Wavelength Dependence of Solar Rotation and Solar Cycle UV Irradiance Variations

It is shown that for the 5-year period 1982 to 1987 the solar irradiance decrease is estimated to be about 5 to 7 percent over the spectral interval 195 to 225 nm. This change becomes progressively smaller with increasing wavelength. For the 2-1/3 year period, January 1987 to April 1989, the irradiance increases about 6 percent at 195 to 205 nm and about 2 percent between 215 to 250 nm. Both 27-day and 13.5-day relative amplitudes peak at the time near solar maximum (1982) but remain comparatively small between 1983 and the onset of solar cycle 22. An average 280 day oscillation is noted for wavelengths up to 230 nm. No physical mechanism is offered for this variation

Small-scale structures and the density irregularity of the inner corona

The observational evidence is considered that the electron density irregularity factor is much greater than unity in the inner corona, in particular, evidence derived from the photometric comparison of the K-corona emission p Beta with the EUV emission from coronal ions. A simple mathematical model was developed for the irregularity having a minimum number of parameters. This model was used to explore some implications of the observations and to show that well-known resolved structures such as polar plumes and coronal loops as presently understood cannot alone explain the irregularity

The solar spectral irradiance 1200-3184 a near solar maximum, 15 July 1980

Full disk solar spectral irradiances near solar maximum were obtained in the spectral range 1200 to 3184 A at a spectral resolution of approximately 1 A from rocket observations above White Sands Missile Range. Comparison with measurements made during solar minimum confirm a large increase at solar maximum in the solar irradiance near 1200 A with no change within the measurement errors near 2000 A. Irradiances in the range 1900 to 2100 A are in excellent agreement with previous measurements, and those in the 2100 to 2500 A range are lower than separate previous results in this range. Agreement is found with previous values 2500 to 2900 A A, and then fall below those values 2900 to 3184 A

Observed solar near UV variability: A contribution to variations of the solar constant

Continuous Measurements of the Solar UV have been made by an instrument on the Solar Mesosphere Explorer (SME) since October 1981. The results for the wavelength interval 200 to 300 nm show an irradiance decrease to a minimum in early 1987 and a subsequent increase to mid-April 1989. The observed UV changes during part of solar cycles 21 to 22 represent approx. 35 percent (during the decreasing phase) and 25 percent (during the increasing phase) of the observed variations of the solar constant for the same time period as the SME measurements

Modeling Solar Lyman Alpha Irradiance

Solar Lyman alpha irradiance is estimated from various solar indices using linear regression analyses. Models developed with multiple linear regression analysis, including daily values and 81-day running means of solar indices, predict reasonably well both the short- and long-term variations observed in Lyman alpha. It is shown that the full disk equivalent width of the He line at 1083 nm offers the best proxy for Lyman alpha, and that the total irradiance corrected for sunspot effect also has a high correlation with Lyman alpha

Facet ridge end points in crystal shapes

Equilibrium crystal shapes (ECS) near facet ridge end points (FRE) are generically complex. We study the body-centered solid-on-solid model on a square lattice with an enhanced uniaxial interaction range to test the stability of the so-called stochastic FRE point where the model maps exactly onto one dimensional Kardar-Parisi-Zhang type growth and the local ECS is simple. The latter is unstable. The generic ECS contains first-order ridges extending into the rounded part of the ECS, where two rough orientations coexist and first-order faceted to rough boundaries terminating in Pokrovsky-Talapov type end points.Comment: Contains 4 pages, 5 eps figures. Uses RevTe

Spacecraft instrument calibration and stability

The following topics are covered: instrument degradation; the Solar Backscatter Ultraviolet (SBUV) Experiment; the Total Ozone Mapping Spectrometer (TOMS); the Stratospheric Aerosol and Gas Experiment 1 (SAGE-1) and SAGE-2 instruments; the Solar Mesosphere Explorer (SME) UV ozone and near infrared airglow instruments; and the Limb Infrared Monitor of the Stratosphere (LIMS)

Temperature Dependence of Facet Ridges in Crystal Surfaces

The equilibrium crystal shape of a body-centered solid-on-solid (BCSOS) model on a honeycomb lattice is studied numerically. We focus on the facet ridge endpoints (FRE). These points are equivalent to one dimensional KPZ-type growth in the exactly soluble square lattice BCSOS model. In our more general context the transfer matrix is not stochastic at the FRE points, and a more complex structure develops. We observe ridge lines sticking into the rough phase where thesurface orientation jumps inside the rounded part of the crystal. Moreover, the rough-to-faceted edges become first-order with a jump in surface orientation, between the FRE point and Pokrovsky-Talapov (PT) type critical endpoints. The latter display anisotropic scaling with exponent $z=3$ instead of familiar PT value $z=2$.Comment: 12 pages, 19 figure

Control of macrophytes by grass carp (ctenopharyngodon idella) in a Waikato drain, New Zealand

Hornwort (Ceratophyllum demersum L.) and other aquatic macrophytes have historically been mechanically removed from the Rangiriri drain and Churchill East drain to maintain drain efficiency. As an alternative control method for the high plant biomass that accumulates at the end of summer, the effect of stocking diploid grass carp (Ctenopharyngodon idella L.) on the aquatic vegetation was evaluated in these Waikato drainage systems. At the start of the trial, both drains had a low diversity of aquatic macrophytes, and of the nine species (including the emergents), seven were exotic. Two months after grass carp were released to Churchill East drain (the treated drain) the four submerged and floating macrophyte species became scarce in the main drain. Over the same period, these species increased in biomass in Rangiriri drain (the untreated drain), where hornwort became dense and surface-reaching and remained so for the duration of the trial. However, grass carp did not control submerged vegetation in smaller side drains or the shallow, upper parts of the main drain, or the marginal sprawling species and emergent species. The cost of leasing the grass carp was similar to the cost of clearing the drains mechanically, but grass carp provided continuous weed control. However, subsequent to this trial, 62 dead grass carp were found in Churchill East drain in February 2001, and weed cover subsequently increased. This illustrates that grass carp management in New Zealand agricultural drains can be problematic due to periodic fish kills