COVID-19: Early evening curfews and mobility

Abstract. The midnight temperature maximum (MTM) has been observed in the lower thermosphere by two Fabry–Pérot interferometers (FPIs) at São João do Cariri (7.4° S, 36.5° W) and Cajazeiras (6.9° S, 38.6° W) during 2011, when the solar activity was moderate and the solar flux was between 90 and 155 SFU (1 SFU  =  10−22 W m−2 Hz−1). The MTM is studied in detail using measurements of neutral temperature, wind and airglow relative intensity of OI630.0 nm (referred to as OI6300), and ionospheric parameters, such as virtual height (h′F), the peak height of the F2 region (hmF2), and critical frequency of the F region (foF2), which were measured by a Digisonde instrument (DPS) at Eusébio (3.9° S, 38.4° W; geomagnetic coordinates 7.31° S, 32.40° E for 2011). The MTM peak was observed mostly along the year, except in May, June, and August. The amplitudes of the MTM varied from 64 ± 46 K in April up to 144 ± 48 K in October. The monthly temperature average showed a phase shift in the MTM peak around 0.25 h in September to 2.5 h in December before midnight. On the other hand, in February, March, and April the MTM peak occurred around midnight. International Reference Ionosphere 2012 (IRI-2012) model was compared to the neutral temperature observations and the IRI-2012 model failed in reproducing the MTM peaks. The zonal component of neutral wind flowed eastward the whole night; regardless of the month and the magnitude of the zonal wind, it was typically within the range of 50 to 150 m s−1 during the early evening. The meridional component of the neutral wind changed its direction over the months: from November to February, the meridional wind in the early evening flowed equatorward with a magnitude between 25 and 100 m s−1; in contrast, during the winter months, the meridional wind flowed to the pole within the range of 0 to −50 m s−1. Our results indicate that the reversal (changes in equator to poleward flow) or abatement of the meridional winds is an important factor in the MTM generation. From February to April and from September to December, the h′F and the hmF2 showed an increase around 18:00–20:00 LT within a range between 300 and 550 km and reached a minimal height of about 200–300 km close to midnight; then the layer rose again by about 40 km or, sometimes, remained at constant height. Furthermore, during the winter months, the h′F and hmF2 showed a different behavior; the signature of the pre-reversal enhancement did not appear as in other months and the heights did not exceed 260 and 350 km. Our observation indicated that the midnight collapse of the F region was a consequence of the MTM in the meridional wind that was reflected in the height of the F region. Lastly, the behavior of the OI6300 showed, from February to April and from September to December, an increase in intensity around midnight or 1 h before, which was associated with the MTM, whereas, from May to August, the relative intensity was more intense in the early evening and decayed during the night.

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New results on equatorial thermospheric winds and temperatures from Ethiopia, Africa

Annales Geophysicae ◽

10.5194/angeo-35-333-2017 ◽

2017 ◽

Vol 35 (2) ◽

pp. 333-344 ◽

Cited By ~ 10

Author(s):

Fasil Tesema ◽

Rafael Mesquita ◽

John Meriwether ◽

Baylie Damtie ◽

Melessew Nigussie ◽

...

Keyword(s):

Local Time ◽

Zonal Wind ◽

Meridional Wind ◽

Local Times ◽

Maximum Speed ◽

Wind Speeds ◽

Early Evening ◽

Meridional Winds ◽

Thermospheric Winds ◽

Wind Surge

Abstract. Measurements of equatorial thermospheric winds, temperatures, and 630 nm relative intensities were obtained using an imaging Fabry–Perot interferometer (FPI), which was recently deployed at Bahir Dar University in Ethiopia (11.6° N, 37.4° E, 3.7° N magnetic). The results obtained in this study cover 6 months (53 nights of useable data) between November 2015 and April 2016. The monthly-averaged values, which include local winter and equinox seasons, show the magnitude of the maximum monthly-averaged zonal wind is typically within the range of 70 to 90 ms−1 and is eastward between 19:00 and 21:00 LT. Compared to prior studies of the equatorial thermospheric wind for this local time period, the magnitude is considerably weaker as compared to the maximum zonal wind speed observed in the Peruvian sector but comparable to Brazilian FPI results. During the early evening, the meridional wind speeds are 30 to 50 ms−1 poleward during the winter months and 10 to 25 ms−1 equatorward in the equinox months. The direction of the poleward wind during the winter months is believed to be mainly caused by the existence of the interhemispheric wind flow from the summer to winter hemispheres. An equatorial wind surge is observed later in the evening and is shifted to later local times during the winter months and to earlier local times during the equinox months. Significant night-to-night variations are also observed in the maximum speed of both zonal and meridional winds. The temperature observations show the midnight temperature maximum (MTM) to be generally present between 00:30 and 02:00 LT. The amplitude of the MTM was ∼  110 K in January 2016 with values smaller than this in the other months. The local time difference between the appearance of the MTM and a pre-midnight equatorial wind was generally 60 to 180 min. A meridional wind reversal was also observed after the appearance of the MTM (after 02:00 LT). Climatological models, HWM14 and MSIS-00, were compared to the observations and the HWM14 model generally predicted the zonal wind observations well with the exception of higher model values by 25 ms−1 in the winter months. The HWM14 model meridional wind showed generally good agreement with the observations. Finally, the MSIS-00 model overestimated the temperature by 50 to 75 K during the early evening hours of local winter months. Otherwise, the agreement was generally good, although, in line with prior studies, the model failed to reproduce the MTM peak for any of the 6 months compared with the FPI data.

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Covid-19: Early evening curfews are not effective and may backfire

10.1101/2021.04.13.21255091 ◽

2021 ◽

Author(s):

Sotiris Vandoros ◽

Alina Velias ◽

Sotiris Georganas

Keyword(s):

Natural Experiment ◽

Relative Difference ◽

Relative Increase ◽

Percentage Points ◽

Early Evening ◽

Before And After ◽

Clear Identification ◽

Econometric Approach ◽

The Impact ◽

Indoor Spaces

Background: During the COVID-19 pandemic, some countries have introduced early evening curfews. Several studies try measure the effectiveness of such measures across different countries, but clear identification of effects is elusive. Objective: We examined the impact of an early evening curfew on mobility by studying a shift in curfews from 9pm to 6pm in Greece. Data and Methods: We took advantage of a natural experiment in Greece, where curfews shifted from 9pm to 6pm in one Region, but not in another. We followed a difference-in-difference econometric approach, where we compared trends in mobility in groceries and pharmacies as well as residential spaces before and after the introduction of the 6pm curfew, in the two regions. Results: The relative difference in the time spent in groceries and pharmacies between the two regions before and after the intervention, is statistically insignificant [coeff: -9.95; 95%CI -44.358 to 24.458]. The relative increase in time spent in groceries and pharmacies after the 6pm curfew was only 4.625 percentage points [coeff: 4.625; 95%CI 1.412 to 7.838]. Conclusions: We found that the 6pm instead of 9pm curfew in Athens led to a 4.63 percentage point relative increase in time spent at home and had no effect on time spent in groceries and pharmacies. Considering that this was a result of a 18.75% reduction in hours where people were allowed to leave home, it seems that the early evening curfew led to more crowding in indoor spaces; which may facilitate the spread of disease. Lockdowns and other measures are necessary to tackle Covid-19, but it is important to avoid substitution by activities that contribute further to spreading the virus. Interventions should therefore be based on a thorough analysis of human behaviour.

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Early Evening Questing and Oviposition Activity by the Culex (Diptera: Culicidae) Vectors of West Nile Virus in Northeastern North America

Journal of Medical Entomology ◽

10.1093/jmedent/44.2.211 ◽

2007 ◽

Vol 44 (2) ◽

pp. 211-214 ◽

Cited By ~ 9

Author(s):

Michael R. Reddy ◽

Timothy J. Lepore ◽

Richard J. Pollack ◽

Anthony E. Kiszewski ◽

Andrew Spielman ◽

...

Keyword(s):

West Nile Virus ◽

North America ◽

West Nile ◽

Northeastern North America ◽

Early Evening

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Diurnal and Seasonal Lightning Variability over the Gulf Stream and the Gulf of Mexico

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-14-0233.1 ◽

2015 ◽

Vol 72 (7) ◽

pp. 2657-2665 ◽

Cited By ~ 17

Author(s):

Katrina S. Virts ◽

John M. Wallace ◽

Michael L. Hutchins ◽

Robert H. Holzworth

Keyword(s):

Gulf Of Mexico ◽

Diurnal Cycle ◽

Gulf Stream ◽

Land Surface ◽

Southeastern United States ◽

Surface Wind ◽

Tropical Rainfall Measuring Mission ◽

Sea Breeze ◽

Near Surface ◽

Early Evening

Recent observations from the World Wide Lightning Location Network (WWLLN) reveal a pronounced lightning maximum over the warm waters of the Gulf Stream that exhibits distinct diurnal and seasonal variability. Lightning is most frequent during summer (June–August). During afternoon and early evening, lightning is enhanced just onshore of the coast of the southeastern United States because of daytime heating of the land surface and the resulting sea-breeze circulations and convection. Near-surface wind observations from the Quick Scatterometer (QuikSCAT) satellite indicate divergence over the Gulf of Mexico and portions of the Gulf Stream at 1800 LT, at which time lightning activity is suppressed there. Lightning frequency exhibits a broad maximum over the Gulf Stream from evening through noon of the following day, and QuikSCAT wind observations at 0600 LT indicate low-level winds blowing away from the continent and converging over the Gulf Stream. Over the northern Gulf of Mexico, lightning is most frequent from around sunrise through late morning. During winter, lightning exhibits a weak diurnal cycle over the Gulf Stream, with most frequent lightning during the evening. Precipitation rates from a 3-hourly gridded dataset that incorporates observations from Tropical Rainfall Measuring Mission (TRMM), as well as other satellites, exhibit a diurnal cycle over the Gulf Stream that lags the lightning diurnal cycle by several hours.

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The early evening boundary layer transition

Quarterly Journal of the Royal Meteorological Society ◽

10.1002/qj.49710745205 ◽

2007 ◽

Vol 107 (452) ◽

pp. 329-343 ◽

Cited By ~ 51

Author(s):

L. Mahrt

Keyword(s):

Boundary Layer ◽

Boundary Layer Transition ◽

Layer Transition ◽

Early Evening

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A Geothermal-Solar Hybrid Power Plant with Thermal Energy Storage

Energies ◽

10.3390/en13051018 ◽

2020 ◽

Vol 13 (5) ◽

pp. 1018 ◽

Cited By ~ 1

Author(s):

Brady Bokelman ◽

Efstathios E. Michaelides ◽

Dimitrios N. Michaelides

Keyword(s):

Power Plant ◽

Peak Power ◽

Solar Power ◽

Organic Rankine Cycle ◽

Rankine Cycle ◽

Solar Power Plant ◽

Electricity Grid ◽

Early Evening ◽

Binary Geothermal Power Plant ◽

Continuous Power

The concept of a geothermal-solar power plant is proposed that provides dispatchable power to the local electricity grid. The power plant generates significantly more power in the late afternoon and early evening hours of the summer, when air-conditioning use is high and peak power is demanded. The unit operates in two modes: a) as a binary geothermal power plant utilizing a subcritical Organic Rankine Cycle; and b) as a hybrid geothermal-solar power plant utilizing a supercritical cycle with solar-supplied superheat. Thermal storage allows for continuous power generation in the early evening hours. The switch to the second mode and the addition of solar energy into the cycle increases the electric power generated by a large factor—2 to 9 times—during peak power demand at a higher efficiency (16.8%). The constant supply of geothermal brine and heat storage in molten salts enables this power plant to produce dispatchable power in its two modes of operation with an exergetic efficiency higher than 30%.

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Boredom effects on sleepiness/alertness in the early afternoon vs. early evening and interactions with warm ambient temperature

British Journal of Psychology ◽

10.1111/j.2044-8295.1994.tb02527.x ◽

1994 ◽

Vol 85 (3) ◽

pp. 317-333 ◽

Cited By ~ 25

Author(s):

V. Mavjee ◽

J. A. Home

Keyword(s):

Ambient Temperature ◽

Early Evening ◽

Early Afternoon

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Possible Triggering Mechanisms for Severe Storms in SESAME-AVE IV (9–10 May 1979)

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-63.5.503 ◽

1982 ◽

Vol 63 (5) ◽

pp. 503-516 ◽

Cited By ~ 21

Author(s):

Yoshi Ogura ◽

Hann-Ming Juang ◽

Ke-Su Zhang ◽

Su-Tzai Soong

Keyword(s):

Boundary Layer ◽

Vertical Wind Shear ◽

Sea Breeze ◽

Storm Event ◽

Severe Storms ◽

Stationary Front ◽

Early Evening ◽

Strong Inversion ◽

Triggering Mechanisms ◽

Reported Data

The SESAME-AVE IV (9–10 May 1979) rawinsonde data were analyzed to uncover possible triggering mechanisms for severe storms that developed over western Oklahoma and Texas. The high frequency of observations (at 3 h intervals) and high vertical resolution of reported data (at 25 mb intervals) at all stations permitted investigation of the diurnal variation of the planetary boundary layer on the synoptic scale. Thunderstorms developed first just ahead of a stationary front over the Texas panhandle on the afternoon of 9 May. This area was characterized by the absence of a strong inversion (or “lid”) that represented an interface between very warm and dry air aloft, and warm moist tropical air below. Apparently, mesoscale low-level ascending motion associated with frontal lifting and/or the inland sea breeze effect led to the removal of the lid. Another noteworthy feature in this storm event was the strong vertical wind shear at low and middle levels over the storm area. When combined with the development of a deep boundary layer with weak stratification during the daytime, the Richardson number became less than one in the boundary layer in the prestorm situation. The results of our numerical linear stability analysis indicate that the observed basic states were indeed symmetrically unstable. This may suggest that the triggering processes were argumented by symmetric instability. Although a well defined dry line was present, it does not seem to have contributed directly to initiation of storms in this case. It also was observed that, as the thermal low began to weaken in the early evening, the cold air behind a stationary front started advancing eastward and helped to extend the line of thunderstorms deep into central Texas. This may be another process whereby some storms prefer to develop in the late afternoon or early evening.

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