Journal articles: 'Middle and low latitudes'

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Agnini, Claudia, Eliana Fornaciari, Isabella Raffi, Rita Catanzariti, Heiko Pälike, Jan Backman, and Domenico Rio. "Biozonation and biochronology of Paleogene calcareous nannofossils from low and middle latitudes." Newsletters on Stratigraphy 47, no. 2 (June 1, 2014): 131–81. http://dx.doi.org/10.1127/0078-0421/2014/0042.

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Chandran, A., and R. L. Collins. "Stratospheric sudden warming effects on winds and temperature in the middle atmosphere at middle and low latitudes: a study using WACCM." Annales Geophysicae 32, no. 7 (July 28, 2014): 859–74. http://dx.doi.org/10.5194/angeo-32-859-2014.

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Abstract. A stratospheric sudden warming (SSW) is a dynamical phenomenon of the wintertime stratosphere caused by the interaction between planetary Rossby waves propagating from the troposphere and the stratospheric zonal-mean flow. While the effects of SSW events are seen predominantly in high latitudes, they can also produce significant changes in middle and low latitude temperature and winds. In this study we quantify the middle and low latitude effects of SSW events on temperature and zonal-mean winds using a composite of SSW events between 1988 and 2010 simulated with the specified dynamics version of the Whole Atmosphere Community Climate Model (WACCM). The temperature and wind responses seen in the tropics also extend into the low latitudes in the other hemisphere. There is variability in observed zonal-mean winds and temperature depending on the observing location within the displaced or split polar vortex and propagation direction of the planetary waves. The propagation of planetary waves show that they originate in mid–high latitudes and propagate upward and equatorward into the mid-latitude middle atmosphere where they produce westward forcing reaching peak values of ~ 60–70 m s−1 day−1. These propagation paths in the lower latitude stratosphere appear to depend on the phase of the quasi-biennial oscillation (QBO). During the easterly phase of the QBO, waves originating at high latitudes propagate across the equator, while in the westerly phase of the QBO, the planetary waves break at ~ 20–25° N and there is no propagation across the equator. The propagation of planetary waves across the equator during the easterly phase of the QBO reduces the tropical upwelling and poleward flow in the upper stratosphere.

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Streltsov, A. V., and J. D. Huba. "Magnetospheric resonances at low and middle latitudes." Journal of Geophysical Research: Space Physics 120, no. 9 (September 2015): 7718–27. http://dx.doi.org/10.1002/2015ja021532.

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Haines, K. "Low-frequency variability in atmospheric middle latitudes." Surveys in Geophysics 15, no. 1 (January 1994): 1–61. http://dx.doi.org/10.1007/bf00665686.

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Jensen, J. W., and B. G. Fejer. "Longitudinal dependence of middle and low latitude zonal plasma drifts measured by DE-2." Annales Geophysicae 25, no. 12 (January 2, 2007): 2551–59. http://dx.doi.org/10.5194/angeo-25-2551-2007.

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Abstract. We used ion drift observations from the DE-2 satellite to study for the first time the longitudinal variations of middle and low latitude F region zonal plasma drifts during quiet and disturbed conditions. The quiet-time middle latitude drifts are predominantly westward; the low latitude drifts are westward during the day and eastward at night. The daytime quiet-time drifts do not change much with longitude; the nighttime drifts have strong season dependent longitudinal variations. In the dusk-premidnight period, the equinoctial middle latitude westward drifts are smallest in the European sector and the low latitude eastward drifts are largest in the American-Pacific sector. The longitudinal variations of the late night-early morning drifts during June and December solstice are anti-correlated. During geomagnetically active times, there are large westward perturbation drifts in the late afternoon-early night sector at upper middle latitudes, and in the midnight sector at low latitudes. The largest westward disturbed drifts during equinox occur in European sector, and the smallest in the Pacific region. These results suggest that during equinox SAPS events occur most often at European longitudes. The low latitude perturbation drifts do not show significant longitudinal

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Zhou, Yun-Liang, Li Wang, Chao Xiong, Hermann Lühr, and Shu-Ying Ma. "The solar activity dependence of nonmigrating tides in electron density at low and middle latitudes observed by CHAMP and GRACE." Annales Geophysicae 34, no. 4 (April 27, 2016): 463–72. http://dx.doi.org/10.5194/angeo-34-463-2016.

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Abstract. In this paper we use more than a decade of in situ electron density observations from CHAMP and GRACE satellites to investigate the solar activity dependence of nonmigrating tides at both low and middle latitudes. The results indicate that the longitudinal patterns of F region electron density vary with season and latitude, which are exhibiting a wavenumber 4 (WN4) pattern around September equinox at low latitudes and WN1/WN2 patterns during local summer at the southern/northern middle latitudes. These wave patterns in the F region ionosphere can clearly be seen during both solar maximum and minimum years. At low latitudes the absolute amplitudes of DE3 (contributing to the WN4 pattern) are found to be highly related to the solar activity, showing larger amplitudes during solar maximum years. Similarly a solar activity dependence can also be found for the absolute amplitudes of D0, DW2 and DE1 (contributing to the WN1 and WN2 pattern) at middle latitudes. The relative amplitudes (normalized by the zonal mean) of these nonmigrating tides at both low and middle altitudes show little dependence on solar activity. We further found a clear modulation by the quasi-biennial oscillation (QBO) of the relative DE3 amplitudes in both satellite observations, which is consistent with the QBO dependence as reported for the E region temperatures and zonal wind. It also supports the strong coupling of the low-latitude nonmigrating tidal activity between the E and F regions. However, the QBO dependence cannot be found for the relative amplitudes of the nonmigrating tides at middle latitudes, which implies that these tides are generated in situ at F region altitudes.

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Gulyaeva, T. L., S. Aggarwal, K. K. Mahajan, and S. Shastri. "Variability of foF2 at low and middle latitudes." Advances in Space Research 22, no. 6 (January 1998): 847–50. http://dx.doi.org/10.1016/s0273-1177(98)00110-0.

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8

Davies, K., and X. M. Liu. "Ionospheric slab thickness in middle and low latitudes." Radio Science 26, no. 4 (July 1991): 997–1005. http://dx.doi.org/10.1029/91rs00831.

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Backman, Jan, Isabella Raffi, Domenico Rio, Eliana Fornaciari, and Heiko Pälike. "Biozonation and biochronology of Miocene through Pleistocene calcareous nannofossils from low and middle latitudes." Newsletters on Stratigraphy 45, no. 3 (November 1, 2012): 221–44. http://dx.doi.org/10.1127/0078-0421/2012/0022.

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10

Andrioli, V. F., D. C. Fritts, P. P. Batista, B. R. Clemesha, and D. Janches. "Diurnal variation in gravity wave activity at low and middle latitudes." Annales Geophysicae 31, no. 11 (November 29, 2013): 2123–35. http://dx.doi.org/10.5194/angeo-31-2123-2013.

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Abstract. We employ a modified composite day extension of the Hocking (2005) analysis method to study gravity wave (GW) activity in the mesosphere and lower thermosphere using 4 meteor radars spanning latitudes from 7° S to 53.6° S. Diurnal and semidiurnal modulations were observed in GW variances over all sites. Semidiurnal modulation with downward phase propagation was observed at lower latitudes mainly near the equinoxes. Diurnal modulations occur mainly near solstice and, except for the zonal component at Cariri (7° S), do not exhibit downward phase propagation. At a higher latitude (SAAMER, 53.6° S) these modulations are only observed in the meridional component where we can observe diurnal variation from March to May, and semidiurnal, during January, February, October (above 88 km) and November. Some of these modulations with downward phase progression correlate well with wind shear. When the wind shear is well correlated with the maximum of the variances the diurnal tide has its largest amplitudes, i.e., near equinox. Correlations exhibiting variations with tidal phases suggest significant GW-tidal interactions that have different characters depending on the tidal components and possible mean wind shears. Modulations that do not exhibit phase variations could be indicative of diurnal variations in GW sources.

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Vriesema, J. W., T. T. Koskinen, and R. V. Yelle. "Electrodynamics in Saturn's thermosphere at low and middle latitudes." Icarus 344 (July 2020): 113390. http://dx.doi.org/10.1016/j.icarus.2019.113390.

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12

Chen, Y., L. Liu, W. Wan, and Z. Ren. "Equinoctial asymmetry in solar activity variations of <I>Nm</I>F2 and TEC." Annales Geophysicae 30, no. 3 (March 27, 2012): 613–22. http://dx.doi.org/10.5194/angeo-30-613-2012.

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Abstract. The ionosonde NmF2 data (covering several solar cycles) and the JPL TEC maps (from 1998 through 2009) were collected to investigate the equinoctial asymmetries in ionospheric electron density and its variation with solar activity. With solar activity increasing, the equinoctial asymmetry of noontime NmF2 increases at middle latitudes but decreases or changes little at low latitudes, while the equinoctial asymmetry of TEC increases at all latitudes. The latitudinal feature of the equinoctial asymmetry at high solar activity is different from that at low solar activity. The increases of NmF2 and TEC with the solar proxy P = (F10.7+F10.7A)/2 also show equinoctial asymmetries that depend on latitudes. The increase rate of NmF2 with P at March equinox (ME) is higher than that at September equinox (SE) at middle latitudes, but the latter is higher than the former at the EIA crest latitudes, and the difference between them is small at the EIA trough latitudes. The phenomenon of higher increase rate at SE than at ME does not appear in TEC. The increase rate of noontime TEC with P at ME is higher than that at SE at all latitudes, and the difference between them peaks at both sides of dip equator. It is mentionable that the equinoctial asymmetries of NmF2 and TEC increase rates present some longitudinal dependence at low latitude. The influences of equinoctial differences in the thermosphere and ionospheric dynamics processes on the equinoctial asymmetry of the electron density were briefly discussed.

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Zhang, Jing-Xue, Ming-Hui Chen, Lu Gan, Chuan-Jie Zhang, Yu Shen, Jin Qian, Meng-Li Han, Yu-Xia Guo, and Xue-Bing Yan. "Diversity Patterns of Bermuda Grass along Latitudinal Gradients at Different Temperatures in Southeastern China." Plants 9, no. 12 (December 15, 2020): 1778. http://dx.doi.org/10.3390/plants9121778.

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Cynodon dactylon (L.) Pers. (common Bermuda grass) has a limited capacity to grow at low temperatures, which limits its geographical range. Exploring its evolutionary relationship across different environmental gradients is necessary to understand the effects of temperature change on the genetics of common Bermuda grass. In this study, high-throughput transcriptome sequencing was performed on 137 samples of C. dactylon from 16 latitudinal gradients to explore the differential molecular markers and analyze genetic diversity and structure along latitudinal gradients at different temperatures. We primarily sampled more high-quality single nucleotide polymorphisms (SNPs) from populations at lower and middle latitudes. Greater intraspecific genetic variation at each level of temperature treatment could be due to factors such as wind pollination and asexual breeding. Populations of C. dactylon at high latitudes differed from populations at middle and low latitudes, which was supported by a principal component analysis (PCA) and genetic structure analysis, performed at different temperatures. We observed more genetic variation for low-latitude populations at 5 °C, according to an analysis of three phylogenetic trees at different temperature levels, suggesting that low temperatures affected samples with low cold resistance. Based on the results of phylogenetic analysis, we found that samples from high latitudes evolved earlier than most samples at low latitudes. The results provide a comprehensive understanding of the evolutionary phenomenon of landscape genetics, laying the groundwork for future structural and comparative genomic studies of C. dactylon.

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Lu, Xinmin, Minyan He, Saichun Tang, Yuqing Wu, Xu Shao, Hui Wei, Evan Siemann, and Jianqing Ding. "Herbivory may promote a non-native plant invasion at low but not high latitudes." Annals of Botany 124, no. 5 (July 18, 2019): 819–27. http://dx.doi.org/10.1093/aob/mcz121.

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Abstract Background and Aims The strengths of biotic interactions such as herbivory are expected to decrease with increasing latitude for native species. To what extent this applies to invasive species and what the consequences of this variation are for competition among native and invasive species remain unexplored. Here, herbivore impacts on the invasive plant Alternanthera philoxeroides and its competition with the native congener A. sessilis were estimated across latitudes in China. Methods An common garden experiment spanning ten latitudinal degrees was conducted to test how herbivore impacts on A. philoxeroides and A. sessilis, and competition between them change with latitude. In addition, a field survey was conducted from 21°N to 36.8°N to test whether A. philoxeroides invasiveness changes with latitude in nature as a result of variations in herbivory. Key Results In the experiment, A. sessilis cover was significantly higher than A. philoxeroides cover when they competed in the absence of herbivores, but otherwise their cover was comparable at low latitude. However, A. philoxeroides cover was always higher on average than A. sessilis cover at middle latitude. At high latitude, only A. sessilis emerged in the second year. Herbivore abundance decreased with latitude and A. philoxeroides emerged earlier than A. sessilis at middle latitude. In the field survey, the ratio of A. philoxeroides to A. sessilis cover was hump shaped with latitude. Conclusion These results indicate that herbivory may promote A. philoxeroides invasion only at low latitude by altering the outcome of competition in favour of the invader and point to the importance of other factors, such as earlier emergence, in A. philoxeroides invasion at higher latitudes. These results suggest that the key factors promoting plant invasions might change with latitude, highlighting the importance of teasing apart the roles of multiple factors in plant invasions within a biogeographic framework.

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Seyoum, Alene, Nat Gopalswamy, Melessew Nigussie, and Nigusse Mezgebe. "The impact of CMEs on the critical frequency of F2-layer ionosphere (foF2)." Proceedings of the International Astronomical Union 15, S356 (October 2019): 400–402. http://dx.doi.org/10.1017/s1743921320003579.

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AbstractThe ionospheric critical frequency (foF2) from ionosonde measurements at geographic high, middle, and low latitudes are analyzed with the occurrence of coronal mass ejections (CMEs) in long term variability of the solar cycles. We observed trends of monthly maximum foF2 values and monthly averaged values of CME parameters such as speed, angular width, mass, and kinetic energy with respect to time. The impact of CMEs on foF2 is very high at high latitudes and low at low latitudes. The time series for monthly maximum foF2 and monthly-averaged CME speed are moderately correlated at high and middle latitudes.

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16

Schröder, W. "The development of the aurora of 18 January 1770." History of Geo- and Space Sciences 1, no. 1 (June 4, 2010): 45–48. http://dx.doi.org/10.5194/hgss-1-45-2010.

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Abstract. The development of the great aurora of 18 January 1770 has been discussed in fundamental papers by Silberschlag, Behn and other authors. The aurora was observed in middle and low latitudes and in Northern latitude. In Central Europe it displayed all typical auroral forms, including the corona.

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Zhang, S. D., C. M. Huang, K. M. Huang, F. Yi, Y. H. Zhang, Y. Gong, and Q. Gan. "Spatial and seasonal variability of medium- and high-frequency gravity waves in the lower atmosphere revealed by US radiosonde data." Annales Geophysicae 32, no. 9 (September 12, 2014): 1129–43. http://dx.doi.org/10.5194/angeo-32-1129-2014.

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Abstract. We extended the broad spectral method proposed by Zhang et al. (2013) for the extraction of medium- and high-frequency gravity waves (MHGWs). This method was applied to 11 years (1998–2008) of radiosonde data from 92 stations in the Northern Hemisphere to investigate latitudinal, continuous vertical and seasonal variability of MHGW parameters in the lower atmosphere (2–25 km). The latitudinal and vertical distributions of the wave energy density and horizontal momentum fluxes as well as their seasonal variations exhibit considerable consistency with those of inertial gravity waves. Despite the consistency, the MHGWs have much larger energy density, horizontal momentum fluxes and wave force, indicating the more important role of MHGWs in energy and momentum transportation and acceleration of the background. For the observed MHGWs, the vertical wavelengths are usually larger than 8 km; the horizontal wavelengths peak in the middle troposphere at middle–high latitudes. These characteristics are obviously different from inertial gravity waves. The energy density and horizontal momentum fluxes have similar latitude-dependent seasonality: both of them are dominated by a semiannual variation at low latitudes and an annual variation at middle latitudes; however at high latitudes, they often exhibit more than two peaks per year in the troposphere. Compared with the inertial GWs, the derived intrinsic frequencies are more sensitive to the spatiotemporal variation of the buoyancy frequency, and at all latitudinal regions they are higher in summer. The wavelengths have a weaker seasonal variation; an evident annual cycle can be observed only at middle latitudes.

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18

Olsen, Nils. "IonosphericFregion currents at middle and low latitudes estimated from Magsat data." Journal of Geophysical Research: Space Physics 102, A3 (March 1, 1997): 4563–76. http://dx.doi.org/10.1029/96ja02949.

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19

Tsunomura, Satoru. "Characteristics of geomagnetic sudden commencement observed in middle and low latitudes." Earth, Planets and Space 50, no. 9 (September 1998): 755–72. http://dx.doi.org/10.1186/bf03352168.

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Karunatillake, S., J. J. Wray, O. Gasnault, S. M. McLennan, A. D. Rogers, S. W. Squyres, W. V. Boynton, J. R. Skok, L. Ojha, and N. Olsen. "Sulfates hydrating bulk soil in the Martian low and middle latitudes." Geophysical Research Letters 41, no. 22 (November 22, 2014): 7987–96. http://dx.doi.org/10.1002/2014gl061136.

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21

Alpers, M., J. Höffner, and U. von Zahn. "Sporadic Fe and E layers at polar, middle, and low latitudes." Journal of Geophysical Research 99, A8 (1994): 14971. http://dx.doi.org/10.1029/94ja00589.

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22

Wei, Lehui, Chunhua Jiang, Yaogai Hu, Ercha Aa, Wengeng Huang, Jing Liu, Guobin Yang, and Zhengyu Zhao. "Ionosonde Observations of Spread F and Spread Es at Low and Middle Latitudes during the Recovery Phase of the 7–9 September 2017 Geomagnetic Storm." Remote Sensing 13, no. 5 (March 7, 2021): 1010. http://dx.doi.org/10.3390/rs13051010.

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This study presents observations of nighttime spread F/ionospheric irregularities and spread Es at low and middle latitudes in the South East Asia longitude of China sectors during the recovery phase of the 7–9 September 2017 geomagnetic storm. In this study, multiple observations, including a chain of three ionosondes located about the longitude of 100°E, Swarm satellites, and Global Navigation Satellite System (GNSS) ROTI maps, were used to study the development process and evolution characteristics of the nighttime spread F/ionospheric irregularities at low and middle latitudes. Interestingly, spread F and intense spread Es were simultaneously observed by three ionosondes during the recovery phase. Moreover, associated ionospheric irregularities could be observed by Swarm satellites and ground-based GNSS ionospheric TEC. Nighttime spread F and spread Es at low and middle latitudes might be due to multiple off-vertical reflection echoes from the large-scale tilts in the bottom ionosphere. In addition, we found that the periods of the disturbance ionosphere are ~1 h at ZHY station, ~1.5 h at LSH station and ~1 h at PUR station, respectively. It suggested that the large-scale tilts in the bottom ionosphere might be produced by LSTIDs (Large scale Traveling Ionospheric Disturbances), which might be induced by the high-latitude energy inputs during the recovery phase of this storm. Furthermore, the associated ionospheric irregularities observed by satellites and ground-based GNSS receivers might be caused by the local electric field induced by LSTIDs.

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Wu, Bingyi. "Winter Atmospheric Circulation Anomaly Associated with Recent Arctic Winter Warm Anomalies." Journal of Climate 30, no. 21 (November 2017): 8469–79. http://dx.doi.org/10.1175/jcli-d-17-0175.1.

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The winter Arctic atmosphere in the middle and lower troposphere has shifted to a warmer stage since the winter of 2004/05 relative to the mean averaged from 1979/80 to 2003/04. Recent Arctic warm anomalies are concurrent with warm anomalies over the North Pacific, northern Africa, and the low latitudes of both the North American and Asian continents and with cold anomalies over the middle and high latitudes of Eurasia and North America. Meanwhile, strengthened winter SLP is observed in the middle and high latitudes of Eurasia, the Siberian marginal seas of the Arctic Ocean, and the North Pacific. Correspondingly, winter 500-hPa geopotential height anomalies exhibit wave train structures over Eurasia, the North Pacific, and North America. These major features frequently reappear since the winter of 2004/05. A regionally averaged winter SLP in 40°–65°N, 30°E–150°W can be regarded as the intensity index to characterize interannual variability of the atmospheric circulation anomaly associated with recent Arctic warm anomalies. This atmospheric circulation anomaly differs from the Arctic dipole anomaly and displays a closer association with atmospheric variability over the middle and low latitudes relative to the Arctic. It directly connects Arctic warm anomalies in the middle and lower troposphere to increased frequencies of extreme cold events in the middle and low latitudes of Eurasia and western North Pacific, and western North America. This study also implies that SST cooling in the tropical central and eastern Pacific may also contribute to recent Arctic warm anomalies, although its impact mechanism is not clear yet.

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Remsberg, E. "On the observed changes in upper stratospheric and mesospheric temperatures from UARS HALOE." Annales Geophysicae 26, no. 5 (May 28, 2008): 1287–97. http://dx.doi.org/10.5194/angeo-26-1287-2008.

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Abstract. Temperature versus pressure or T(p) time series from the Halogen Occultation Experiment (HALOE) of the Upper Atmosphere Research Satellite (UARS) have been extended and re-analyzed for the period of 1991–2005 and for the upper stratosphere and mesosphere in 10-degree wide latitude zones from 60 S to 60 N. Even though sampling from a solar occultation experiment is somewhat limited, it is shown to be quite adequate for developing both the seasonal and longer-term variations in T(p). Multiple linear regression (MLR) techniques were used in the re-analyses for the seasonal and the significant interannual, solar cycle (SC-like or decadal-scale), and linear trend terms. Plots of the amplitudes and phases for the interannual (QBO and subbiennial) terms are provided. A simple SC-like term of 11-yr period was fitted to the time series residuals after accounting for the seasonal and interannual terms. Highly significant SC-like responses were found for both the upper mesosphere and the upper stratosphere. The phases of these SC-like terms were checked for their continuity with latitude and pressure-altitude; the larger amplitude responses are directly in-phase with that of standard proxies for the solar flux variations. The analyzed, max minus min, responses at low latitudes are of order 0.5 to 1 K, while at middle latitudes they are as large as 3 K in the upper mesosphere. Highly significant, linear cooling trends were found at middle latitudes of the middle to upper mesosphere (−1.5 to −2.0 K/decade), at tropical latitudes of the lower mesosphere (about −0.5 K/decade), and at 2 hPa (of order −1 K/decade). Both the diagnosed solar cycle responses and trends from HALOE for the mid to upper mesosphere at middle latitudes are larger than simulated with most models, perhaps an indication of decadal-scale dynamical forcings that are not being simulated so well.

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Prölss, G. W. "Common origin of positive ionospheric storms at middle latitudes and the geomagnetic activity effect at low latitudes." Journal of Geophysical Research: Space Physics 98, A4 (April 1, 1993): 5981–91. http://dx.doi.org/10.1029/92ja02777.

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Xiong, Chao, Claudia Stolle, and Jaeheung Park. "Climatology of GPS signal loss observed by Swarm satellites." Annales Geophysicae 36, no. 2 (April 26, 2018): 679–93. http://dx.doi.org/10.5194/angeo-36-679-2018.

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Abstract. By using 3-year global positioning system (GPS) measurements from December 2013 to November 2016, we provide in this study a detailed survey on the climatology of the GPS signal loss of Swarm onboard receivers. Our results show that the GPS signal losses prefer to occur at both low latitudes between ±5 and ±20∘ magnetic latitude (MLAT) and high latitudes above 60∘ MLAT in both hemispheres. These events at all latitudes are observed mainly during equinoxes and December solstice months, while totally absent during June solstice months. At low latitudes the GPS signal losses are caused by the equatorial plasma irregularities shortly after sunset, and at high latitude they are also highly related to the large density gradients associated with ionospheric irregularities. Additionally, the high-latitude events are more often observed in the Southern Hemisphere, occurring mainly at the cusp region and along nightside auroral latitudes. The signal losses mainly happen for those GPS rays with elevation angles less than 20∘, and more commonly occur when the line of sight between GPS and Swarm satellites is aligned with the shell structure of plasma irregularities. Our results also confirm that the capability of the Swarm receiver has been improved after the bandwidth of the phase-locked loop (PLL) widened, but the updates cannot radically avoid the interruption in tracking GPS satellites caused by the ionospheric plasma irregularities. Additionally, after the PLL bandwidth increased larger than 0.5 Hz, some unexpected signal losses are observed even at middle latitudes, which are not related to the ionospheric plasma irregularities. Our results suggest that rather than 1.0 Hz, a PLL bandwidth of 0.5 Hz is a more suitable value for the Swarm receiver. Keywords. Ionosphere (equatorial ionosphere; ionospheric irregularities) – radio science (radio wave propagation)

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Flasar, F. M., and R. K. Achterberg. "The structure and dynamics of Titan's middle atmosphere." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 367, no. 1889 (November 21, 2008): 649–64. http://dx.doi.org/10.1098/rsta.2008.0242.

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Titan's middle atmosphere is characterized by cyclostrophic winds and strong seasonal modulation. Cassini CIRS observations, obtained in northern winter, indicate that the stratosphere near 1 mbar is warmest at low latitudes, with the South Pole a few degrees colder and the North Pole approximately 20 K colder. Associated with the cold northern temperatures are strong circumpolar winds with speeds as high as 190 m s −1 . Within this vortex, the mixing ratios of several organic gases are enhanced relative to those at low latitudes. Comparison with Voyager thermal infrared measurements, obtained 25 years ago in northern spring, suggests that the enhancement currently observed will increase as the winter progresses. The stratopause height increases from 0.1 mbar near the equator to 0.01 mbar near the North Pole, where it is the warmest part of the atmosphere, greater than 200 K. This implies subsidence at the pole, which is consistent with the enhanced organics observed. Condensate features, several still not identified, are also apparent in the infrared spectra at high northern latitudes. In many ways, the winter vortex observed on Titan, with cyclostrophic winds, resembles the polar winter vortices on the Earth, where the mean winds are geostrophic.

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Liu, J., B. Zhao, and L. Liu. "Time delay and duration of ionospheric total electron content responses to geomagnetic disturbances." Annales Geophysicae 28, no. 3 (March 18, 2010): 795–805. http://dx.doi.org/10.5194/angeo-28-795-2010.

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Abstract. Although positive and negative signatures of ionospheric storms have been reported many times, global characteristics such as the time of occurrence, time delay and duration as well as their relations to the intensity of the ionospheric storms have not received enough attention. The 10 years of global ionosphere maps (GIMs) of total electron content (TEC) retrieved at Jet Propulsion Laboratory (JPL) were used to conduct a statistical study of the time delay of the ionospheric responses to geomagnetic disturbances. Our results show that the time delays between geomagnetic disturbances and TEC responses depend on season, magnetic local time and magnetic latitude. In the summer hemisphere at mid- and high latitudes, the negative storm effects can propagate to the low latitudes at post-midnight to the morning sector with a time delay of 4–7 h. As the earth rotates to the sunlight, negative phase retreats to higher latitudes and starts to extend to the lower latitude toward midnight sector. In the winter hemisphere during the daytime and after sunset at mid- and low latitudes, the negative phase appearance time is delayed from 1–10 h depending on the local time, latitude and storm intensity compared to the same area in the summer hemisphere. The quick response of positive phase can be observed at the auroral area in the night-side of the winter hemisphere. At the low latitudes during the dawn-noon sector, the ionospheric negative phase responses quickly with time delays of 5–7 h in both equinoctial and solsticial months. Our results also manifest that there is a positive correlation between the intensity of geomagnetic disturbances and the time duration of both the positive phase and negative phase. The durations of both negative phase and positive phase have clear latitudinal, seasonal and magnetic local time (MLT) dependence. In the winter hemisphere, long durations for the positive phase are 8–11 h and 12–14 h during the daytime at middle and high latitudes for 20≤Ap<40 and Ap≥40.

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Spicer, Robert A., Jack A. Wolfe, and Douglas J. Nichols. "Alaskan Cretaceous-Tertiary floras and Arctic origins." Paleobiology 13, no. 1 (1987): 73–83. http://dx.doi.org/10.1017/s0094837300008599.

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Cretaceous floras in Alaska, when compared to those at mid-latitudes, generally indicate later appearances in Alaska of major clades and major leaf morphologies. Compared to mid-latitude floras, Alaskan Late Cretaceous floras contain few major clades. The Alaskan clades diversified but at a low taxonomic level. Migrational pathways into high latitudes were probably along streams. Similar patterns characterized the Alaskan Tertiary, although some southward migrations of lineages occurred during the Neogene.Review of other Arctic paleontological data from Ellesmere Island, previously used to suggest that the Arctic was a major center of origin during the Late Cretaceous, indicates that the ages of supposedly substantiating dinoflagellate floras were misinterpreted. When the dinoflagellate data are interpreted according to standard methodology, first occurrences of genera and species groups on Ellesmere are, like the Alaskan occurrences, later than first occurrences at middle latitudes.

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Třísková, L., V. Truhlík, and J. Šmilauer. "Empirical modeling of the upper transition height for low and middle latitudes." Advances in Space Research 27, no. 1 (January 2001): 111–14. http://dx.doi.org/10.1016/s0273-1177(00)00145-9.

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Li, Qi, Yufen Gao, Jianjun Wang, and De-Sheng Han. "Local differences in great magnetic storms observed at middle and low latitudes." Earth, Planets and Space 61, no. 8 (August 2009): 995–1001. http://dx.doi.org/10.1186/bf03352949.

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Ma, Ruiping, Jiyao Xu, Wenbin Wang, Jiuhou Lei, Han-Li Liu, Astrid Maute, and Maura E. Hagan. "Variations of the nighttime thermospheric mass density at low and middle latitudes." Journal of Geophysical Research: Space Physics 115, A12 (December 2010): n/a. http://dx.doi.org/10.1029/2010ja015784.

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Zhang, YanYan, LiBo Liu, YiDing Chen, Jing Liu, You Yu, and Ming Li. "Nighttime electron density enhancements at middle and low latitudes in East Asia." Science China Earth Sciences 58, no. 4 (January 20, 2015): 551–61. http://dx.doi.org/10.1007/s11430-014-4953-x.

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Mansilla, Gustavo A. "Moderate geomagnetic storms and their ionospheric effects at middle and low latitudes." Advances in Space Research 48, no. 3 (August 2011): 478–87. http://dx.doi.org/10.1016/j.asr.2011.03.034.

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Leblanc, Thierry, I. Stuart McDermid, Philippe Keckhut, Alain Hauchecorne, C. Y. She, and David A. Krueger. "Temperature climatology of the middle atmosphere from long-term lidar measurements at middle and low latitudes." Journal of Geophysical Research: Atmospheres 103, no. D14 (July 1, 1998): 17191–204. http://dx.doi.org/10.1029/98jd01347.

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Yang, Sheng Nan, Xiao Fu Huang, Mao Jun Zhong, and Wen Bo Liao. "Geographical variation in limb muscle mass of the Andrew’s toad (Bufo andrewsi)." Animal Biology 67, no. 1 (2017): 17–28. http://dx.doi.org/10.1163/15707563-00002518.

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Muscles are vital for the process of movement, mating and escape of predators in amphibians. During evolution, the morphological and genetic characteristics as well as the size of muscles in species will change to adapt different environments. Theory predicts that low male-male competition in high-altitude/latitude selects for small limb muscles. Here, we used the Andrew’s toad (Bufo andrewsi) as a model animal to test this prediction by analyzing geographical variation in the mass of limb muscles across nine populations from the Hengduan Mountains in China. Inconsistent with the prediction, we found that latitude and altitude did not affect the relative mass of total combined limb muscles and mass of combined hindlimb muscles among populations. Meanwhile, the relative mass of combined forelimb muscles, the two forelimb muscles (flexor carpi radialis and extensor carpi radialis) and the four hindlimb muscles (e.g. biceps femoris, semimebranous, semitendinosus and peroneus) was lowest in middle latitude and largest in low latitude whereas gracilis minor was largest in high latitudes. However, we did not find any correlations between the two forelimb muscles and the four hindlimb muscles and altitude. Our findings suggest that combined forelimb muscles, flexor carpi radialis, extensor carpi radialis, biceps femoris, semimebranous, semitendinosus and peroneus are largest in low latitudes due to pressures of mate competition.

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Pearce-Higgins, James W., Nancy Ockendon, David J. Baker, Jamie Carr, Elizabeth C. White, Rosamunde E. A. Almond, Tatsuya Amano, et al. "Geographical variation in species' population responses to changes in temperature and precipitation." Proceedings of the Royal Society B: Biological Sciences 282, no. 1818 (November 7, 2015): 20151561. http://dx.doi.org/10.1098/rspb.2015.1561.

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Despite increasing concerns about the vulnerability of species' populations to climate change, there has been little overall synthesis of how individual population responses to variation in climate differ between taxa, with trophic level or geographically. To address this, we extracted data from 132 long-term (greater than or equal to 20 years) studies of population responses to temperature and precipitation covering 236 animal and plant species across terrestrial and freshwater habitats. Our results identify likely geographical differences in the effects of climate change on populations and communities in line with macroecological theory. Temperature tended to have a greater overall impact on populations than precipitation, although the effects of increased precipitation varied strongly with latitude, being most positive at low latitudes. Population responses to increased temperature were generally positive, but did not vary significantly with latitude. Studies reporting significant climatic trends through time tended to show more negative effects of temperature and more positive effects of precipitation upon populations than other studies, indicating climate change has already impacted many populations. Most studies of climate change impacts on biodiversity have focused on temperature and are from middle to high northern latitudes. Our results suggest their findings may be less applicable to low latitudes.

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Black, Robert X., and Brent A. McDaniel. "Interannual Variability in the Southern Hemisphere Circulation Organized by Stratospheric Final Warming Events." Journal of the Atmospheric Sciences 64, no. 8 (August 2007): 2968–74. http://dx.doi.org/10.1175/jas3979.1.

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A composite observational analysis is presented demonstrating that austral stratospheric final warming (SFW) events provide a substantial organizing influence upon the large-scale atmospheric circulation in the Southern Hemisphere. In particular, the annual weakening of high-latitude westerlies in the upper troposphere and stratosphere is accelerated during SFW onset. This behavior is associated with a coherent annular circulation change with zonal wind decelerations (accelerations) at high (low) latitudes. The high-latitude stratospheric decelerations are induced by the anomalous wave driving of upward-propagating tropospheric waves. Longitudinally asymmetric circulation changes occur in the lower troposphere during SFW onset with regionally localized height increases (decreases) at subpolar (middle) latitudes. Importantly, the tropospheric and stratospheric circulation change patterns identified here are structurally distinct from the Southern Annular Mode. It is concluded that SFW events are linked to interannual atmospheric variability with potential bearing upon weather and climate prediction.

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Su, S. Y., R. T. Tsunoda, C. H. Liu, C. K. Chao, and J. M. Wu. "ROCSAT observations of topside ionospheric undulations and irregularities at low to middle latitudes." Journal of Geophysical Research: Space Physics 112, A11 (November 2007): n/a. http://dx.doi.org/10.1029/2007ja012371.

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Tsunomura, Satoru. "Erratum to: Characteristics of geomagnetic sudden commencement observed in middle and low latitudes." Earth, Planets and Space 51, no. 1 (January 1999): 71. http://dx.doi.org/10.1186/bf03352211.

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Gan, Quan, Shao Dong Zhang, and Fan Yi. "TIMED/SABER observations of lower mesospheric inversion layers at low and middle latitudes." Journal of Geophysical Research: Atmospheres 117, no. D7 (April 12, 2012): n/a. http://dx.doi.org/10.1029/2012jd017455.

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Rong, Piao, Christian von Savigny, Chunmin Zhang, Christoph G. Hoffmann, and Michael J. Schwartz. "Response of middle atmospheric temperature to the 27 d solar cycle: an analysis of 13 years of microwave limb sounder data." Atmospheric Chemistry and Physics 20, no. 3 (February 13, 2020): 1737–55. http://dx.doi.org/10.5194/acp-20-1737-2020.

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Abstract. This work focuses on studying the presence and characteristics of 27 d solar signatures in middle atmospheric temperature observed by the microwave limb sounder (MLS) on NASA's Aura spacecraft. The 27 d signatures in temperature are extracted using the superposed epoch analysis (SEA) technique. We use time-lagged linear regression (sensitivity analysis) and a Monte Carlo test method (significance test) to explore the dependence of the results on latitude and altitude, solar activity, and season, as well as on different parameters (e.g., smoothing filter, window width and epoch centers). Using different parameters does impact the results to a certain degree, but it does not affect the overall results. Analyzing the 13-year data set shows that highly significant 27 d solar signatures in middle atmospheric temperature are present at many altitudes and latitudes. A tendency to higher temperature sensitivity to solar forcing in the winter hemisphere compared to the summer hemisphere is found. In addition, the sensitivity of temperature to 27 d solar forcing tends to be larger at high latitudes than at low latitudes. For 11-year solar minimum conditions no statistically significant identification of a 27 d solar signature is possible at most altitudes and latitudes. Several results we obtained suggest that processes other than solar variability drive atmospheric temperature variability at periods around 27 d. Comparisons of the obtained sensitivity values with earlier experimental and model studies show good overall agreement.

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Upchurch, Garland R. "Cretaceous vegetational change: a biomal perspective." Paleontological Society Special Publications 6 (1992): 295. http://dx.doi.org/10.1017/s2475262200008558.

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The Cretaceous rise of flowering plants marked an important transition in the modernization of terrestrial ecosystems. Well documented is the diversification of angiosperm pollen during the mid-Cretaceous and the migration of angiosperms from low latitudes to middle and high latitudes during the Barremian to Cenomanian. Global compilations of “species” diversity indicate a rapid rise in angiosperm diversity during the Albian to Cenomanian. This rise parallels a decline in the species diversity of archaic pteridophytes and the gymnosperm orders Cycadales, Bennettitales, Ginkgoales, Czekanowskiales, and Caytoniales. Late Cretaceous floras show more gradual trends in species diversity than mid-Cretaceous floras.Megafloral reconstructions of vegetation and climate for North America and other continents indicate warm temperatures in coastal regions of middle to high latitudes. Cretaceous biomes, however, often cannot be compared closely with Recent biomes. During much of the Cretaceous, conifers and other gymnosperms shared dominance with angiosperms in tropical and subtropical vegetation, unlike the Recent. During the Late Cretaceous, tropical rainforest was areally restricted. The few known leaf megafloras from equatorial regions indicate subhumid, rather than rainforest, conditions. Desert and semi-desert were widespread at lower latitudes and are documented by the occurrence of evaporite minerals in China, Africa, Spain, Mexico, and South America. Mid-latitude vegetation consisted of open-canopy broadleaved and coniferous evergreen woodlands that existed under subhumid conditions and low seasonality. High-latitude vegetation of the Northern Hemisphere consisted of coniferous and broadleaved deciduous forest, rather than boreal forest and tundra. High-latitude vegetation from coastal regions of the Southern Hemisphere consisted of evergreen conifers and angiosperms. Rainforest conditions appear to have been largely restricted to polar latitudes.Data on relative abundance, though often incomplete, indicate that angiosperms became ecologically important in tropical to warm subtropical broadleaved evergreen forests and woodlands by the Cenomanian. However, their rise to dominance took longer in other biomes. Conifers formed an important component of many Late Cretaceous biomes, and the persistence of archaic gymnosperms was strongly influenced by climate. Deciduous Ginkgoales, Czekanowskiales, Bennettitales, and Caytoniales are rare to absent in Late Cretaceous megafloras from warm subtropical to tropical climates, but they persist in megafloras from cooler climates. Archaic conifers such as Frenelopsis occur in megafloras representing low-latitude desert and semi-desert, but they are generally absent in more humid assemblages. Within mid-latitude broadleaved and coniferous evergreen woodland from North America, conifers show evidence for co-dominance with angiosperms into the early Maastrichtian. However, this co-dominance appears to have ended by latest Maastrichtian, which implies that vegetational reorganization occurred during the last few million years of the Cretaceous in North America.

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Grafe, A., P. A. Bespalov, V. Y. Trakhtengerts, and A. G. Demekhov. "Afternoon mid-latitude current system and low-latitude geomagnetic field asymmetry during geomagnetic storms." Annales Geophysicae 15, no. 12 (December 31, 1997): 1537–47. http://dx.doi.org/10.1007/s00585-997-1537-5.

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Abstract. For four geomagnetic storms of middle intensity the relationship between the low-latitude magnetic field asymmetry using ASY indices and the intensity of the auroral eastward and westward electrojet was considered. It was asked whether there exists a connection between ASY and the eastward electrojet. To answer this question equivalent current systems were estimated in mid-latitudes. It was found that the observations obviously show no correlative relationship between the low-latitude magnetic-field asymmetry and the eastward electrojet, whereas one exists between ASY and the westward electrojet. To explain the generally accepted common three-dimensional current system between the partial ring current and the eastward electrojet, a condensor model of the three-dimensional current system was developed. It could be shown that the short periodic variations of the partial ring current are shielded by the condensor and cannot influence the eastward-electrojet current.

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Laskar, Fazlul I., Gunter Stober, Jens Fiedler, Meers M. Oppenheim, Jorge L. Chau, Duggirala Pallamraju, Nicholas M. Pedatella, Masaki Tsutsumi, and Toralf Renkwitz. "Mesospheric anomalous diffusion during noctilucent cloud scenarios." Atmospheric Chemistry and Physics 19, no. 7 (April 17, 2019): 5259–67. http://dx.doi.org/10.5194/acp-19-5259-2019.

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Abstract. The Andenes specular meteor radar shows meteor trail diffusion rates increasing on average by about 10 % at times and locations where a lidar observes noctilucent clouds (NLCs). This high-latitude effect has been attributed to the presence of charged NLC after exploring possible contributions from thermal tides. To make this claim, the current study evaluates data from three stations at high, middle, and low latitudes for the years 2012 to 2016 to show that NLC influence on the meteor trail diffusion is independent of thermal tides. The observations also show that the meteor trail diffusion enhancement during NLC cover exists only at high latitudes and near the peaks of NLC layers. This paper discusses a number of possible explanations for changes in the regions with NLCs and leans towards the hypothesis that the relative abundance of background electron density plays the leading role. A more accurate model of the meteor trail diffusion around NLC particles would help researchers determine mesospheric temperature and neutral density profiles from meteor radars at high latitudes.

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Manson, A. H., C. Meek, T. Chshyolkova, C. McLandress, S. K. Avery, D. C. Fritts, C. M. Hall, et al. "Winter warmings, tides and planetary waves: comparisions between CMAM (with interactive chemistry) and MFR-MetO observations and data." Annales Geophysicae 24, no. 10 (October 20, 2006): 2493–518. http://dx.doi.org/10.5194/angeo-24-2493-2006.

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Abstract. Following earlier comparisons using the Canadian Middle Atmosphere Model (CMAM, without interactive chemistry), the dynamical characteristics of the model are assessed with interactive chemistry activated. Time-sequences of temperatures and winds at Tromsø (70° N) show that the model has more frequent and earlier stratospheric winter warmings than typically observed. Wavelets at mesospheric heights (76, 85 km) and from equator to polar regions show that CMAM tides are generally larger, but planetary waves (PW) smaller, than medium frequency (MF) radar-derived values. Tides modelled for eight geographic locations during the four seasons are not strikingly different from the earlier CMAM experiment; although monthly data now allow these detailed seasonal variations (local combinations of migrating and non-migrating components) within the mesosphere (circa 50–80 km) to be demonstrated for the first time. The dominant semi-diurnal tide of middle latitudes is, as in the earlier papers, quite well realized in CMAM. Regarding the diurnal tide, it is shown here and in an earlier study by one of the authors, that the main characteristics of the diurnal tide at low latitudes (where the S (1,1) mode dominates) are well captured by the model. However, in this experiment there are some other unobserved features for the diurnal tide, which are quite similar to those noted in the earlier CMAM experiment: low latitude amplitudes are larger than observed at 82 km, and middle latitudes feature an unobserved low altitude (73 km) summer maximum. Phases, especially at low and middle (circa 42° N) latitudes, do not match observations well. Mesospheric seasonal tidal variations available from the CUJO (Canada U.S.\\ Japan Opportunity) radar (MFR) network (sites 40–45° N) reveal interesting longitudinal differences between the CMAM and the MFR observations. In addition, model and observations differ in the character of the vertical phase variations at each network-location. Finally, the seasonal variations of planetary wave (PW) activity available from CMAM and the MFR show quite good agreement, apart from the amplitude differences (smaller in CMAM above 70 km). A major difference for the 16-d PW is that CMAM shows large amplitudes before the winter solstice; and for the 2-d PW, while both CMAM and MFR show summer and winter activity, the observed summer mesopause and winter mesospheric wave activities are stronger and more extended in height. Models such as CMAM, operated without data-assimilation, are now able to provide increasingly realistic climatologies of middle atmosphere tides and PW activity. Differences do exist however, and so discussion of the various factors affecting tidal and PW characteristics in atmospheres, modelled and observed, is provided. Other diagnostics of model-characteristics and of future desirable model experiments are suggested.

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Kane, R. P. "Interannual variability of precipitable water." Annales Geophysicae 14, no. 4 (April 30, 1996): 464–67. http://dx.doi.org/10.1007/s00585-996-0464-1.

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Abstract. The 12-month running means of the surface-to-500 mb precipitable water obtained from analysis of radiosonde data at seven selected locations showed three types of variability viz: (1) quasi-biennial oscillations; these were different in nature at different latitudes and also different from the QBO of the stratospheric tropical zonal winds; (2) decadal effects; these were prominent at middle and high latitudes and (3) linear trends; these were prominent at low latitudes, up trends in the Northern Hemisphere and downtrends in the Southern Hemisphere.

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Bolaji, Olawale, Oluwafisayo Owolabi, Elijah Falayi, Emmanuel Jimoh, Afolabi Kotoye, Olumide Odeyemi, Babatunde Rabiu, et al. "Observations of equatorial ionization anomaly over Africa and Middle East during a year of deep minimum." Annales Geophysicae 35, no. 1 (January 20, 2017): 123–32. http://dx.doi.org/10.5194/angeo-35-123-2017.

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Abstract. In this work, we investigated the veracity of an ion continuity equation in controlling equatorial ionization anomaly (EIA) morphology using total electron content (TEC) of 22 GPS receivers and three ground-based magnetometers (Magnetic Data Acquisition System, MAGDAS) over Africa and the Middle East (Africa–Middle East) during the quietest periods. Apart from further confirmation of the roles of equatorial electrojet (EEJ) and integrated equatorial electrojet (IEEJ) in determining hemispheric extent of EIA crest over higher latitudes, we found some additional roles played by thermospheric meridional neutral wind. Interestingly, the simultaneous observations of EIA crests in both hemispheres of Africa–Middle East showed different morphology compared to that reported over Asia. We also observed interesting latitudinal twin EIA crests domiciled at the low latitudes of the Northern Hemisphere. Our results further showed that weak EEJ strength associated with counter electrojet (CEJ) during sunrise hours could also trigger twin EIA crests over higher latitudes.

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García-Comas, M., B. Funke, A. Gardini, M. López-Puertas, A. Jurado-Navarro, T. von Clarmann, G. Stiller, et al. "MIPAS temperature from the stratosphere to the lower thermosphere: comparison of version vM21 with ACE-FTS, MLS, OSIRIS, SABER, SOFIE and lidar measurements." Atmospheric Measurement Techniques Discussions 7, no. 7 (July 4, 2014): 6651–97. http://dx.doi.org/10.5194/amtd-7-6651-2014.

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Abstract. We present vM21 MIPAS temperatures from the lower stratosphere to the lower thermosphere, which cover all optimized resolution measurements performed by MIPAS in the Middle Atmosphere, Upper Atmosphere and NoctiLucent Cloud modes during its lifetime. i.e., from January 2005 to March 2012. The main upgrades with respect to the previous version of MIPAS temperatures (vM11) are the update of the spectroscopic database, the use of a different climatology of atomic oxygen and carbon dioxide, and the improvement of important technical aspects of the retrieval setup (temperature gradient along the line of sight and offset regularizations, apodization accuracy). Additionally, an updated version of ESA calibrated L1b spectra (5.02/5.06) is used. The vM21 temperatures correct the main systematic errors of the previous version because they on average provide a 1–2 K warmer stratopause and middle mesosphere, and a 6–10 K colder mesopause (except in high latitude summers) and lower thermosphere. These lead to a remarkable improvement of MIPAS comparisons with ACE-FTS, MLS, OSIRIS, SABER, SOFIE and the two Rayleigh lidars at Mauna Loa and Table Mountain, that, with few specific exceptions, typically exhibit differences smaller than 1 K below 50 km and than 2 K at 50–80 km in spring, autumn, winter at all latitudes, and summer at low to mid-latitudes. Differences in the high latitude summers are typically smaller than 1 K below 50 km, smaller than 2 K at 50–65 km and 5 K at 65–80 km. Differences with the other instruments in the mid-mesosphere are generally negative. MIPAS mesopause is within 4 K of the other instruments measurements, except in the high latitude summers, where it is within 5–10 K of the other instruments, being warmer than SABER, MLS and OSIRIS and colder than ACE-FTS and SOFIE. The agreement in the lower thermosphere is typically better than 5 K, except for high latitudes during spring and summer, where MIPAS usually exhibits larger vertical gradients.

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Hao Shu-Ji, Zhang Wen-Chao, Zhang Ya-Bin, Yang Ju-Tao, and Ma Guang-Lin. "Modeling of radio wave propagations under sporadic-E influence at low and middle latitudes." Acta Physica Sinica 66, no. 11 (2017): 119401. http://dx.doi.org/10.7498/aps.66.119401.

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Journal articles on the topic 'Middle and low latitudes'

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