Five-day planetary waves as seen by the Odin satellite and the ground-based Kiruna millimeter wave radiometer in January–March 2005

2008 ◽  
Vol 86 (3) ◽  
pp. 459-466 ◽  
Author(s):  
Alla Belova ◽  
Sheila Kirkwood ◽  
U Raffalski ◽  
Gerhard Kopp ◽  
Gerd Hochschild ◽  
...  
Keyword(s):  
Millimeter Wave ◽  
Planetary Wave ◽  
Temperature Data ◽  
Planetary Waves ◽  
Comparison Interval ◽  
Millimeter Wave Radiometer ◽  
Winter Hemisphere ◽  
Wave Properties ◽  
Ozone Levels

The signature of five-day planetary waves in ozone and temperature data from the advanced sub-millimeter radiometer aboard the Odin satellite is examined. The period January–March 2005 and heights from 24–56 km are used. We find highest wave amplitudes in both temperature and ozone in the winter hemisphere at 60°N-70°N. The relative phases between ozone and temperature perturbations show the expected antiphase behaviour in the photochemistry-dominated region at about 40 km altitude. We compare the global planetary wave properties from Odin with five-day perturbations in ozone measured by the millimeter wave radiometer in Kiruna (KIMRA, 67°N, 20°E). In the early part of the comparison interval (January–February) at 40 km, we find good correlation between the two in terms of both phase and amplitude of the perturbations. In the latter part of the comparison interval (March) where mean ozone levels are higher, the amplitudes of the ozone five-day perturbations over Kiruna are much higher than the wave amplitudes found using Odin. We conclude that five-day variations in ozone due to planetary waves can be detected by KIMRA in some circumstances, but that other sources of variability dominate at other heights and times. PACS No.: 94.10.Jd

First hints for the influence of planetary waves on extreme temperature events with a focus on Bavaria and the Alpine Region

2020 ◽  
Author(s):  
Dominik Laux ◽  
Lisa Küchelbacher ◽  
Sabine Wüst ◽  
Michael Bittner
Keyword(s):  
Planetary Wave ◽  
Extreme Temperature ◽  
Wave Activity ◽  
Temperature Data ◽  
Alpine Region ◽  
Planetary Waves ◽  
Occurrence Frequency ◽  
Extreme Temperature Events ◽  
Cold Events ◽  
Heat Events

<p>Planetary waves are global scale waves in the atmosphere, which mainly dominate the atmospheric circulation in mid latitudes. It is discussed whether planetary wave activity increases due to the decrease of the meridional temperature gradient between the equator and the pole. As a result, large-scale weather patterns in mid latitudes should change, leading to a change in the occurrence of extreme weather events.</p><p>In order to analyze whether the occurrence of extreme temperature events has already changed, an algorithm was developed that identifies extreme temperature events in ERA5 temperature data from 1979 to 2019 in different height levels (1000hPa – 1hPa). We analyze the occurrence frequency of extreme temperature events in mid latitudes of the Northern Hemisphere as well as in Bavaria and in the Alpine region. To relate changes in the occurrence of extreme temperature events to possible changes of the planetary wave activity, we use the so-called dynamic activity index (DAI), which is operationally derived from ERA reanalysis temperature data at DLR.</p><p>In the troposphere, our analyses show that the occurrence frequency of heat events increases whereas the opposite holds for cold events. This is consistent with the expected effect of increasing average temperatures on the occurrence frequency of extreme temperature events. In the stratosphere, however, we observe an increase of cold events and a constant number of heat events. We conclude that tropospheric and stratospheric driving factors for the occurrence of extreme temperature events differ. The stratospheric development can be explained by increasing planetary wave activity as it is deduced from the DAI.</p><p>This work received funding from the Bavarian State Ministry of the Environment and Consumer Protection.</p>

Millimeter wave radiometer installation in Río Gallegos, southern Argentina

2011 ◽  
Author(s):  
P. F. Orte ◽  
J. Salvador ◽  
E. Wolfram ◽  
R. D'Elia ◽  
T. Nagahama ◽  
...  
Keyword(s):  
Millimeter Wave ◽  
Millimeter Wave Radiometer

Millimeter-Wave Properties and Structure of Gradient Co–Ir Films Deposited on Opal Matrix

2014 ◽  
Vol 13 (1) ◽  
pp. 3-9 ◽  
Author(s):  
Anatoly B. Rinkevich ◽  
Mikhail I. Samoilovich ◽  
Svetlana M. Klescheva ◽  
Dmitry V. Perov ◽  
Albert M. Burkhanov ◽  
...  
Keyword(s):  
Millimeter Wave ◽  
Opal Matrix ◽  
Wave Properties

scholarly journals COMPARISON OF WAVE ACTIVITY IN THE MESOPAUSE REGION AT MAIMAGA STATION WITH EOS MLS (AURA) TEMPERATURE DATA AND ACTIVITY OF PLANETARY WAVES AT TIKSI STATION

2019 ◽  
pp. 182-189
Author(s):  
В.И. Сивцева ◽  
П.П. Аммосов ◽  
Г.А. Гаврильева ◽  
И.И. Колтовской ◽  
А.М. Аммосова
Keyword(s):  
Gravity Waves ◽  
Internal Gravity Waves ◽  
Temperature Data ◽  
Planetary Waves ◽  
Winter Period ◽  
Temperature Profiles ◽  
Night Temperature ◽  
Mesopause Region ◽  
The Difference ◽  
The Waves

Исследованы данные температуры области мезопаузы, полученные за период 2013-2018 гг. на станции Маймага (63.04N, 129.51E) и за период 2015-2018 гг. на станции Тикси (71.58 N, 128.77 E). В зимний период сезона наблюдений 2014-2015 характеристика активности внутренних гравитационных волн (ВГВ) gwимеет более низкие значения, чем в другие сезоны, а средненочная температура, наоборот, превышает аналогичные значения в другие сезоны. Для сопоставления рассматривались спутниковые данные температурных профилей полученные EOS MLS (Aura). После выделения и вычитания вклада гравитационной составляющей из температурных профилей EOS MLS для области над станцией Маймага заметно отличие в зимней стратопаузе сезона 2014-2015. В этот сезон в зимний период, с учетом вычета вклада флуктуаций температуры обусловленных ВГВ, наблюдается отсутствие резких потеплений в районе стратопаузы в отличие от остальных сезонов. Измерение параметров планетарных волн в течение периода 2015-2018 гг. совместных наблюдений на станциях Маймага и Тикси показали, что фазы наблюдаемых на обеих станциях волн совпадают, а амплитуды на станции Тикси несколько (12 К) превышают амплитуды на станции Маймага. The temperature data of the mesopause region obtained for the period 2013-2018 at the station Maimaga (63.04 N, 129.51 E) and for the period 2015-2018 at the station Tiksi (71.58 N, 128.77 E) was investigated. During the winter period of the 20142015 observation season, the characteristic of the internal gravity waves (IGW) activity sgw has lower values than in other seasons, and the average night temperature of the mesopause region, on the contrary, exceeds corresponding values in other seasons. For comparison, satellite data of temperature profiles obtained by EOS MLS (Aura) are given. After isolating and subtracting the contribution of the gravitaty waves from the EOS MLS temperature profiles for the region above the st. Maimaga, the difference in the winter stratopause of the 2014-2015 season is noticeable. In this season in winter there is a lack of sharp warming in the stratopause region, in contrast to other seasons, taking into account the deduction of the contribution of temperature fluctuations due to IGW. Measurement of the parameters of planetary waves during the period 2015-2018 of joint observations at Maimaga and Tiksi stations showed that the phases of the waves observed at both stations coincide, and the amplitudes at Tiksi station are several (1-2 K) higher than the amplitudes at Maimaga station.

scholarly journals Five-day planetary waves in the middle atmosphere from Odin satellite data and ground-based instruments in Northern Hemisphere summer 2003, 2004, 2005 and 2007

2008 ◽  
Vol 26 (11) ◽  
pp. 3557-3570 ◽  
Author(s):  
A. Belova ◽  
S. Kirkwood ◽  
D. Murtagh ◽  
N. Mitchell ◽  
W. Singer ◽  
...  
Keyword(s):  
Wave Propagation ◽  
Northern Hemisphere ◽  
Middle Atmosphere ◽  
Numerical Models ◽  
Baroclinic Instability ◽  
Temperature Fluctuations ◽  
Planetary Waves ◽  
Summer Hemisphere ◽  
Winter Hemisphere

Abstract. A number of studies have shown that 5-day planetary waves modulate noctilucent clouds and the closely related Polar Mesosphere Summer Echoes (PMSE) at the summer mesopause. Summer stratospheric winds should inhibit wave propagation through the stratosphere and, although some numerical models (Geisler and Dickinson, 1976) do show a possibility for upward wave propagation, it has also been suggested that the upward propagation may in practice be confined to the winter hemisphere with horizontal propagation of the wave from the winter to the summer hemisphere at mesosphere heights causing the effects observed at the summer mesopause. It has further been proposed (Garcia et al., 2005) that 5-day planetary waves observed in the summer mesosphere could be excited in-situ by baroclinic instability in the upper mesosphere. In this study, we first extract and analyze 5-day planetary wave characteristics on a global scale in the middle atmosphere (up to 54 km in temperature, and up to 68 km in ozone concentration) using measurements by the Odin satellite for selected days during northern hemisphere summer from 2003, 2004, 2005 and 2007. Second, we show that 5-day temperature fluctuations consistent with westward-traveling 5-day waves are present at the summer mesopause, using local ground-based meteor-radar observations. Finally we examine whether any of three possible sources of the detected temperature fluctuations at the summer mesopause can be excluded: upward propagation from the stratosphere in the summer-hemisphere, horizontal propagation from the winter-hemisphere or in-situ excitation as a result of the baroclinic instability. We find that in one case, far from solstice, the baroclinic instability is unlikely to be involved. In one further case, close to solstice, upward propagation in the same hemisphere seems to be ruled out. In all other cases, all or any of the three proposed mechanisms are consistent with the observations.

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