BibTex RIS Kaynak Göster

Seasonal and intraseasonal polar motion variability as deduced from atmospheric torques

Yıl 2012, Sayı: 106, 123 - 129, 01.12.2012
https://doi.org/10.9733/jgg.231112.1t

Öz

The main objective of this paper is to investigate the atmospheric excitation of seasonal and intraseasonal polar motion based on the so-called torque approach. For the period 2009–2011, we calculate the comprehensive set of equatorial torques acting on the solid Earth, which arise from pressure gradients at topographic features, frictional wind stresses, and mass-induced forces on the Earth’s equatorial bulge. The particular innovation of the study is to use the most recent and accurate meteorological reanalysis data of the ECMWF European Centre for Medium-Range Weather Forecasts and the NASA Global Modeling and Assimilation Office for reassessing the ability of atmospheric torques to explain geophysical signals in observed polar motion. Time domain and statistical comparisons suggest that the torque results are of the same quality as the corresponding values from the traditionally applied angular momentum approach. It is shown that the y component of polar motion variability is particularly well accounted for by torques that act over land areas, while the x component also strongly depends on oceanic excitation. A remarkable result is the excellent agreement of the two utilized atmospheric models in terms of torques on all time scales.

Kaynakça

  • Bell M.J., (1994), Oscillations in the equatorial components of the atmosphere’s angular momentum and torques on the earth’s bulge, Q. J. R. Meteorol. Soc., 120,195–213.
  • Bizouard C., Brzeziński A., Petrov S., (1998), Diurnal atmospheric forcing and temporal variations of the nutation amplitudes, J. Geod., 72,561–577.
  • Brzeziński A., (1994), Polar motion excitation by variations of the effective angular momentum function, II: extended-model, Manuscripta Geodetica, 19,157–171.
  • Chen J., Wilson C., (2005), Hydrological excitation of polar motion, 1993–2002, Geophys. J. Int., 160,833–839, doi: 10.1111/j.1365-246X.2005.02522.x.
  • Dee D.P. et al., (2011), The ERA-Interim reanalysis: configuration and performance of the data assimilation system, Q. J. R. Meteorol. Soc., 137,553–597, doi:10.1002/qj.828.
  • de Viron O., Dehant V., (1999), Earth’s rotation and high frequency equatorial angular momentum budget of the atmosphere, Surv. Geophys., 20,441–462.
  • de Viron O., Dehant V., (2003), Tests on the the validity of atmospheric torques on Earth computed from atmospheric model outputs, J. Geophys. Res., 108(B2),2068, doi: 10.1029/2001JB001196.
  • de Viron O., Bizouard C., Salstein D., Dehant V., (1999), Atmospheric torque on the Earth and comparison with atmospheric angular momentum variations, J. Geophys. Res., 104(B3),4861–4875, doi: 10.1029/1999JB900063.
  • de Viron O., Dickey J.O., Marcus, S.L. (2002), Annual atmospheric torques: Processes and regional contributions, Geophys. Res. Lett., 29(7),1140, doi: 10.1029/2001GL013859.
  • Dehant V., de Viron O., (2002), Earth rotation as an interdisciplinary topic shared by astronomers, geodesists and geophysicists, Adv. Space Res., 30(2),163–173.
  • Dobslaw H., Dill R., Grötzsch A., Brzeziński A., Thomas M., (2010), Seasonal polar motion excitation from numerical models of atmosphere, ocean and continental hydrosphere, J. Geophys. Res., 115(B10406), doi,10.1029/2009JB007127.
  • Egger J., Hoinka K.P., (2002), Equatorial components of global atmospheric angular momentum: Covariance functions, Q. J. R. Meteorol. Soc., 128,1137–1157.
  • Feldstein S., (2008), The dynamics of atmospherically driven intraseasonal polar motion, J. Atm. Sciences, 65(7),2290– 2307.
  • Fujita M., Chao B.F., Sanchez B.V., Johnson T.J., (2002), Oceanic torques on solid Earth and their effects on Earth rotation, J. Geophys. Res., 107(B7),2154, doi: 10.1029/2001JB000339.
  • Gambis D., (2012), Earth Orientation Center, Observatoire de Paris, http://hpiers.obspm.fr/eop-pc/, as at September 2012.
  • Gross R.S., Fukumori I., Menemenlis D., (2003), Atmospheric and oceanic excitation of the Earth’s wobbles during 1980–2000, J. Geophys. Res., 108(B8),2370, doi: 10.1029/2002JB002143.
  • Gross R.S., (2007), Earth rotation variations – long period, Treatise on Geophysics’in içinde, Vol. 3, Geodesy, (Herring T.A., Ed.), Elsevier, ss. 239–294.
  • Marcus S.L., de Viron O., Dickey, J.O., (2010), Interannual atmospheric torque and El-Niño-Southern Oscillation: Where is the polar motion signal?, J. Geophys. Res., 115(B12409), doi: 10.1029/2010JB007524.
  • Mendes Cerveira P., Böhm J., Schuh H., Klügel T., Velikoseltsev A., Schreiber U., Brzezinski A., (2009), Earth rotation observed by Very Long Baseline Interferometry and ring laser, Pure Appl. Geophys., 166, 1499–1517.
  • Munk W.H., MacDonald G.J.F., (1960), The Rotation of the Earth: A Geophysical Discussion, Cambridge University Press, New York.
  • Rienecker M.M. et al., (2011), MERRA – NASA’s Modern-Era Retrospective Reanalysis for Research and Applications, J. Climate, 24(17),3624–3648.
  • Rosen R.D., Salstein D.A., (1983), Variations in atmospheric angular momentum on global and regional scales and the length of day, J. Geophys. Res., 88(C9),5451–5470.
  • Schindelegger M., Böhm J., Salstein D., Schuh H., (2011), Highresolution angular momentum functions related to Earth rotation parameters during CONT08, J. Geod., 85(7),425–433, doi: 10.1007/s00190–011–0458–y.
  • Schindelegger M., Böhm S., Böhm J., Schuh H., (2013), Atmospheric Effects on Earth Rotation, Atmospheric Effects in Space Geodesy’nin içinde, (Böhm J., Schuh H., Ed.), Springer, baskıda.
  • Swinbank R., (1985), The global atmospheric angular momentum balance inferred from analyses made during FGGE, Quart. J. R. Met. Soc, 111,977–992.
  • Wahr J.M., (1982), The effects of the atmosphere and the oceans on the Earth’s wobble – I. Theory, Geophys. J. R. Astron. Soc., 70,349–372.
  • Wahr J.M., (1983), The effects of the atmosphere and the oceans on the Earth’s wobble and on the seasonal variations in the length of day – II. Results, J. R. Astron. Soc., 74,451–487.
  • White R.M., (1949), The role of the mountains in the angularmomentum balance of the atmosphere, J. Atmos. Sci., 6(5), 353–355.

Atmosferik torklardan elde edilen mevsimsel ve mevsim-içi kutup gezinmesi değişimleri

Yıl 2012, Sayı: 106, 123 - 129, 01.12.2012
https://doi.org/10.9733/jgg.231112.1t

Öz

Bu makalenin temel amacı mevsimsel ve mevsim-içi kutup gezinmesinin atmosferik eksitasyonunu tork yaklaşımı temelinde incelemektir. Bu çalışmada, 2009-2011 süresince, katı Yer’e etkiyen: topoğrafya üzerindeki atmosfer basınç gradyanlarını, rüzgar sürtünme gerilimlerini ve Yer’in ekvatoral bölgesine etkiyen atmosfer kitlesinin oluşturduğu kuvvetleri içeren bir dizi ekvatoral tork seti hesapladık. Bu çalışmanın kendine özgü yeniliği ise güncel ve duyarlığı yüksek ECMWF European Center for Medium-Range Weather Forecasts ve NASA Global Modeling and Assimilation Office meteorolojik analiz verileri kullanılarak ölçülen kutup gezinmeleri içerisindeki jeofizik sinyallerin atmosferik torklar ile açıklanabilme kabiliyetini ortaya koymaktır. Zaman uzayı ve istatistiksel karşılaştırmalar tork sonuçlarının geleneksel açısal momentum yaklaşımından elde edilen ilgili değerleri ile aynı kalitede olduğunu göstermektedir. Kutup gezinmesinin y bileşenindeki değişimlerin karalara etkiyen torklar ile iyi açıklanabildiği, x bileşeninin ise ayrıca okyanussal eksitasyona güçlü bir şekilde bağlı olduğu ortaya konulmuştur. Dikkate değer diğer bir sonuç ise faydalanılan iki atmosfer modelinden tüm zaman ölçekleri için elde edilen torkların mükemmel uyumudur

Kaynakça

  • Bell M.J., (1994), Oscillations in the equatorial components of the atmosphere’s angular momentum and torques on the earth’s bulge, Q. J. R. Meteorol. Soc., 120,195–213.
  • Bizouard C., Brzeziński A., Petrov S., (1998), Diurnal atmospheric forcing and temporal variations of the nutation amplitudes, J. Geod., 72,561–577.
  • Brzeziński A., (1994), Polar motion excitation by variations of the effective angular momentum function, II: extended-model, Manuscripta Geodetica, 19,157–171.
  • Chen J., Wilson C., (2005), Hydrological excitation of polar motion, 1993–2002, Geophys. J. Int., 160,833–839, doi: 10.1111/j.1365-246X.2005.02522.x.
  • Dee D.P. et al., (2011), The ERA-Interim reanalysis: configuration and performance of the data assimilation system, Q. J. R. Meteorol. Soc., 137,553–597, doi:10.1002/qj.828.
  • de Viron O., Dehant V., (1999), Earth’s rotation and high frequency equatorial angular momentum budget of the atmosphere, Surv. Geophys., 20,441–462.
  • de Viron O., Dehant V., (2003), Tests on the the validity of atmospheric torques on Earth computed from atmospheric model outputs, J. Geophys. Res., 108(B2),2068, doi: 10.1029/2001JB001196.
  • de Viron O., Bizouard C., Salstein D., Dehant V., (1999), Atmospheric torque on the Earth and comparison with atmospheric angular momentum variations, J. Geophys. Res., 104(B3),4861–4875, doi: 10.1029/1999JB900063.
  • de Viron O., Dickey J.O., Marcus, S.L. (2002), Annual atmospheric torques: Processes and regional contributions, Geophys. Res. Lett., 29(7),1140, doi: 10.1029/2001GL013859.
  • Dehant V., de Viron O., (2002), Earth rotation as an interdisciplinary topic shared by astronomers, geodesists and geophysicists, Adv. Space Res., 30(2),163–173.
  • Dobslaw H., Dill R., Grötzsch A., Brzeziński A., Thomas M., (2010), Seasonal polar motion excitation from numerical models of atmosphere, ocean and continental hydrosphere, J. Geophys. Res., 115(B10406), doi,10.1029/2009JB007127.
  • Egger J., Hoinka K.P., (2002), Equatorial components of global atmospheric angular momentum: Covariance functions, Q. J. R. Meteorol. Soc., 128,1137–1157.
  • Feldstein S., (2008), The dynamics of atmospherically driven intraseasonal polar motion, J. Atm. Sciences, 65(7),2290– 2307.
  • Fujita M., Chao B.F., Sanchez B.V., Johnson T.J., (2002), Oceanic torques on solid Earth and their effects on Earth rotation, J. Geophys. Res., 107(B7),2154, doi: 10.1029/2001JB000339.
  • Gambis D., (2012), Earth Orientation Center, Observatoire de Paris, http://hpiers.obspm.fr/eop-pc/, as at September 2012.
  • Gross R.S., Fukumori I., Menemenlis D., (2003), Atmospheric and oceanic excitation of the Earth’s wobbles during 1980–2000, J. Geophys. Res., 108(B8),2370, doi: 10.1029/2002JB002143.
  • Gross R.S., (2007), Earth rotation variations – long period, Treatise on Geophysics’in içinde, Vol. 3, Geodesy, (Herring T.A., Ed.), Elsevier, ss. 239–294.
  • Marcus S.L., de Viron O., Dickey, J.O., (2010), Interannual atmospheric torque and El-Niño-Southern Oscillation: Where is the polar motion signal?, J. Geophys. Res., 115(B12409), doi: 10.1029/2010JB007524.
  • Mendes Cerveira P., Böhm J., Schuh H., Klügel T., Velikoseltsev A., Schreiber U., Brzezinski A., (2009), Earth rotation observed by Very Long Baseline Interferometry and ring laser, Pure Appl. Geophys., 166, 1499–1517.
  • Munk W.H., MacDonald G.J.F., (1960), The Rotation of the Earth: A Geophysical Discussion, Cambridge University Press, New York.
  • Rienecker M.M. et al., (2011), MERRA – NASA’s Modern-Era Retrospective Reanalysis for Research and Applications, J. Climate, 24(17),3624–3648.
  • Rosen R.D., Salstein D.A., (1983), Variations in atmospheric angular momentum on global and regional scales and the length of day, J. Geophys. Res., 88(C9),5451–5470.
  • Schindelegger M., Böhm J., Salstein D., Schuh H., (2011), Highresolution angular momentum functions related to Earth rotation parameters during CONT08, J. Geod., 85(7),425–433, doi: 10.1007/s00190–011–0458–y.
  • Schindelegger M., Böhm S., Böhm J., Schuh H., (2013), Atmospheric Effects on Earth Rotation, Atmospheric Effects in Space Geodesy’nin içinde, (Böhm J., Schuh H., Ed.), Springer, baskıda.
  • Swinbank R., (1985), The global atmospheric angular momentum balance inferred from analyses made during FGGE, Quart. J. R. Met. Soc, 111,977–992.
  • Wahr J.M., (1982), The effects of the atmosphere and the oceans on the Earth’s wobble – I. Theory, Geophys. J. R. Astron. Soc., 70,349–372.
  • Wahr J.M., (1983), The effects of the atmosphere and the oceans on the Earth’s wobble and on the seasonal variations in the length of day – II. Results, J. R. Astron. Soc., 74,451–487.
  • White R.M., (1949), The role of the mountains in the angularmomentum balance of the atmosphere, J. Atmos. Sci., 6(5), 353–355.
Toplam 28 adet kaynakça vardır.

Ayrıntılar

Birincil Dil Türkçe
Bölüm Araştırma Makalesi
Yazarlar

Michael Schindelegger Bu kişi benim

Johannes Böhm Bu kişi benim

David Salstein Bu kişi benim

Yayımlanma Tarihi 1 Aralık 2012
Yayımlandığı Sayı Yıl 2012 Sayı: 106

Kaynak Göster

APA Schindelegger, M., Böhm, J., & Salstein, D. (2012). Atmosferik torklardan elde edilen mevsimsel ve mevsim-içi kutup gezinmesi değişimleri. Jeodezi Ve Jeoinformasyon Dergisi(106), 123-129. https://doi.org/10.9733/jgg.231112.1t
AMA Schindelegger M, Böhm J, Salstein D. Atmosferik torklardan elde edilen mevsimsel ve mevsim-içi kutup gezinmesi değişimleri. hkmojjd. Aralık 2012;(106):123-129. doi:10.9733/jgg.231112.1t
Chicago Schindelegger, Michael, Johannes Böhm, ve David Salstein. “Atmosferik Torklardan Elde Edilen Mevsimsel Ve Mevsim-içi Kutup Gezinmesi değişimleri”. Jeodezi Ve Jeoinformasyon Dergisi, sy. 106 (Aralık 2012): 123-29. https://doi.org/10.9733/jgg.231112.1t.
EndNote Schindelegger M, Böhm J, Salstein D (01 Aralık 2012) Atmosferik torklardan elde edilen mevsimsel ve mevsim-içi kutup gezinmesi değişimleri. Jeodezi ve Jeoinformasyon Dergisi 106 123–129.
IEEE M. Schindelegger, J. Böhm, ve D. Salstein, “Atmosferik torklardan elde edilen mevsimsel ve mevsim-içi kutup gezinmesi değişimleri”, hkmojjd, sy. 106, ss. 123–129, Aralık 2012, doi: 10.9733/jgg.231112.1t.
ISNAD Schindelegger, Michael vd. “Atmosferik Torklardan Elde Edilen Mevsimsel Ve Mevsim-içi Kutup Gezinmesi değişimleri”. Jeodezi ve Jeoinformasyon Dergisi 106 (Aralık 2012), 123-129. https://doi.org/10.9733/jgg.231112.1t.
JAMA Schindelegger M, Böhm J, Salstein D. Atmosferik torklardan elde edilen mevsimsel ve mevsim-içi kutup gezinmesi değişimleri. hkmojjd. 2012;:123–129.
MLA Schindelegger, Michael vd. “Atmosferik Torklardan Elde Edilen Mevsimsel Ve Mevsim-içi Kutup Gezinmesi değişimleri”. Jeodezi Ve Jeoinformasyon Dergisi, sy. 106, 2012, ss. 123-9, doi:10.9733/jgg.231112.1t.
Vancouver Schindelegger M, Böhm J, Salstein D. Atmosferik torklardan elde edilen mevsimsel ve mevsim-içi kutup gezinmesi değişimleri. hkmojjd. 2012(106):123-9.