1) The document discusses observations of mesospheric gravity waves over the Andes Mountains from both ground-based and satellite instruments.
2) Ground-based observations have been made at the Andes Lidar Observatory in Cerro Pachon, Chile since 2009, measuring gravity wave activity in the mesosphere through OH layer measurements.
3) Complementary satellite observations have been made by the SABER instrument on the TIMED satellite, which has measured increased temperature variance in the mesosphere over the Andes during winter months that indicates stronger gravity wave activity.
Meridional brightness temperatures were measured on the surface of Titan during the 2004–2014 portion of the
Cassini mission by the Composite Infrared Spectrometer. Temperatures mapped from pole to pole during five twoyear
periods show a marked seasonal dependence. The surface temperature near the south pole over this time
decreased by 2 K from 91.7±0.3 to 89.7±0.5 K while at the north pole the temperature increased by 1 K from
90.7±0.5 to 91.5±0.2 K. The latitude of maximum temperature moved from 19 S to 16 N, tracking the subsolar
latitude. As the latitude changed, the maximum temperature remained constant at 93.65±0.15 K. In 2010
our temperatures repeated the north–south symmetry seen by Voyager one Titan year earlier in 1980. Early in the
mission, temperatures at all latitudes had agreed with GCM predictions, but by 2014 temperatures in the north were
lower than modeled by 1 K. The temperature rise in the north may be delayed by cooling of sea surfaces and moist
ground brought on by seasonal methane precipitation and evaporation.
Dr. Kent Miller presents an overview of his program, Space Science, at the AFOSR 2013 Spring Review. At this review, Program Officers from AFOSR Technical Divisions will present briefings that highlight basic research programs beneficial to the Air Force.
1980 öncesi deprem istasyon sayısı Türkiye'de herhalde 50'den azdı ve bu nedenle deprem istatistiği çalışmaları Türkiye boyunca çok büyük alanlara bölünerek yapılmış. Okla gösterdiğim yerlerde magnitüd aralığı çok yetersiz. Bu çalışmada, 4x4 şeklinde dilimleme yapılmış. 400kmx400 km olarak dilimlere ayrılarak yapılmış. Veri olmadığı zaman mecbur ALANI büyütmek zorunda kalıyorsunuz... bu nedenle Makro-İstatistik İnceleme yapılmış oluyor.a/b oranını çalışmalarımda hiç kullanmadım fakat bana kalırsa yararlı bir parametre olarak görünüyor. Bir yıl içinde olması beklenen en büyük deprem büyüklüğünü veriyor. Buna göre bu çalışmada, bir yıl içinde beklenen en büyük deprem M=5 bulunmuş ve alan 39 E ve 41 B arasında bir yere denk geliyor... muhtemelen Karlıova Üçlü Bileşimi çevresi olabilir.
Meridional brightness temperatures were measured on the surface of Titan during the 2004–2014 portion of the
Cassini mission by the Composite Infrared Spectrometer. Temperatures mapped from pole to pole during five twoyear
periods show a marked seasonal dependence. The surface temperature near the south pole over this time
decreased by 2 K from 91.7±0.3 to 89.7±0.5 K while at the north pole the temperature increased by 1 K from
90.7±0.5 to 91.5±0.2 K. The latitude of maximum temperature moved from 19 S to 16 N, tracking the subsolar
latitude. As the latitude changed, the maximum temperature remained constant at 93.65±0.15 K. In 2010
our temperatures repeated the north–south symmetry seen by Voyager one Titan year earlier in 1980. Early in the
mission, temperatures at all latitudes had agreed with GCM predictions, but by 2014 temperatures in the north were
lower than modeled by 1 K. The temperature rise in the north may be delayed by cooling of sea surfaces and moist
ground brought on by seasonal methane precipitation and evaporation.
Dr. Kent Miller presents an overview of his program, Space Science, at the AFOSR 2013 Spring Review. At this review, Program Officers from AFOSR Technical Divisions will present briefings that highlight basic research programs beneficial to the Air Force.
1980 öncesi deprem istasyon sayısı Türkiye'de herhalde 50'den azdı ve bu nedenle deprem istatistiği çalışmaları Türkiye boyunca çok büyük alanlara bölünerek yapılmış. Okla gösterdiğim yerlerde magnitüd aralığı çok yetersiz. Bu çalışmada, 4x4 şeklinde dilimleme yapılmış. 400kmx400 km olarak dilimlere ayrılarak yapılmış. Veri olmadığı zaman mecbur ALANI büyütmek zorunda kalıyorsunuz... bu nedenle Makro-İstatistik İnceleme yapılmış oluyor.a/b oranını çalışmalarımda hiç kullanmadım fakat bana kalırsa yararlı bir parametre olarak görünüyor. Bir yıl içinde olması beklenen en büyük deprem büyüklüğünü veriyor. Buna göre bu çalışmada, bir yıl içinde beklenen en büyük deprem M=5 bulunmuş ve alan 39 E ve 41 B arasında bir yere denk geliyor... muhtemelen Karlıova Üçlü Bileşimi çevresi olabilir.
Greetings all,
Nowadays, several datasets are -or will be- available in a near future to improve operational forecasting in most aspects, like the
ocean dynamics modeling, and the assimilation efficiency, that aims now to optimize the combination of temperature/salinity in
situ profiles, drifter's velocities, and sea surface height deduce from altimeter's data and GRACE or future Goce geoid. But also
strengthen forecasting system's applications, like the climate monitoring. For all these issues, an optimal use of ocean data,
always too sparse and not enough numerous, is mandatory.
Such studies are at the heart of this Newsletter issue. It begins with a Rio M.H. and Hernandez F. review of the Goce Mission,
dedicated to focus and document the shortest scales of the Earth's gravity field. Goce satellite is due to fly in December 2007.
With the next article Guinéhut S. and Larnicol G. investigate the influence of the in situ temperature profiles sampling on the
thermosteric sea level estimation. They show that the impact is not negligible, and can introduce large errors in the estimation. In
the second article, Benkiran M. and Greiner E. are evaluating the benefits of the drifter's velocities assimilation in the Mercator
Océan 1/3° Tropical and North Atlantic operational system. A description of the assimilation scheme upgrade to take into account
velocity control is given. Castruccio F. & al. describe in the third article the performance of an improved MDT reference for
altimetric data assimilation. They concentrate their study on the Tropical Pacific Ocean. Finally, the Newsletter comes to an end
with the Benkiran M. article. In his study, based on the 1/3° Mercator system, the impact of several altimeters data on the
assimilation performance is assessed
Have a good read
A Possible Relationship between Gravitational Variations and Earthquakes in C...inventionjournals
An earthquake is not simply a sudden movement of the earth's crust, but the final product of a process that may have begun much earlier. In an area subject to tectonic stress, there can be precursory phenomena since this is where crustal deformation accumulates. A variation in gravity, measured instrumentally to the sixth decimal place, is one of the possible candidates to analyse measurable signals that precede, accompany and follow a seismic tremor. To verify the relationship between the number of earthquakes, the energy released, and the variations in gravity, the sequence in Central Italy was examined, above all that of January 2017. Data from a gravimeter located about 270 kilometres from the epicentral areas have been modelled as Standard Deviation, obtained from gravity measurements (400) carried out on the respective days. This indicator, of a statistical and mathematical nature, indicates the degree of dispersion with respect to its mean value, taken as the average value of these gravity measurements, and shows a positive correlation with the number of daily earthquakes and the energy released by the seismic sequence of January 2017.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Estimating the Atlantic overturning at 26N using satellite altimetry [IUGG]Eleanor Frajka-Williams
See http://eleanorfrajka.com/moc-from-space/ Slides from IUGG meeting in Prague: Estimating the Atlantic overturning circulation at 26N from satellite altimetry.
Greetings all,
Nowadays, several datasets are -or will be- available in a near future to improve operational forecasting in most aspects, like the
ocean dynamics modeling, and the assimilation efficiency, that aims now to optimize the combination of temperature/salinity in
situ profiles, drifter's velocities, and sea surface height deduce from altimeter's data and GRACE or future Goce geoid. But also
strengthen forecasting system's applications, like the climate monitoring. For all these issues, an optimal use of ocean data,
always too sparse and not enough numerous, is mandatory.
Such studies are at the heart of this Newsletter issue. It begins with a Rio M.H. and Hernandez F. review of the Goce Mission,
dedicated to focus and document the shortest scales of the Earth's gravity field. Goce satellite is due to fly in December 2007.
With the next article Guinéhut S. and Larnicol G. investigate the influence of the in situ temperature profiles sampling on the
thermosteric sea level estimation. They show that the impact is not negligible, and can introduce large errors in the estimation. In
the second article, Benkiran M. and Greiner E. are evaluating the benefits of the drifter's velocities assimilation in the Mercator
Océan 1/3° Tropical and North Atlantic operational system. A description of the assimilation scheme upgrade to take into account
velocity control is given. Castruccio F. & al. describe in the third article the performance of an improved MDT reference for
altimetric data assimilation. They concentrate their study on the Tropical Pacific Ocean. Finally, the Newsletter comes to an end
with the Benkiran M. article. In his study, based on the 1/3° Mercator system, the impact of several altimeters data on the
assimilation performance is assessed
Have a good read
A Possible Relationship between Gravitational Variations and Earthquakes in C...inventionjournals
An earthquake is not simply a sudden movement of the earth's crust, but the final product of a process that may have begun much earlier. In an area subject to tectonic stress, there can be precursory phenomena since this is where crustal deformation accumulates. A variation in gravity, measured instrumentally to the sixth decimal place, is one of the possible candidates to analyse measurable signals that precede, accompany and follow a seismic tremor. To verify the relationship between the number of earthquakes, the energy released, and the variations in gravity, the sequence in Central Italy was examined, above all that of January 2017. Data from a gravimeter located about 270 kilometres from the epicentral areas have been modelled as Standard Deviation, obtained from gravity measurements (400) carried out on the respective days. This indicator, of a statistical and mathematical nature, indicates the degree of dispersion with respect to its mean value, taken as the average value of these gravity measurements, and shows a positive correlation with the number of daily earthquakes and the energy released by the seismic sequence of January 2017.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Estimating the Atlantic overturning at 26N using satellite altimetry [IUGG]Eleanor Frajka-Williams
See http://eleanorfrajka.com/moc-from-space/ Slides from IUGG meeting in Prague: Estimating the Atlantic overturning circulation at 26N from satellite altimetry.
its a small view of layers of atmosphere! maximum every person have to know this type of information etiher they're engineer, doctor or accountant! it's a basic for our lives!
This was my presentation for my grand demonstration teaching. If you want to see my lesson plan for this topic just click the link. http://www.slideshare.net/ubuntu0125/detailed-lesson-plan-earths-atmosphere
This presentations covers composition of air ,layers of atmosphere.If you like this presentation please give it a like .
for more interesting presentations visit my page - http://allfactsatonce.blogspot.in/
Study of Average Hourly Variations of Radio Refractivity Variations across So...iosrjce
The results of the diurnal variation of refractivity based on measurement of atmospheric pressure,
temperature and relative humidity made across some selected locations within Nigeria, Yola (90
11' N, 120
30'
E), Anyigba (70
45' N, 60
45' E), Lagos (60
27' N, 50
12' E), and Port-Harcourt (40
48'N, 70E), is presented in this
study. The study utilized three years of meteorological data measured from January 2010 to December 2013
using Vantage Pro 2 automatic weather station installed at each location. The average hourly variations of
refractivity in the dry season is largely as a result of the variations of the wet component (humidity) while the
average daily variations of surface radio refractivity in the rainy season is as a result of both the variations of
the dry (pressure) and wet (humidity) component of surface radio refractivity. It also observed that the values of
surface radio refractivity showed seasonal variations with high value during rainy season and low values
during dry season with an increase in the value of surface radio refractivity from minimum value of about
242N-units at Anyigba station to maximum value of about 384-N units at Lagos station. The diurnal variation of
refractivity of the troposphere is a function of local meteorology as observed from results obtained from the
study.
Water vapor mapping on mars using omega mars expressAwad Albalwi
A systematic mapping of water vapor on Mars has been achieved using the imaging spectrometer OMEGA aboard the Mars Express
spacecraft, using the depth of the 2.6 mm (n1, n3) band of H2O. We report results obtained during two periods: (1) Ls ¼ 330–401
(January–June 2004), before and after the equinox, and (2) Ls ¼ 90–1251, which correspond to early northern summer
First Observation of the Earth’s Permanent FreeOscillation s on Ocean Bottom ...Sérgio Sacani
The Earth’s hum is the permanent free oscillations of the Earth recorded in the absence ofearthquakes, at periods above 30 s. We present the first observations of its fundamental spheroidaleigenmodes on broadband ocean bottom seismometers (OBSs) in the Indian Ocean. At the ocean bottom,the effects of ocean infragravity waves (compliance) and seafloor currents (tilt) overshadow the hum. In ourexperiment, data are also affected by electronic glitches. We remove these signals from the seismic traceby subtracting average glitch signals; performing a linear regression; and using frequency-dependentresponse functions between pressure, horizontal, and vertical seismic components. This reduces the longperiod noise on the OBS to the level of a good land station. Finally, by windowing the autocorrelation toinclude only the direct arrival, the first and second orbits around the Earth, and by calculating its Fouriertransform, we clearly observe the eigenmodes at the ocean bottom.
Disturbances in Solar Wind Electrons during the Ascending Half of the Solar C...researchinventy
Ulysses achieved a solar orbit with an inclination of 80.200 , perihelion of 1.34 AU, aphelion of 5.4 AU and a period of 6.2 years. By comparing observations taken over nearly all heliolatitudes and two different intervals covering the same radial distances, we are able to separate the radial and latitudinal variations in the solar wind. This paper describes the detailed results of the studies devoted to the solar activity impact on the Earth’s upper atmosphere and ionosphere. The methods used in this study are based on the data driven from the Ulysses spacecraft. The primary objective of the Ulysses solar wind plasma investigation uses SWOOPS (Solar Wind Observations over the Poles of the Sun) instrument to investigate and establish bulk flow parameters and internal state conditions of the solar wind as a function of solar latitude. The electron temperature Te and the electron density Ne are found to exhibit a sharp enhancement during the ascending half of the solar cycle 23 (1996 – 2004)
Direct Measure of Radiative And Dynamical Properties Of An Exoplanet AtmosphereSérgio Sacani
Two decades after the discovery of 51Pegb, the formation processes and atmospheres of short-period gas giants
remain poorly understood. Observations of eccentric systems provide key insights on those topics as they can
illuminate how a planet’s atmosphere responds to changes in incident flux. We report here the analysis of multi-day
multi-channel photometry of the eccentric (e ~ 0.93) hot Jupiter HD80606b obtained with the Spitzer Space
Telescope. The planet’s extreme eccentricity combined with the long coverage and exquisite precision of new
periastron-passage observations allow us to break the degeneracy between the radiative and dynamical timescales
of HD80606b’s atmosphere and constrain its global thermal response. Our analysis reveals that the atmospheric
layers probed heat rapidly (∼4 hr radiative timescale) from<500 to 1400 K as they absorb ~20% of the incoming
stellar flux during the periastron passage, while the planet’s rotation period is 93 35
85
-
+ hr, which exceeds the predicted
pseudo-synchronous period (40 hr).
Key words: methods: numerical – planet–star interactions – planets and satellites: atmospheres – planets and
satellites: dynamical evolution and stability – planets and satellites: individual (HD 80606 b) – techniques:
photometric
The Internal Structure of Asteroid (25143) Itokawa as Revealed by Detection o...
SRS2015-Pugmire
1. Observations of mesospheric
gravity waves over the andes
Jonathan Pugmire
Center for Atmospheric and Space Sciences
Utah State University
Student Research Symposium
April 9, 2015
17. 0 60 120 180 240 300 360
0
10
20
30
TemperatureVariance(K2
)
Day
– 87 km
– 67 km
– 42 km
2010 temperature variances over
the Andes
87 km average: 9.6 K2
WinterIncreased wave activity observed
from space during the winter
along with fall and spring
20. References
• Eckerman, S.D. and P. Preusse (1999), Global Measurements of Stratospheric Mountain Waves from Space, Science,
286, 5444, 1534-1537.
• Fritts, D.C., and M.J. Alexander (2003), Gravity wave dynamics and effects in the middle atmosphere. Review of
Geophysics, 41, 1/1003.
• Goldman, A., Schoenfeld, W.G., Goorvitch, D., Chackerian Jr., C., Dothe, H., Me1en, F., Abrams, M.C., Selby, J.E.A.
(1998), Updated line parameters for the OH X2 П -X2П (v",v') transitions. J. Quant. Spectrosc. Radiat. Transfer, 59,
453-469.
• Jiang, J. H., Wu, D. L., & Eckermann, S. D. (2002). Upper Atmosphere Research Satellite (UARS) MLS observation of
mountain waves over the Andes.Journal of Geophysical Research: Atmospheres (1984–2012), 107(D20), SOL-15.
• John, S.R., and Kumar, K.K. (2012), TIMED/SABER observations of global gravity wave climatology and their
interannual variability from stratosphere to mesosphere lower thermosphere, Climate dynamics, 39(6), 1489-1505
• Meriwether, J.W. (1984), Ground based measurements of mesospheric temperatures by optical means. MAP
Handbook 13, 1-18.
• Pendleton Jr., W.R., Taylor, M.J., Gardner, L.C. (2000), Terdiurnal oscillations on OH Meinel rotational temperatures
for fall conditions at northern mid-latitude sites. GRL 27 (12), 1799-1802.
• Reisin, E. R., & Scheer, J. (2004), Gravity wave activity in the mesopause region from airglow measurements at El
Leoncito. Journal of Atmospheric and Solar-Terrestrial Physics, 66(6), 655-661.
• Remsberg, E. E., et al. (2008), Assessment of the quality of the Version 1.07 temperature-versus-pressure profiles of
the middle atmosphere from TIMED/SABER, J. Geophys. Res., 113, D17101, doi:10.1029/2008JD010013.
• Russell III, James M., et al. 1999, Overview of the SABER experiment and preliminary calibration results. SPIE's
International Symposium on Optical Science, Engineering, and Instrumentation. International Society for Optics and
Photonics Conference
• Taori, A. and M.J. Taylor (2006), Characteristics of wave induced oscillations in mesospheric O2 emission intensity and
temperature, Geophys. Res. Lett., 33.
• Zhao, Y., M. J. Taylor, and X. Chu (2005), Comparison of simultaneous Na lidar and mesospheric nightglow
temperature measurements and the effects of tides on the emission layer heights, J. Geophys. Res., 110, D09S07,
doi:10.1029/2004JD005115.
• Zhao, Y., Taylor, M.J., Liu, H.-L., Roble, R.G. (2007), Seasonal oscillations in mesospheric temperatures at low-
latitudes. JASTP 69, 2367-2378.
24. OH Rotational Temperature
OH (6,2) Band
))]4(/)2((ln[ 11 PPstuff
SomeNumber
TOH
Goldman et al., 1998
2 K Precision
25. Step 3: At each height estimate waves
with wavenumber 0-6.
26. Step 3: At each height estimate waves
with wavenumber 1.
27. Step 3: At each height estimate waves
with wavenumber 2.
28. Step 3: At each height estimate waves
with wavenumber 3.
29. Step 3: At each height estimate waves
with wavenumber 0-6.
Editor's Notes
Atmosphere is “Stable”
Wind is perpendicular to mountain range
Strong winds
Stably stratified air that is lifted over mountains oscillates about its equilibrium level on the lee side of the mountain, producing waves.
Vertically propagating mountain waves have their highest amplitude well above the mountains. High lenticular clouds are often indicated of these waves.
Trapped less waves reach their highest amplitudes in the lee of mountains.
The above discussed equations of motion predict that vertical displacement of a flow almost always leads to the generation of AGWs. Terrain-generated gravity waves are created when stably stratified wind flows over terrain obstacles such as ridges, hills and mountains as well as depressions such as canyons, basins and valleys. Two types of terrain-generated waves exist: lees waves and mountain waves. Lee waves extend downwind from the ridge and are trapped in a layer close to the ground, and so their influence of the atmosphere above is negligible. Mountain waves (MWs) or orographically forced waves are terrain-generated gravity waves that propagate towards the middle and upper atmosphere transporting energy and momentum. This is an essential component of the global circulation. The spectrum of MWs is as wide as the spectrum of terrain widths. The amplitudes of MWs are proportional to the amplitude of the terrain as illustrated in Figure 4.
MWs are stationary relative to the ground surface, and they do not experience dispersion. All the waves have the same phase velocity, which is zero. Thus standing waves develop and amplitude of the mountain wave can grow as they move upward and eventually break or saturate. This breakdown, like waves on a beach, results in turbulence, commonly referred to as clear air turbulence (CAT) as shown in Figure 5.
MWs are stationary relative to the ground surface, and they do not experience dispersion. All the waves have the same phase velocity, which is zero. Thus standing waves develop and amplitude of the mountain wave can grow as they move upward and eventually break or saturate. This breakdown, like waves on a beach, results in turbulence, commonly referred to as clear air turbulence (CAT) as shown in Figure 5.
Stably stratified air that is lifted over mountains oscillates about its equilibrium level on the lee side of the mountain, producing waves.
Vertically propagating mountain waves have their highest amplitude well above the mountains. High lenticular clouds are often indicated of these waves.
Trapped less waves reach their highest amplitudes in the lee of mountains.
The above discussed equations of motion predict that vertical displacement of a flow almost always leads to the generation of AGWs. Terrain-generated gravity waves are created when stably stratified wind flows over terrain obstacles such as ridges, hills and mountains as well as depressions such as canyons, basins and valleys. Two types of terrain-generated waves exist: lees waves and mountain waves. Lee waves extend downwind from the ridge and are trapped in a layer close to the ground, and so their influence of the atmosphere above is negligible. Mountain waves (MWs) or orographically forced waves are terrain-generated gravity waves that propagate towards the middle and upper atmosphere transporting energy and momentum. This is an essential component of the global circulation. The spectrum of MWs is as wide as the spectrum of terrain widths. The amplitudes of MWs are proportional to the amplitude of the terrain as illustrated in Figure 4.
MWs are stationary relative to the ground surface, and they do not experience dispersion. All the waves have the same phase velocity, which is zero. Thus standing waves develop and amplitude of the mountain wave can grow as they move upward and eventually break or saturate. This breakdown, like waves on a beach, results in turbulence, commonly referred to as clear air turbulence (CAT) as shown in Figure 5.
Airglow – camera looks in the infrared. Each molecules produces light that is a distinct color or wavelength. Hydroxyl, OH, has a distinct signature.
ALO, Chile
UT Day 258 2012 (LT September 13 - 14 dt = -4 hrs)
MWFM is a parameterization that operates diagnostically on gridded atmospheric winds and temperatures. A key feature is the decomposition of global topography into a
list of quasi-two-dimensional ridges, each with a characteristic width, length, height, horizontal orientation and quality (degree of two-dimensionality) that define the types of
mountain waves forced by directional flow over the feature. Surface winds blowing over these ridges are used to calculate the spectrum of mountain waves at the surface.
From November 2001 to December 2006 the MTM instrument suite operated from the Air Force AMOS facility near the summit of Haleakala Crater, Maui, Hawaii (altitude 2970 m, 20.8°N, 156.2° W) [Zhao et al., 2005]. Temperature comparisons with the MTM and SABER were conducted from Maui. The MTM in Maui had an average temperature of 202.2 K and SABER’s average temperature was 197.0 K. They had a similar difference of 5.2 ± 0.2 K. What is of interest is the amount of variation that is apparent at ALO as opposed to Maui. The temperature difference between SABER and ALO measurements had a standard deviation of 16.9 K, where Maui’s had a standard deviation 8.9 K. This may be due to the increased mountain wave activity observed at ALO. This is shown in the two histograms in Figure 8 with Gaussian fits. Further investigation of evidence of mountain wave activity is ongoing.
87 km : 9.6, 67 km average: 3.54K^2, 42 km average 0.86
Mountain waves in the mesosphere are a relatively unexplored field.
Temperature variances increase due to mountain waves in winter and other sources in spring/fall.
SABER temperature variance technique has high potential for investigating gravity wave effects with other ground-based measurements around the world.
Use SABER data measure temperature variance to observe vertical propagation of mountain waves and study under what conditions they break or saturate.
Compare SABER measurements with ground-based observations of mountain waves over the Andes: July 1-8, 2008, July 22-23, 2011.
Use SABER to study other locations (Maui, Bear Lake, New Zealand, etc.) for quantitative ground-based comparison of mountain wave activity.
Use SABER data measure temperature variance to observe vertical propagation of mountain waves and study under what conditions they break or saturate.
Compare SABER measurements with ground-based observations of mountain waves over the Andes: July 1-8, 2008, July 22-23, 2011.
Use SABER to study other locations (Maui, Bear Lake, New Zealand, etc.) for quantitative ground-based comparison of mountain wave activity.
Wave phenomena are prevalent in planetary atmospheres and are a result of perturbations. They are induced by both external and internal sources. Waves can be classified into two main groups based on the spatial scale length of the wave. There are large scale waves known as planetary waves and tides. They are both global in nature and exhibit coherent patterns in both latitude and longitude. Planetary waves are caused by the coriolis effect. Tides have to do with solar radiation.
On a smaller scale atmospheric gravity waves (AGW) are generated due to buoyancy forces in the atmosphere. AGW usually have local sources and propagate with limited range of wavelengths. The sources of AGW are in the stratosphere and mesosphere and they propagate into the thermosphere. AGW can also be generated from thunderstorms, volcanoes, earthquakes, the jetstream, and the flow of air over mountains. They can also be generated at high altitudes. AGW have been studied for the last 50 years starting with the pioneering work of Hines (1960) and the study continues to intensify with quantitative advances in our understanding of AGW and advances in observational and computational techniques and capabilities. AGWs have a myriad of effects and are major contributors to atmospheric circulation, structure, and variability.
Ship waves… Amsterdam Island in the far southern Indian Ocean
All-sky imager, OH June 11, 2010, 300km by 300km
Figure 3. Emissions given by different OH vibrational mode transitions. The ratio of the P1(2) to P1(4) emissions (highlighted in red) is used to measure OH rotational temperature.
To date, over 1100 nights of quality data have been obtained, providing detailed information on the nocturnal and seasonal behavior of mesospheric temperature and its variability at the OH emission height.
Relative intensity measurements of the selected OH emission lines are used to determine absolute rotational temperatures with high precision ~1-2 K using the well-established ratio method [e.g. Meriwether, 1984, Goldman et al., 1998]. Based on typical OH emission levels measured at Cerro Pachon, the precision of the measurements were determined to be <1-2 K (in 2 min) for the derived OH rotational temperatures.
Relative band intensity from (S1c+S2c) and Temperature using simplified Local Thermodynamic Equalibrium calculation.
Figure 2. Picture of all-sky imaging system. Fish eye lens at top, followed by filter wheel. CCD imager and cooling system are positioned at bottom.
The CEDAR MTM is a high performance imaging system capable of precise measurement of the intensity and rotational temperatures of the near infrared OH and O2 nightglow emission layers. The MTM uses a high quantum efficiency CCD array coupled to a wide-angle telecentric lens system (90° field of view centered on the zenith) to observe selected emission lines in the OH(6,2) Meinel band as shown in Figure 3. Sequential measurements were made using a set of narrow band filters centered on selected emission lines, eg. the OH(6,2) P1(2) and P1(4) rotational emission lines at 840 and 846.5 nm respectively. Each emission is observed for 30 sec followed by a background sky measurement at 857 nm, resulting in a cycle time of ~2 min. The camera operates automatically from dusk to dawn (for solar depression angles >12°) for approximately 23 nights each month (centered on the new moon period). Data are stored locally on computer disk and are downloaded at regular intervals to USU for analysis.