Spatio-temporal variability of the atmospheric boundary layer depth over the Paris agglomeration: An assessment of the impact of the urban heat island intensity

Pal, Sandip; Xueref-Rémy, Irène; Ammoura, L.; Chazette, Patrick; Gibert, Fabien; Royer, P.; Dieudonné, Elsa; Dupont, J.-C.; Haeffelin, Martial; Lac, Christine; Lopez, Morgan; Morille, Yohann; Ravetta, François

doi:10.1016/j.atmosenv.2012.09.046

Cited by 129 publications

(118 citation statements)

References 31 publications

Supporting

Mentioning

106

Contrasting

Unclassified

Order By: Relevance

“…This efficiency helps obtain significantly improved near-range performance for monitoring shallow NBL. Thus, ceilometers are found to be important candidates, in particular for monitoring the transition from stable boundary layer (SBL) to CBL, or from shallow CBL to a growing CBL regime [50]. On the other hand, due to the high power laser transmitter used in the LiDAR systems, they are suitable for monitoring daytime CBL height with sufficient accuracy as was demonstrated by many researchers in the past.…”

Section: Ceilometer and Lidar Measurementsmentioning

confidence: 99%

“…Additionally, while comparing performance of LiDAR and ceilometer, Tsaknakis et al [72] found that during the daytime the CL31 ceilometer was able to correctly detect the presence of various aerosol layers only after averaging the signals for sufficiently longer term period (3 h). An averaging time of more than few tens of minutes is not suitable for determining CBL depths, in particular during the morning transition period, when CBL depth often increases with a growth rate of more than 300 m/h (e.g., [45,50]). …”

Section: Ceilometer and Lidar Measurementsmentioning

confidence: 99%

“…On the other hand, in many LiDAR systems with large telescopes (more than 50-cm diameter) full overlap (i.e., O(R) of 1) is achieved at a distance of more than 1 km (e.g., [47,48]). For LiDAR systems with a smaller telescope (between 20 and 40 cm diameter), the complete overlap is found to be between 150 and 600 m above ground (e.g., [46][47][48][49][50]). Significant errors exist in the profile of the LiDAR signal received from the region of incomplete overlap, i.e., close to the ground where the aerosol particles are both most abundant and most variable [49].…”

Section: Theoretical and Experimental Approaches To Correct Lidar Sigmentioning

confidence: 99%

“…Ceilometers are mostly dedicated to cloud base height/cloud layer measurements and vertical visibility for meteorological and aviation applications. However, due to recent progresses in low-cost laser systems, ceilometers have been found useful for detecting aerosols in general and especially for detecting volcanic ash layers, and recently for determining z i (e.g., [50]). Many researchers in the past discussed in detail the potential differences between the efficiency of LiDAR and ceilometer systems for monitoring ABL (e.g., [24]).…”

Section: Ceilometer and Lidar Measurementsmentioning

confidence: 99%

See 3 more Smart Citations

Monitoring Depth of Shallow Atmospheric Boundary Layer to Complement LiDAR Measurements Affected by Partial Overlap

Pal

2014

Remote Sensing

View full text Add to dashboard Cite

Abstract:There is compelling evidence that the incomplete laser beam receiver field-of-view overlap (i.e., partial overlap) of ground-based vertically-pointing aerosol LiDAR restricts the observational range for detecting aerosol layer boundaries to a certain height above the LiDAR. This height varies from one to few hundreds of meters, depending on the transceiver geometry. The range, or height of full overlap, is defined as the minimum distance at which the laser beam is completely imaged onto the detector through the field stop in the receiver optics. Thus, the LiDAR signal below the height of full overlap remains erroneous. In effect, it is not possible to derive the atmospheric boundary layer (ABL) top (z i ) below the height of full overlap using lidar measurements alone. This problem makes determination of the nocturnal z i almost impossible, as the nocturnal z i is often lower than the minimum possible retrieved height due to incomplete overlap of lidar. Detailed studies of the nocturnal boundary layer or of variability of low z i would require changes in the LiDAR configuration such that a complete transceiver overlap could be achieved at a much lower height. Otherwise, improvements in the system configuration or deployment (e.g., scanning LiDAR) are needed. However, these improvements are challenging due to the instrument configuration and the need for Raman channel signal, eye-safe laser transmitter for scanning deployment, etc. This paper presents a brief review of some of the challenges and opportunities in overcoming the partial overlap of the LiDAR transceiver to determine z i below the height of full-overlap using complementary approaches to derive low z i . A comprehensive discussion focusing on four different techniques is presented. These are based on the combined (1) ceilometer and LiDAR; (2) tower-based trace gas (e.g., CO 2 ) concentration profiles and LiDAR measurements; (3) 222 Rn budget approach and LiDAR-derived results; and (4) encroachment model and LiDAR observations.

show abstract

Section: Ceilometer and Lidar Measurementsmentioning

confidence: 99%

Section: Ceilometer and Lidar Measurementsmentioning

confidence: 99%

Section: Theoretical and Experimental Approaches To Correct Lidar Sigmentioning

confidence: 99%

Section: Ceilometer and Lidar Measurementsmentioning

confidence: 99%

See 2 more Smart Citations

Monitoring Depth of Shallow Atmospheric Boundary Layer to Complement LiDAR Measurements Affected by Partial Overlap

Pal

2014

Remote Sensing

View full text Add to dashboard Cite

show abstract

“…However, previous studies demonstrate that the global carbon cycle cannot be predicted exactly by existing atmospheric models [5][6][7]. The natural geographic distribution and temporal variability of CO 2 sources and sinks remain largely uncertain, especially for urbanized areas where high-level sources are located [8,9]. In this case, precise monitoring of atmospheric CO 2 concentration is necessary.…”

Section: Introductionmentioning

confidence: 99%

Feasibility Study of Multi-Wavelength Differential Absorption LIDAR for CO2 Monitoring

Xiang

Liang

et al. 2016

Atmosphere

View full text Add to dashboard Cite

Abstract:To obtain a better understanding of carbon cycle and accurate climate prediction models, highly accurate and temporal resolution observation of atmospheric CO 2 is necessary. Differential absorption LIDAR (DIAL) remote sensing is a promising technology to detect atmospheric CO 2 . However, the traditional DIAL system is the dual-wavelength DIAL (DW-DIAL), which has strict requirements for wavelength accuracy and stability. Moreover, for on-line and off-line wavelengths, the system's optical efficiency and the change of atmospheric parameters are assumed to be the same in the DW-DIAL system. This assumption inevitably produces measurement errors, especially under rapid aerosol changes. In this study, a multi-wavelength DIAL (MW-DIAL) is proposed to map atmospheric CO 2 concentration. The MW-DIAL conducts inversion with one on-line and multiple off-line wavelengths. Multiple concentrations of CO 2 are then obtained through difference processing between the single on-line and each of the off-line wavelengths. In addition, the least square method is adopted to optimize inversion results. Consequently, the inversion concentration of CO 2 in the MW-DIAL system is found to be the weighted average of the multiple concentrations. Simulation analysis and laboratory experiments were conducted to evaluate the inversion precision of MW-DIAL. For comparison, traditional DW-DIAL simulations were also conducted. Simulation analysis demonstrated that, given the drifting wavelengths of the laser, the detection accuracy of CO 2 when using MW-DIAL is higher than that when using DW-DIAL, especially when the drift is large. A laboratory experiment was also performed to verify the simulation analysis.

show abstract

Investigation of the atmospheric boundary layer depth variability and its impact on the ²²²Rn concentration at a rural site in France

et al. 2015

Self Cite

View full text Add to dashboard Cite

Continuous monitoring of the atmospheric boundary layer (ABL) depth (z i ) is important for investigations of trace gases with near-surface sources. The aim of this study is to examine the temporal variability of z i on both diurnal and seasonal time scales over a full year (2011) and relate these changes to the atmospheric 222 Rn concentrations (C Rn ) measured near the top of a 200 m tower at a rural site (Trainou) in France. Continuous z i estimates were made using a combination of lidar and hourly four-height carbon dioxide (CO 2 ) profile measurements. Over the diurnal cycle, the 180 m C Rn reached a maximum in the late morning as the growing ABL passed through the inlet height (180 m) transporting upward high C Rn air from the nocturnal boundary layer. During late afternoon, a minimum in the C Rn occurred mainly due to ABL-mixing. We argue that ABL dilution occurs in two stages: first, during the rapid morning growth into the residual layer, and second, during afternoon with the free atmosphere when z i has reached its quasi-stationary height (around 750 m in winter or 1700 m in summer). An anticorrelation (R 2 of À0.49) was found while performing a linear regression analysis between the daily z i growth rates and the corresponding changes in the C Rn illustrating the ABL-dilution effect. We also analyzed the numerical proportions of the time within a season when z i remained lower than the inlet height and found a clear seasonal variability for the nighttime measurements with higher number of cases with shallow z i (<200 m) in winter (67.3%) than in summer (33.9%) and spring (54.5%). Thus, this pilot study helps delineate the impact of z i on C Rn at the site mainly for different regimes of ABL, in particular, during the times when the z i is above the measurement height. It is suggested that when the z i is well below the inlet height, measurements are most possibly indicative of the residual layer 222 Rn, an important issue that should be considered in the mass budget approach.

show abstract

Spatio-temporal variability of the atmospheric boundary layer depth over the Paris agglomeration: An assessment of the impact of the urban heat island intensity

Cited by 129 publications

References 31 publications

Monitoring Depth of Shallow Atmospheric Boundary Layer to Complement LiDAR Measurements Affected by Partial Overlap

Monitoring Depth of Shallow Atmospheric Boundary Layer to Complement LiDAR Measurements Affected by Partial Overlap

Feasibility Study of Multi-Wavelength Differential Absorption LIDAR for CO2 Monitoring

Investigation of the atmospheric boundary layer depth variability and its impact on the ²²²Rn concentration at a rural site in France

Contact Info

Product

Resources

About

Spatio-temporal variability of the atmospheric boundary layer depth over the Paris agglomeration: An assessment of the impact of the urban heat island intensity

Cited by 129 publications

References 31 publications

Monitoring Depth of Shallow Atmospheric Boundary Layer to Complement LiDAR Measurements Affected by Partial Overlap

Monitoring Depth of Shallow Atmospheric Boundary Layer to Complement LiDAR Measurements Affected by Partial Overlap

Feasibility Study of Multi-Wavelength Differential Absorption LIDAR for CO2 Monitoring

Investigation of the atmospheric boundary layer depth variability and its impact on the 222Rn concentration at a rural site in France

Contact Info

Product

Resources

About

Investigation of the atmospheric boundary layer depth variability and its impact on the ²²²Rn concentration at a rural site in France