep-ultraviolet spectral analysis and a regression algorithm, a different measuring method for obtaining the concentration of nitrate in seawater is proposed in this paper. The system consists of a deuterium lamp, an optical fiber splitter module, a reflection probe, temperature and salinity sensors, and a deep-ultraviolet spectrometer. The regression model based on weighted average kernel partial least squares (WA-KPLS) algorithm together with corrections for temperature and salinity (TSC) is established. After that, the seawater samples from Western Pacific and Aoshan Bay in Qingdao, China with the addition of various nitrate concentrations are studied to verify the reliability and accuracy of the method. The results show that the TSC-WA-KPLS algorithm shows the best results when compared against the multiple linear regression (MLR) and ISUS (in situ ultraviolet spectrophotometer) algorithms in the temperatures range of 4–25 °C, with RMSEP of 0.67 µmol/L for Aoshan Bay seawater and 1.08 µmol/L for Western Pacific seawater. The method proposed in this paper is suitable for measuring the nitrate concentration in seawater with higher accuracy, which could find application in the development of in-situ and real-time nitrate sensors.

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Influence of Hydrogeochemistry on Tunnel Drainage in Evaporitic Formations: El Regajal Tunnel Case Study (Aranjuez, Spain)

Sustainability ◽

10.3390/su13031505 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1505

Author(s):

Ignacio Menéndez Pidal ◽

Jose Antonio Mancebo Piqueras ◽

Eugenio Sanz Pérez ◽

Clemente Sáenz Sanz

Keyword(s):

High Speed ◽

Civil Engineering ◽

Saturation Index ◽

The Subject ◽

Under Construction ◽

Underground Flow ◽

Very High ◽

Over Time

Many of the large number of underground works constructed or under construction in recent years are in unfavorable terrains facing unusual situations and construction conditions. This is the case of the subject under study in this paper: a tunnel excavated in evaporitic rocks that experienced significant karstification problems very quickly over time. As a result of this situation, the causes that may underlie this rapid karstification are investigated and a novel methodology is presented in civil engineering where the use of saturation indices for the different mineral specimens present has been crucial. The drainage of the rock massif of El Regajal (Madrid-Toledo, Spain, in the Madrid-Valencia high-speed train line) was studied and permitted the in-situ study of the hydrogeochemical evolution of water flow in the Miocene evaporitic materials of the Tajo Basin as a full-scale testing laboratory, that are conforms as a whole, a single aquifer. The work provides a novel methodology based on the calculation of activities through the hydrogeochemical study of water samples in different piezometers, estimating the saturation index of different saline materials and the dissolution capacity of the brine, which is surprisingly very high despite the high electrical conductivity. The circulating brine appears unsaturated with respect to thenardite, mirabilite, epsomite, glauberite, and halite. The alteration of the underground flow and the consequent renewal of the water of the aquifer by the infiltration water of rain and irrigation is the cause of the hydrogeochemical imbalance and the modification of the characteristics of the massif. These modifications include very important loss of material by dissolution, altering the resistance of the terrain and the increase of the porosity. Simultaneously, different expansive and recrystallization processes that decrease the porosity of the massif were identified in the present work. The hydrogeochemical study allows the evolution of these phenomena to be followed over time, and this, in turn, may facilitate the implementation of preventive works in civil engineering.

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Effects of Infills in the Seismic Performance of an RC Factory Building in Pakistan

Buildings ◽

10.3390/buildings11070276 ◽

2021 ◽

Vol 11 (7) ◽

pp. 276

Author(s):

Nisar Ali Khan ◽

Giorgio Monti ◽

Camillo Nuti ◽

Marco Vailati

Keyword(s):

Numerical Model ◽

Construction Materials ◽

Building Codes ◽

Construction Technique ◽

Infill Walls ◽

Mortar Strength ◽

Materials Used ◽

Seismic Response Of Buildings

Infilled reinforced concrete (IRC) frames are a very common construction typology, not only in developing countries such as Pakistan but also in southern Europe and Western countries, due to their ease of construction and less technical skills required for the construction. Their performance during past earthquakes has been in some cases satisfactory and in other cases inadequate. Significant effort has been made among researchers to improve such performance, but few have highlighted the influence of construction materials used in the infill walls. In some building codes, infills are still considered as non-structural elements, both in the design of new buildings and, sometimes, in the assessment of existing buildings. This is mainly due to some difficulties in modeling their mechanical behavior and also the large variety of typologies, which are difficult to categorize. Some building codes, for example, Eurocode, already address the influence of infill walls in design, but there is still a lack of homogeneity among different codes. For example, the Pakistan building code (PBC) does not address infills, despite being a common construction technique in the country. Past earthquake survey records show that construction materials and infill types significantly affect the seismic response of buildings, thus highlighting the importance of investigating such parameters. This is the object of this work, where a numerical model for infill walls is introduced, which aims at predicting their failure mode, as a function of some essential parameters, such as the friction coefficient between mortar and brick surface and mortar strength, usually disregarded in previous models. A comprehensive case study is presented of a three-story IRC frame located in the city of Mirpur, Pakistan, hit by an earthquake of magnitude 5.9 on 24 September 2019. The results obtained from the numerical model show good agreement with the damage patterns observed in situ, thus highlighting the importance of correctly modeling the infill walls when seismically designing or assessing Pakistani buildings that make use of this technology.

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