Sensitivity of tropical monsoon precipitation to the latitude of stratospheric aerosol injections

PurposeThis study aims to investigate the heat transfer mechanism of the uniforms used by people working in hot, humid and windy environments. Furthermore, the effectiveness of an opening structure added to the armpit of the uniforms in improving thermal comfort was comparatively examined.Design/methodology/approachA set of uniforms was tested with the opening at the armpit alternatively zipped or unzipped. Thermal manikin and human tests were performed in a climatic chamber simulating the specific environmental conditions, including wind speeds at four levels (0.15, 0.5, 2, 4 m/s) and relative humidities at two levels (50 and 85%). Static and dynamic thermal insulations of clothing (IT) were examined by the thermal manikin tests. The human bodies' thermal responses, including heart rates (HR), eardrum temperatures (Te), skin temperatures (Tsk) and subjective perceptions, were given by the human tests.FindingsSpecial mechanisms of heat transfer in the specific uniforms used in tropical monsoon climates were revealed. Reductions on IT were caused by the movement of the human body and the environmental wind, and the empirical equations would underestimate this reduction. The opening at the armpit was able to prompt more heat transfer under dynamic condition, with reducing the IT by 11.8%, lowering the mean Tsk by 0.92°C, and significantly improving the subjective perceptions (p < 0.05). The heat exhaustion was alleviated with lowering the Te by 0.32°C.Originality/valueThis study managed to improve the thermal performance of uniforms for workers under unforgiving conditions. The evaluation and design methods introduced by this study provided practical guidance for similar products with strict dress codes and cost control requirements based on the findings from thorough product tests and analysis.

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Spatio-temporal variability of the salinity intrusion, mixing, and estuarine turbidity maximum in a tide-dominated tropical monsoon estuary

Continental Shelf Research ◽

10.1016/j.csr.2021.104477 ◽

2021 ◽

pp. 104477

Author(s):

Gubash Azhikodan ◽

Nay Oo Hlaing ◽

Katsuhide Yokoyama ◽

Masashi Kodama

Keyword(s):

Temporal Variability ◽

Turbidity Maximum ◽

Estuarine Turbidity Maximum ◽

Salinity Intrusion ◽

Tropical Monsoon ◽

Spatio Temporal

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Updated and outdated reservations about research into stratospheric aerosol injection

Climatic Change ◽

10.1007/s10584-021-03017-z ◽

2021 ◽

Vol 164 (3-4) ◽

Author(s):

Wake Smith ◽

Claire Henly

Keyword(s):

Recent Literature ◽

Early Stage ◽

Stratospheric Aerosol ◽

Research Community ◽

Slippery Slope ◽

Lock In ◽

Stratospheric Aerosol Injection

AbstractIn this paper, we seek to ground discussions of the governance of stratospheric aerosol injection research in recent literature about the field including an updated understanding of the technology’s deployment logistics and scale, pattern of effects, and research pathways. Relying upon this literature, we evaluate several common reservations regarding the governance of pre-deployment research and testing including covert deployment, technological lock-in, weaponization, slippery slope, and the blurry line between research and deployment. We conclude that these reservations are no longer supported by literature. However, we do not argue that there is no reason for concern. Instead, we enumerate alternative bases for caution about research into stratospheric aerosol injection which are supported by an up-to-date understanding of the literature. We conclude that in order to establish the correct degree and type of governance for stratospheric aerosol injection research, the research community must focus its attention on these well-grounded reservations. However, while these reservations are supported and warrant further attention, we conclude that none currently justifies restrictive governance of early-stage stratospheric aerosol injection research.

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Differences in the Evolution of Pyrocumulonimbus and Volcanic Stratospheric Plumes as Observed by CATS and CALIOP Space-Based Lidars

Atmosphere ◽

10.3390/atmos11101035 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1035

Author(s):

Kenneth Christian ◽

John Yorks ◽

Sampa Das

Keyword(s):

Pacific Northwest ◽

Stratospheric Aerosol ◽

Volcanic Aerosol ◽

Volcanic Plumes ◽

Size And Shape ◽

Altitude Dependence ◽

Volcanic Events ◽

Spatial Propagation ◽

Depolarization Ratios

Recent fire seasons have featured volcanic-sized injections of smoke aerosols into the stratosphere where they persist for many months. Unfortunately, the aging and transport of these aerosols are not well understood. Using space-based lidar, the vertical and spatial propagation of these aerosols can be tracked and inferences can be made as to their size and shape. In this study, space-based CATS and CALIOP lidar were used to track the evolution of the stratospheric aerosol plumes resulting from the 2019–2020 Australian bushfire and 2017 Pacific Northwest pyrocumulonimbus events and were compared to two volcanic events: Calbuco (2015) and Puyehue (2011). The pyrocumulonimbus and volcanic aerosol plumes evolved distinctly, with pyrocumulonimbus plumes rising upwards of 10 km after injection to altitudes of 30 km or more, compared to small to modest altitude increases in the volcanic plumes. We also show that layer-integrated depolarization ratios in these large pyrocumulonimbus plumes have a strong altitude dependence with more irregularly shaped particles in the higher altitude plumes, unlike the volcanic events studied.

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Improved tropospheric and stratospheric sulfur cycle in the aerosol–chemistry–climate model SOCOL-AERv2

Geoscientific Model Development ◽

10.5194/gmd-12-3863-2019 ◽

2019 ◽

Vol 12 (9) ◽

pp. 3863-3887 ◽

Cited By ~ 2

Author(s):

Aryeh Feinberg ◽

Timofei Sukhodolov ◽

Bei-Ping Luo ◽

Eugene Rozanov ◽

Lenny H. E. Winkel ◽

...

Keyword(s):

Climate Model ◽

Model Performance ◽

Stratospheric Aerosol ◽

Sulfur Cycle ◽

Sulfate Aerosol ◽

Tropospheric Chemistry ◽

Sulfur Deposition ◽

Aerosol Chemistry ◽

Deposition Fluxes ◽

Aerosol Model

Abstract. SOCOL-AERv1 was developed as an aerosol–chemistry–climate model to study the stratospheric sulfur cycle and its influence on climate and the ozone layer. It includes a sectional aerosol model that tracks the sulfate particle size distribution in 40 size bins, between 0.39 nm and 3.2 µm. Sheng et al. (2015) showed that SOCOL-AERv1 successfully matched observable quantities related to stratospheric aerosol. In the meantime, SOCOL-AER has undergone significant improvements and more observational datasets have become available. In producing SOCOL-AERv2 we have implemented several updates to the model: adding interactive deposition schemes, improving the sulfate mass and particle number conservation, and expanding the tropospheric chemistry scheme. We compare the two versions of the model with background stratospheric sulfate aerosol observations, stratospheric aerosol evolution after Pinatubo, and ground-based sulfur deposition networks. SOCOL-AERv2 shows similar levels of agreement as SOCOL-AERv1 with satellite-measured extinctions and in situ optical particle counter (OPC) balloon flights. The volcanically quiescent total stratospheric aerosol burden simulated in SOCOL-AERv2 has increased from 109 Gg of sulfur (S) to 160 Gg S, matching the newly available satellite estimate of 165 Gg S. However, SOCOL-AERv2 simulates too high cross-tropopause transport of tropospheric SO2 and/or sulfate aerosol, leading to an overestimation of lower stratospheric aerosol. Due to the current lack of upper tropospheric SO2 measurements and the neglect of organic aerosol in the model, the lower stratospheric bias of SOCOL-AERv2 was not further improved. Model performance under volcanically perturbed conditions has also undergone some changes, resulting in a slightly shorter volcanic aerosol lifetime after the Pinatubo eruption. With the improved deposition schemes of SOCOL-AERv2, simulated sulfur wet deposition fluxes are within a factor of 2 of measured deposition fluxes at 78 % of the measurement stations globally, an agreement which is on par with previous model intercomparison studies. Because of these improvements, SOCOL-AERv2 will be better suited to studying changes in atmospheric sulfur deposition due to variations in climate and emissions.

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Tropical monsoon forests of Vietnam (Results of 20 Years of Phytoecological Research)

Biology Bulletin ◽

10.1134/s1062359013020076 ◽

2013 ◽

Vol 40 (2) ◽

pp. 187-196 ◽

Cited By ~ 3

Author(s):

A. N. Kuznetsov ◽

S. P. Kuznetsova

Keyword(s):

Tropical Monsoon ◽

Monsoon Forests

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