Global structure,seasonal and interannual variability of the eastward propagating tides seen in the SABER/TIMED temperatures (2002–2007)

The present paper is focused on the global spatial (altitude and latitude) structure, seasonal and interannual variability of the most stable in amplitude and phase eastward propagating diurnal and semidiurnal tides with zonal wavenumbers 2 and 3 derived from the SABER/TIMED temperatures for full 6 years (January 2002–December 2007). The tidal results are obtained by an analysis method where the tides (migrating and nonmigrating) and the planetary waves (zonally travelling, zonally symmetric and stationary) are simultaneously extracted from the satellite data. It has been found that the structures of the eastward propagating diurnal tides with zonal wavenumbers 3 and 2 change from antisymmetric with respect to the equator below ∼85 km height, to more symmetric above ∼95 km. The seasonal behavior of the DE3 is dominated by annual variation with maximum in August–September reaching average (2002–2007) amplitude of ∼15 K, while that of the DE2 by semiannual variation with solstice maxima and with average amplitude of ∼8 K. These tides revealed some interannual variability with a period of quasi-2 years. The seasonal behavior of the eastward propagating semidiurnal tide with zonal wavenumber 2 in the southern hemisphere (SH) is dominated by annual variation with maximum in the austral summer (November–January) while that in the northern hemisphere (NH) by semiannual variation with equinoctial maxima. The SE2 maximizes near 115 km height and at latitude of ∼30° reaching an average amplitude of ∼6 K. The seasonal behavior of the eastward propagating semidiurnal tide with zonal wavenumber 3 in both hemispheres indicates a main maximum during June solstice and a secondary one during December solstice. The tide maximizes near 110–115 km height and at a latitude of ∼30° reaching an average amplitude of ∼4.8 K in the SH and ∼4 K in the NH. The tidal structures of the two eastward propagating semidiurnal tides are predominantly antisymmetric about the equator.     

Structure of the migrating diurnal tide in the Whole Atmosphere Community Climate Model (WACCM)

As part of an ongoing effort to understand the migrating diurnal tide generated by the NCAR Whole Atmosphere Community Climate Model, version 3 (WACCM3), we compare the WACCM3 migrating diurnal tide in the horizontal wind and temperature fields to similar results from the Global Scale Wave Model (GSWM). The WACCM3 diurnal tidal wind fields are also compared to tropical radar measurements at Kauai (22°N, 200.2°E) and Rarotonga (21.3°S, 199.7°E). The large-scale features of the WACCM3 results, such as the global spatial structure and the semiannual amplitude variation are in general agreement with past tidal studies; however, several differences do exist. WACCM3 exhibits a much higher degree of hemispheric asymmetry, lower overall amplitudes around the equinoxes, and peaks which are more confined in latitude when compared with the GSWM. Factors which may contribute to such differences between WACCM3 and GSWM are the solar heating profiles from ozone and water vapor, dissipation, and the zonal mean zonal winds. We find that the internally generated heating in WACCM3 and eddy dissipation values are both smaller than the values specified in the GSWM; the eddy dissipation fields and zonal mean zonal winds of the two models also display measurable differences in spatial structure. Comparisons with radar data show several differences in spatial and seasonal structure. In particular, the diurnal tide zonal winds in WACCM3 above Kauai are considerably larger in amplitude than those observed in the radar data, due to contributions from nonmigrating tidal components including wave numbers eastward 1 through 3, westward 2, and stationary components, which interfere constructively with the migrating component around equinox in WACCM3.     

XMM-Newton observations of the Mouse,SLX 1744–299 and SLX 1744–300

We observed the radio and X-ray source G359.23–0.82, also known as “the Mouse”, with XMM-Newton. The X-ray image of this object shows a point-like source at the Mouse’s “head”, accompanied by a “tail” that extends for about 40″ westward. The morphology is consistent with that observed recently with Chandra [Gaensler, B.M., van der Swaluw, E., Camilo, F., et al. The Mouse that soared: high resolution X-ray imaging of the pulsar-powered bow shock G359.23–0.82, ApJ 616, 383–402, 2004]. The spectrum of the head can be described by a power-law model with a photon index Γ ≃ 1.9. These results confirm that the Mouse is a bow-shock pulsar wind nebula (PWN) powered by PSR J1747–2958. We found that the hydrogen column density toward the Mouse, N_H = (2.60 ± 0.09) × 10²² cm⁻², is 20%–40% lower than those toward two serendipitously detected X-ray bursters, SLX 1744–299 and SLX 1744–300. At a plausible distance of 5 kpc, the X-ray luminosity of the Mouse, L(0.5–10 keV) = 3.7 × 10³⁴ erg s⁻¹, is 1.5% of the pulsar’s spin-down luminosity. We detected a Type I X-ray burst from SLX 1744–300 and found a possible decrease of N_H and persistent luminosity for this source, in comparison with those observed with ROSAT in 1992.     

Investigation on the MLT tidal variability during September 2019 minor sudden stratospheric warming

Tidal variability in the mesosphere and lower thermosphere (MLT) during September 2019 Southern hemisphere minor sudden stratospheric warming (SSW) is investigated utilizing ground-based meteor radar wind observations from the equatorial, extratropical, middle, and high latitude stations and global reanalysis dataset. The polar warming is found to move from the mesosphere to the stratosphere until the peak warming day (PWD) of the SSW. The diurnal and semidiurnal tides at individual observational sites do not exhibit any consistent response during the observational interval, but a notable and consistent variability in some specific zonal wavenumber components, i. e., DW1 (migrating diurnal tide), DE3 (nonmigrating eastward wavenumber 3 diurnal tide), and SW2 (migrating semidiurnal tide) is found in the global reanalysis dataset. Incidentally, the warming event occurs during Spring equinox when a dominant seasonal change in the tidal activities generally takes place and hence seasonal variability is also looked into while identifying the SSW impact during the observational interval. It is found that the seasonal broad changes in the DW1, DE3, and SW2 amplitudes can be explained by the variability in the tidal sources, i.e., water vapor, convective activity, ozone, etc during the observational period. However, the extracted short-term variability in the global tidal modes on removing seasonal trend reveals noticeable response in connection with the warming event. The deseasoned amplitude of the DW1 significantly enhances around the PWD at most of the present latitudes. The deseasoned DE3 amplitude responds significantly in the middle atmosphere at low latitudes during the warming phase. The deseasoned SW2 exhibit clear enhancement around the PWD at all the latitudes. However, the deseasoned tidal features do not seem to correlate well with that of the source species unlike the seasonal ones that imply involvement of complex processes during the warming event, seeking further future investigations in this regard.     

Hard X-ray footpoint motions in solar flares: Comparing magnetic reconnection models with observations

Hard X-ray observations from the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) of the October 29, 2003 GOES X10 two-ribbon flare are used together with magnetic field observations from the Michelson Doppler Imager (MDI) onboard SoHO to compare footpoint motions with predictions from magnetic reconnection models. The temporal variations of the velocity v of the hard X-ray footpoint motions and the photospheric magnetic field strength B in footpoints are investigated. The underlying photospheric magnetic field strength is generally higher (B ∼ 700–1200 G) in the slower moving (v ∼ 20–50 km s⁻¹) western footpoint than in the faster (v ∼ 20–100 km s⁻¹) moving eastern source (∼100–600 G). Furthermore, a rough temporal correlation between the HXR flux and the product vB² is observed.     

A Gemini observation of the anomalous X-ray pulsar 1RXS J170849-400910

The anomalous X-ray pulsars (AXPs) represent a growing class of neutron stars discovered at X-ray energies. While the nature of their multi-wavelength emission mechanism is still under debate, evidence has been recently accumulating in favor of their magnetar nature. Their study in the optical and infrared (IR) wavelengths has recently opened a new window to constrain the proposed models. We here present a brief overview of AXPs and our Gemini-South observation of 1RXS J170849-400910, which is a relatively bright AXP discovered with ROSAT and later found to be an 11 s X-ray pulsar by ASCA. The observation was taken with the near-IR imager Flamingos in J (1.25 μm), H (1.65 μm), and K_s (2.15 μm). We confirm the recent detection by (ApJ, 589, L93–L96) of a source coincident with the CHANDRA source (candidate ‘A’). Our derived magnitudes of J = 20.6 (0.2), H = 18.6 (0.2), and K_s = 17.1 (0.2) are consistent with those derived by (ApJ, 589, L93–L96), and indicate that if this source is indeed the IR counterpart to 1RXS J170849-400910, then there is no evidence of variability from this AXP. However, given the lack of IR variability and the relatively high IR to X-ray flux of this source when compared to the other AXPs, we conclude that this source is unlikely the counterpart of the AXP, and that the other source (candidate ‘B’) within the CHANDRA error circle should not be ruled out as the counterpart. Further monitoring of these sources and a deep observation of this complex field are needed to confirm the nature of these sources and their association with the AXP.     

大气中层顶区域波相互作用的一个观测个例

利用SOUSY VHF雷达的观测数据分析了极区中层顶83.4-91.2km范围内大气风场波动的非线性相互作用。大气风场的谱在不同高度上均有明显的潮汐分量峰值，纬向风分量中35h波、半日潮和8.9h惯必重力波构成共振相互作用对，经向风分量中33h波、半日潮和19h惯性重力波构成共振相互作用对。双谱分析表明，这些共振对在许多高度上都发生耦合，35h或33h波振幅的极小值与半日潮的极大值出现的高度几乎相同，呈现出明显的非线性相互作用在空间上不是局域的，而是存在于中层顶区域的几乎所有高度上，这种相互作用不仅导致半日潮振幅随时间的变化，也使半日潮的振幅随空间变化。35h和33h波动可能是在其他时段或其他位置通过行星波与周日潮相互作用产生的，然后传播到观测点并与半日潮发生相互作用。     

Scaling and universality of the thermal conductivity of liquid 4He near the superfluid transition and in restricted geometries

We present measurements of the thermal conductivity λ(t, P, L) = l/ρ(t, P, L) near the superfluid transition of ⁴He at saturated vapor pressure and confined in cylindrical geometries with radii L = 0.5 and 1.0 μm (t ≡ T/T_λ(P) − 1). For L = 1.0 μm measurements at six pressures P are presented. At and above T_λ the data are consistent with a universal scaling function F(X) = (L/ξ_o)^x/ν(ρ/ρ₀), X = (L/ξ_o)^1/νt valid for all P (ρ₀ and x are the pressure-dependent amplitude and effective exponent of the bulk resistivity ρ(t, P, ∞) = ρ₀t^x and ξ = ξ₀t^−ν is the correlation length). Indications of breakdown of scaling and universality are observed below T_λ.     

Gamma-ray observations of explosive nucleosynthesis products

In this review I discuss the various γ-ray emission lines that can be expected and, in some cases have been observed, from radioactive explosive nucleosynthesis products. The most important γ-ray lines result from the decay chains of ⁵⁶Ni, ⁵⁷Ni, and ⁴⁴Ti. ⁵⁶Ni is the prime explosive nucleosynthesis product of Type Ia supernovae, and its decay determines to a large extent the Type Ia light curves. ⁵⁶Ni is also a product of core-collapse supernovae, and in fact, γ-ray line emission from its daughter product, ⁵⁶Co, has been detected from SN1987A by several instruments. The early occurrence of this emission was surprising and indicates that some fraction of ⁵⁶Ni, which is synthesized in the innermost supernova layers, must have mixed with the outermost supernova ejecta.Special attention is given to the γ-ray line emission of the decay chain of ⁴⁴Ti (⁴⁴Ti → ⁴⁴Sc → ⁴⁴Ca), which is accompanied by line emission at 68, 78, and 1157 keV. As the decay time of ⁴⁴Ti is ∼86 yr, one expects this line emission from young supernova remnants. Although the ⁴⁴Ti yield (typically 10⁻⁵–10⁻⁴M_⊙) is not very high, its production is very sensitive to the energetics and asymmetries of the supernova explosion, and to the mass cut, which defines the mass of the stellar remnant. This makes ⁴⁴Ti an ideal tool to study the inner layers of the supernova explosion. This is of particular interest in light of observational evidence for asymmetric supernova explosions.The γ-ray line emission from ⁴⁴Ti has so far only been detected from the supernova remnant Cas A. I discuss these detections, which were made by COMPTEL (the 1157 keV line) and BeppoSAX (the 68 and 78 keV lines), which, combined, give a flux of (2.6 ± 0.4 ± 0.5) × 10⁻⁵ ph cm⁻² s⁻¹ per line, suggesting a ⁴⁴Ti yield of (1.5 ± 1.0) × 10⁻⁴M_⊙. Moreover, I present some preliminary results of Cas A observations by INTEGRAL, which so far has yielded a 3σ detection of the 68 keV line with the ISGRI instrument with a flux that is consistent with the BeppoSAX detections. Future observations by INTEGRAL-ISGRI will be able to constrain the continuum flux above 90 keV, as the uncertainty about the continuum shape, is the main source of systematic error for the 68 and 78 keV line flux measurements. Moreover, with the INTEGRAL-SPI instrument it will be possible to measure or constrain the line broadening of the 1157 keV line. A preliminary analysis of the available data indicates that narrow line emission (i.e., Δv < 1000 km s⁻¹) can be almost excluded at the 2σ level, for an assumed line flux of 1.9 × 10⁻⁵ ph cm⁻² s⁻¹.     

Supernova remnant 1987A: The latest report from the Chandra X-ray Observatory

We continue monitoring supernova remnant (SNR) 1987A with the Chandra X-ray Observatory. As of 2004 January, bright X-ray spots in the northwest and the southwest are now evident in addition to the bright eastern ring. The overall X-ray spectrum, since 2002 December, can be described by a planar shock with an electron temperature of ∼2.1 keV. The soft X-ray flux is now 8 × 10⁻¹³ ergs cm⁻² s⁻¹, which is about five times higher than four years ago. This flux increase rate is consistent with our prediction based on an exponential density distribution along the radius of the SNR between the HII region and the inner ring. We still have no direct evidence of a central point source, and place an upper limit of L_X = 1.3 × 10³⁴ ergs s⁻¹ on the 3–10 keV band X-ray luminosity.     

Coordinated lidar and TIMED observations of the quasi-two-day wave during August 2002–2004 and possible quasi-biennial oscillation influence

The Colorado State University sodium lidar, located in Fort Collins, CO (41N, 105W), is capable of both daytime and nighttime operations and has conducted a number of continuous multiple-day observational campaigns over the past few years. Three such campaigns, lasting between 80 and 90 h, were conducted during August 2002–2004 when mesospheric winds and temperature observations were collected simultaneously. These data were processed to extract the vertical structure and temporal evolution of the quasi-two-day wave, which was found to be significant in the power spectra. The quasi-two-day wave in temperature, zonal wind and meridional wind was analyzed for each year, indicating that the wave activity in 2003 was weaker than the other two years. Concurrent TIMED/SABER (2002–2004) and TIMED/TIDI observations (2004) in August were also processed. The SABER temperature shows a quasi-two-day wave with a dominant westward propagating zonal wavenumber four (s = −4) component in 2002 and 2004 but not in 2003. Analysis of the TIDI winds in August 2004 also indicates significant quasi-two-day wave activity, with the zonal wavenumber three and four components of comparable strength. The results of this coordinated ground-based lidar and TIMED satellite observations during August are presented. The possible influence of quasi-biennial oscillation on the inter-annual variability of the quasi-two-day wave is investigated.     

武汉上空中层和低热层大气潮汐的流星雷达观测

武汉流星雷达是2002年元月建成的我国第一部全天空流星雷达，本文对2002年2月19日到7月31日流星雷达观测的潮汐的讨论表明，武汉中层顶以周日潮汐为潮汐运动的主要分量，它的强度远大于半日潮汐，周日潮汐和半日潮汐的波源都在80km以下．周日潮汐分量在3、4月份最强，并且经向分量略强于纬向分量．两个分量的峰值在约95km处出现，分别达到44m／s和60m／s．半日潮的最大值24m／s出现在4月初约93km处．周日潮汐和半日潮汐的振幅和相位随时间呈现出拟周期变化的特征，这可能是潮汐与行星波非线形相互作用的结果．观测结果与GSWM模型的比较表明，GSWM模型在相位随高度变化趋势上与观测结果一致，但模型的周日潮相位比观测约超前1—2h，半日潮相位约滞后1—4h．在周日潮汐较强的月份，模型与观测有较大的差异，观测的幅度通常在95km附近有极大值，而模型并没有极大值．GSWM模型对半日潮的幅度的估计通常过小，观测的半日潮汐幅度有时甚至超过模型值的一倍以上．     

A spectroscopic measurement of high velocity spray plasma from an M-class flare and coronal mass ejection

The M1.5-class flare and associated coronal mass ejection (CME) of 16 February 2011 was observed with the Extreme ultraviolet Imaging Spectrometer on board the Hinode spacecraft. Spray plasma associated with the CME is found to exhibit a Doppler blue-shift of 850 km s^?1 – one of the largest values reported from spectroscopy of the solar disk and inner corona. The observation is unusual in that the emission line (Fe xii 193.51 Å) is not observed directly, but the Doppler shift is so large that the blue-shifted component appears in a wavelength window at 192.82 Å, intended to observe lines of O v, Fe xi and Ca xvii. The Fe xii 195.12 Å emission line is used as a proxy for the rest component of 193.51 Å. The observation highlights the risks of using narrow wavelength windows for spectrometer observations when observing highly-dynamic solar phenomena. The consequences of large Doppler shifts for ultraviolet solar spectrometers, including the upcoming Multi-slit Solar Explorer (MUSE) mission, are discussed.     

The temperature map of the loop and coronal sources of an occulted solar flare

An occulted solar flare occurred at about 06:07 UT on 2002, November 2. The RHESSI X-ray images show two separate parts. The lower part consists of a complete loop and the upper part a coronal source which well extends above the solar limb. The loop source shrank for about 3 min with a speed of ∼24 km s⁻¹ during the early impulsive phase and then expanded at ∼7 km s⁻¹, while the coronal source presented an upward motion at about 6 km s⁻¹. We obtained the temperature map of the loop source from RHESSI image spectrum. The temperature of the loop increases with altitude, indicating that the reconnection X-point of this flare is located above the loop source. However, the apparent coronal source is the top of another independent large-scale loop.     

The spatial distribution of galactic and anomalous cosmic rays in the heliosphere at solar minimum

The spatial distributions of galactic and anomalous cosmic rays in the heliosphere at the solar minima of Cycles 20/22 (qA > 0) and of Cycle 21 (qA < 0) are studied, using data from IMP 8, Voyagers 1/2 and Pioneer 10. It is found that the radial dependences of intensities J can be approximated by a power of radial distance r as J ∝ r^α with a different value of a constant in the inner and outer heliosphere with a transition at a radial distance of 10–15 AU. To study the physical meaning of these radial intensity profiles we examined the rigidity dependences of the intensity gradients by determining the particle mean free paths, using a simple one-dimensional modulation model. The particle mean free path λ was assumed to be a separable function of distance of the form r^γ and rigidity R of R^δ over the range of 0.5–3.0 GV in the inner and outer heliosphere. It was shown that λ of rigidity dependence of R^1.6 determined for Cycle 20/22 (qA > 0) with anomalous He is about 4–5 times larger than that of Cycle 21 (qA < 0) with R^0.9 at around 1 GV in the outer heliosphere, and that the radial dependences are r^1.4 and r^1.1, respectively, for Cycles 20/22 and for Cycle 21.     

Modeling the effects of pitch-angle scattering processes on the transport of solar energetic particles along the interplanetary magnetic field

We present a Monte-Carlo technique to study the time-dependent transport of energetic particles in the interplanetary medium. We use the guiding center approximation between discrete finite pitch-angle scatterings to quantify the competing effects of focusing and pitch-angle scattering on energetic particles propagating along a Parker spiral magnetic field. We consider that the pitch-angle scattering process is produced by small-scale magnetic field irregularities frozen in the expanding solar wind. We also include the effects of both solar wind convection and adiabatic deceleration. We use a joint probability distribution P(h, μ′) = p(h; μ′)q(μ′; μ) to describe both the distance traveled by the particle between two scattering processes and the change in the particle pitch-angle after a scattering process. Here, p(h; μ′) is the conditional probability that the particle travels a distance h along the field line before the next scattering if it had a pitch-angle cosine μ′ after the previous scattering, and q(μ′; μ) is the conditional probability for the pitch-angle cosine μ′ if the pitch-angle cosine was μ before the scattering. We consider several functional forms to describe the processes of pitch-angle scattering, such as an isotropic scattering without any memory of the initial particle’s pitch-angle or processes in which the scattering result depends upon the initial particle’s pitch-angle. The results of our simulations are pitch-angle distributions and time-intensity profiles that can be directly compared to spacecraft observations. Comparison of our simulations with near-relativistic (45–290 keV) electron events observed by the Electron, Proton and Alpha Monitor on board the Advanced Composition Explorer allows us to estimate both the time dependence of the injection of near-relativistic electrons into the interplanetary medium and the conditions for electron propagation along the interplanetary magnetic field.     

Centre-to-limb variation of photospheric facular radiance and image resolution

We study the effect of the angular resolution on the determination of the angular properties of the facular radiance. We analyze photospheric intensity in the continuum, around the Ni 676.8 nm line, and longitudinal magnetic field along the line of sight, measured by the MDI instrument aboard SOHO with two spatial resolutions, 4″ and 1.2″ (2″ and 0.6″ pixels, respectively). The effect of the limited photometric sensitivity of the instrument and the limited information on the angular structure of the magnetic field tubes are considered. Our study of the high-resolution data shows that intensity contrast of magnetic features between 80 and 600 Gauss increases from centre to limb up to a maximum that occurs at higher heliocentric angles (θ) when obtained with higher resolution data than for lower resolution data. There is a suggestion that at heliocentric angles below about 75° there is only a monotonic increase in the contrast as one goes from cos (θ) = 1 to cos (θ) = 0.2.     

Spectral filter for signal identification in the kHz SLR measurements of the fast spinning satellite Ajisai

The high repetition rate satellite laser ranging (SLR) measurements to the fast spinning satellites contain a frequency signal caused by the rotational motion of the corner cube reflector (CCR) array. The spectral filter, developed here, is based on the Lomb algorithm, and is tested with the simulated and the observed high repetition rate SLR data of the geodetic satellite Ajisai (spin period ∼2 s). The filter allows for the noise elimination from the SLR data, and for identification of the returns from the single CCRs of the array – even for the low return rates. Applying the spectral filter to the simulated SLR data increases the S/N ratio by a factor 40–45% for all return rates. Filtering out the noise from the observed data strengthens the frequency signal by factor of ∼25 for the low return rates, which significantly helps to determine the spin phase of the satellite. The spectral filter is applied to the Graz SLR data and the spin rates of Ajisai are determined by two different methods: the frequency analysis and the phase determination of the spinning retroreflector array.The analysis of more than 8 years of the Graz SLR measurements indicates an exponential spin rate trend: f = 0.67034 exp(−0.0148542 Y) [Hz], RMS = 0.085 mHz, where Y is the year since launch. The highly accurate spin rate information demonstrates periodic changes related to the precession of the orbital plane of Ajisai, as it determines the amount of energy received by the satellite from the Sun. The rate of deceleration of Ajisai is not constant: the half life period of the satellite’s spin oscillates around 46.7 years with an amplitude of about 5 years.     

The 16-day waves in the mesosphere and lower thermosphere over Wuhan (30.6°N, 114.5°E) and Adelaide (35°S, 138°E)

Winds from a meteor radar at Wuhan (30.6°N, 114.5°E) and a MF radar at Adelaide (35°S, 138°E) are used to study the 16-day waves in the mesosphere and lower thermosphere (MLT). The height range is 78–98 km at Wuhan and 70–98 km at Adelaide. By comparison, it is found that the zonal components at both sites are generally larger than the meridional ones, and eastward motion of the zonal background winds is favorable for the 16-day waves penetration to the MLT region. The zonal maximum amplitude appears in the autumn (September–October) around 86–98 km at Wuhan and in the winter months and early spring (July–October) around 72–82 km at Adelaide. Differences are found in wave amplitudes and time of appearance between the two years of 2002 and 2003. In 2003, the intensity of the wave amplitudes is relatively smaller than that for 2002 at both sites. The summer 16-day waves are comparatively weaker at Adelaide in both years, but stronger in 2002 at Wuhan near the mesopause and the lower thermosphere (86–98 km). The strong summer waves at Wuhan may come from the winter southern hemisphere.     

The total ozone and UV solar radiation over Stara Zagora,Bulgaria

The results from direct ground-based solar UV irradiance measurements and the total ozone content (TOC) over Stara Zagora (42° 25′N, 25° 37′E), Bulgaria are presented. During the period 1999–2003 the TOC data show seasonal variations, typical for the middle latitudes – maximum in the spring and minimum in the autumn. The comparison between TOC ground-based data and Global Ozone Monitoring Experiment (GOME) satellite-borne ones shows a seasonal dependence of the differences between them.A strong negative relationship between the total ozone and the 305 nm wavelength irradiance was found. The dependence between the two variables is significant (r = −0.62 ± 0.18) at 98% confidence level.The direct sun UV doses for some specific biological effects (erythema and eyes) are obtained. The estimation of the radiation amplification factor RAF shows that the ozone reduction by 1% increases the erythemal dose by 2.3%. The eye-damaging doses are more influenced by the TOC changes and in this case RAF = −2.7%.The amount of these biological doses depended on the solar altitude over the horizon. This dependence was not so strong when the total ozone content in the atmosphere was lower.