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By analyzing COSMIC data, Sharma et al. (2010) found more than 50% reduction in electron density during a solar eclipse at the F2-layer and above, with the peak of similar to 70% at 370 km. So great eclipse effect on topside ionosphere was very abnormal and much different from previous studies. However, by comparing the cosmic data with IRI results, we find that the abnormal reduction comes mainly from the significant local time variation at sunrise, not from the eclipse effect. Furthermore, we simulated the eclipse effect by using a theoretical model to confirm our analysis. (C) 2011 Elsevier Ltd. All rights reserved.

With the advent of the World Wide Web (WWW), the way people publish, retrieve and synthesise information has totally changed. The Web is a hypertext system consisting of a huge amount of information which has very different forms. The concept of geospatial Web content emphasises the geospatial context of online information. Due to the continued explosive increase in the volume and complexity of geospatial Web content, it is necessary to have some mechanisms through which content can be systematically organised depending on their geospatial characteristics, and can be efficiently accessed and interrelated. This paper presents the design and development of Geo-coded Spatial Navigation System (G-SNS), a geo-referencing and browsing system that aims to provide an integrated user interface for navigation and browsing of geospatial Web content. Three case studies based on the G-SNS architecture in different application domains are developed and described: 1) Local News Reader categorises online news stories based on their geospatial context, 2) Web Sites Finder enables users to find Web sites that are close to users' current locations, and 3) Property List Map provides users with a map-based interface for searching and reviewing of real estate properties.

In order to evaluate the use of paper as a mulch for plant production, this research investigated the optical characteristics of two recycled papers (Emboss and Eco, beige 120 g/m2, and dark brown 55 g/m2, respectively) and a silver-polyethylene film (Silver, containing aluminum powder). We measured transmittance and reflectance of these materials as mulches under light controlled and open field (Tottori Sand Dune) conditions. Reflectance was defined as a ratio of reflective radiance of the mulch surface to that of the reflection standard surface.Used as mulches, all three materials would inhibit weed growth as they prevented the penetration of light at 660 nm, which stimulates weed germination. Mean transmittance at 400-700 nm for all three was less than 1%. The reflectance of Emboss and Eco was low for ultraviolet (350-400 nm). but high for visible (400-700 nm) and near infrared rays (700-2, 500 nm). The opposite was found with Silver. The radiances of the three mulches on fair and cloudy days were compared. The radiance of the three mulches on the cloudy day were high for ultraviolet but low for visible and near infrared rays. The light scattering property of each material was measured hemispherically at 5 angles: 30°, 60°, 90°, 120° and 150°. Silver reflected light more strongly in the direction against the angle of the sun. In contrast, Emboss generally reflected more light than Eco in all directions, both had no significant differences among the directions. Because Emboss reflects photosynthetically active radiation (400-700nm) at a wider angle than Silver, it may be better for plant photosynthesis.

A lifecycle assessment to estimate greenhouse gas emissions in Australia from the paper cycle is summarised. The greenhouse gas emissions from paper in Australia in 1999/2000 were estimated to be 12.1 million tonnes (Mt) of CO2 equivalent. Nearly half of this amount consisted of CH4 emissions from landfilled waste paper. Various waste management options were modelled to investigate the greenhouse impact of a tonne of paper over its whole lifecycle. Options that keep paper out of landfills significantly reduce greenhouse emissions, waste-to-energy recovery being most effective. Recycling is also beneficial, and is of particular interest from a management perspective because it can be controlled by the pulp and paper industry. These findings can be extended to other wood-based and organic wastes.

In the paper of A.G. Ryaboshapko [5], unfortunately, the author evaded the main question contained in the name of the paper criticized by him [4], namely, “Is Aerosol Scattering in the Stratosphere a Safety Technology Preventing Global Warming?” Instead of this, having named his paper “On the Taboo on Researching in the Field of Global Climate Geoengineering,” he discussed a completely different question which was not formulated by the authors. A thesis on “the taboo on researching” disputed by the author of the critical paper and the doubtfulness (from the point of view of the Russian science priorities) of some researches 1 discussed by us is far from being the same. In other words, not the actual position is under critique but that ascribed to the authors. Reverting to the discussion opened in [4], let us first of all specify its topic. A term “geoengineering” which came to us from the English-language literature embraces a wide range of various techniques of climate warming prevention. In order to preclude a potential confusion, in the report [7], for example, it is proposed to divide all kinds of climate regulation into two classes: techniques directed at the direct removal of CO2 from the atmosphere and techniques of the solar radiation control for the purpose of decreasing its absorption by the Earth’s surface. Recent investigations demonstrated that the use of technique of the second class is able to bring a large-scale damage to the environment and economic development of certain regions of the globe. These are the deliberate aerosol scattering in the stratosphere to control the solar radiation coming to the Earth’s surface and problems associated with this technique were discussed in our paper. Thus, the author of [5] substitutes the discussion of stratospheric aerosol scattering by the discussion of the great variety of techniques embraced usually by the general term “geoengineering” which we did not deal with. By the way, the authors avoided this term in [4] concentrating on the concrete technique.

Ash formation during industrial-scale bubbling fluidized bed (BFB) and circulating fluidized-bed (CFB) combustion of bark, waste wood and paper mill sludges has been studied. The principal ash formation mechanism was the sintering of 0.2–4 μ m paper filler mineral particles into larger, porous ash agglomerates from 10 to 200 μ m in size which dominated the fly ash total mass and specific surface area. Fly ash total mass concentration at the electrostatic precipitator inlet conditions varied from 4.5 g N -1 m -3 at BFB to 8.3 g N -1 m -3 at CFB while the respective total surface area concentrations as determined with nitrogen absorption were 32 and 83 m 2 N -1 m -3 . During bark combustion in the BFB, we observed an ultrafine mode at 0.05 μ m consisting of spherical particles and their chain-type agglomerates. Ultrafine mode mass and surface area concentrations were 3 and 0.1 m 2 N -1 m -3 , respectively, as determined with the electrical low-pressure impactor and with the differential mobility analyzer. Ultrafine particles were formed via nucleation of volatilized ash species followed by particle growth via collision and coalescence and via vapor condensation. During waste wood combustion in the CFB, ultrafine particle concentration was significantly lower than during bark combustion in BFB, indicating reduced ash volatilization during CFB combustion. When co-firing sludge with bark in the BFB and with waste wood in the CFB ultrafine particle concentration was further reduced. Results from continuous aerosol measurements by the electrical low-pressure impactor (ELPI), by the scanning differential mobility analyzer (SMPS) and by the tapered element oscillating microbalance (TEOM) as the function of BFB process conditions suggest that co-combustion of sludge reduces significantly the ultrafine particle formation rate. No significant enrichment of alkali and trace metals in the ultrafine particles was observed.

This short note is a reply to the comments by Le et al. (accepted for publication) on the paper by Sharma et al. (2010) that is concerned with the eclipse time observation of ionospheric TEC and electron density.

Massman in his paper derives an analytical formula for eddy covariance flux corrections, based on equivalent first-order co-spectral transfer functions both at low and high frequencies. At low frequencies flux attenuation due to digital recursive filtering, frequently applied in eddy covariance systems for trend removal, and spectral cut off due to finite averaging time were considered. This comment discusses the form of the transfer function of high-pass digital recursive filter and consequences of block averaging on flux estimate.

In this paper several statements of Kandlikar and Ramachandran concerning the one-to-one correspondence between the spectrometric channels and aerosol size classes, overlaps of the kernels of integral equation, errors of the algebraic systems’ solutions and some inversion algorithms are discussed. It is shown that expression A −1 e ( A -linear algebraic system matrix, e -vector of the experimental errors) cannot be interpreted as the standard deviation of random errors and its adequate interpretation is given. The expressions for standard deviation of the system's solution are derived using the error propagation formula. It is indicated that known inequality for the errors of linear systems’ solutions including condition number of matrix cond is not applicable to the random errors, and the new inequality is given. The approach of smooth continuous size distribution function concept is shown to meet with difficulties since its actual realization is discrete, stochastic and has only two values: 0 and 1.

International audience; No abstract available

High ozone levels are regularly reached during summer period in South-European urban areas, calling for careful design of primary pollutants emission reduction strategies. In this perspective the CALGRID modelling system has been applied to Milan metropolitan area, located in the Po Valley, the most industrialised and populated area in Italy. For the first modelling exercise, a simulation domain of 100×100 km2 has been considered and a summer period, characterised by high photochemical activity, has been selected. Hourly emissions have been derived by spatially and temporally disaggregating national inventories data, while standard upper-air and ground-based meteorological data have been used as input to the CALMET pre-processor. A careful analysis of simulation results versus local network monitoring data has revealed some critical points, related to both modelling assumptions and practical data availability. A satisfactory reproduction of daytime ozone behaviour has been, in fact, accomplished, both in urban and suburban sites, while nighttime primary pollutants accumulations and consequent ozone consumption simulated by the model have not found correspondence in the measurements. Nitrogen dioxide has been also successfully modelled, mostly in city surroundings, whereas higher discrepancies have been found in some urban stations. Possible explanations of these facts are discussed in the paper, giving an insight for further work.

Anders K. Angstrom was known primarily for his contributions to the field of atmospheric radiation. However, his scientific interests encompassed many diverse topics. This paper describes the contents of two early, remarkable, and, until recently, largely unknown papers by Angstrom on probability forecasting and the use/value of weather forecasts. These papers, entitled “Sannolikhet och Praktisk Vaderleksprognos” (“Probability and Practical Weather Forecasting”) and “On the Effectivity of Weather Warnings,” were published in 1919 and 1922, respectively. Noteworthy features of these two papers include 1) a discussion of the sources of uncertainty in weather forecasting, 2) discourses on the problems of estimating probabilities by means of empirical relative frequencies and forecasters' subjective judgments, 3) the use of a Gaussian model to describe the accuracy of minimum temperature forecasts, 4) the identification of the ratio of the protection costa to the “risked value” if protective action is not tak...

We examine the analysis by Lee (1998) of the scalar conservation budget in advective flows. Lee treated the budget in a one-dimensional framework, neglected horizontal derivatives of turbulent quantities and proposed that mean flow advection, simplified to its vertical component, can be used to improve budget closure, when data from only a single tower are available. We conclude: • that the appropriate analysis framework for constructing such budgets is unavoidably two- or three-dimensional because 2D and 3D mean velocity fields always induce streamwise variation in the eddy fluxes of scalars. • that in such flow fields it is generally incorrect to assume that the vertical component of advection w ∂ c /∂z is everywhere much larger than the horizontal component u ∂ c /∂x The vertical component can only provide a good measure of total advective flux divergence in the special circumstance where the tower is located beneath the vertical stagnation streamline of a recirculating flow. By referring to a linear model of scalar transport over a hill we show that the relationship between u ∂ c /∂x and w ∂ c /∂z is entirely dependent on particular flow conditions and that, in general, w ∂ c /∂z cannot even be used to provide a bound on the magnitude of total advection. • that for measurements at heights small compared to the horizontal scale of the advective flow, the horizontal gradient of turbulent flux ∂ u’c’ /∂x can probably be neglected relative to its vertical equivalent ∂ w’c’ /∂z and, • by using simple hydrodynamic models of 2D flows it can be shown that the vertical gradient of mean vertical velocity is approximately constant over tower heights small compared to the horizontal scale of the advective flow. We also comment on the proper choice of coordinate frame for analysis.

While conducting a randomized seeding experiment, a storm was selected whose microphysical characteristics were so far from what was expected, given the existing thermodynamic environment, that some explanation was needed to account for the apparent errant behavior of this storm. More than a decade of sampling at −10°C using the project Lear jet has led to a simple classification technique, based on cloud-base temperature and buoyancy, which predicts the absence or presence, and to some extent the degree of coalescence (coalescence-freezing) precipitation growth in local convective storms. The unusual nature of this storm was recognized against this extensive microphysical database. The probable cause is attributed to emissions from a Kraft paper mill 10 km south of the storm's position. The mill had recently undergone an expansion program that had quadrupled its output of paper products. Using the radar characteristics of this unusual storm as a guide, a search of one season of radar data reveal...

Relationship between latex yield of natural rubber trees (Hevea brasiliensis) and climatic variables have been derived. Under humid tropical rainfed conditions, observed latex yields of rubber trees (clone RRII 105) are highly variable from 19.8 to 90.5 g per tree per tap. Maximum temperature experienced during 1 day, 7 days and 30 days prior to the tapping explains about 32%, 42% and 64%, respectively, of the day-to-day variability in latex yields. The multiple regression models to estimate latex yield on a tapping day, with different antecedent weather conditions are developed. The weekly weather conditions associated with optimum yields were maximum temperature of 30.4°C, minimum temperature of 22.8°C, 5.9 h sunshine and 72 mm of rainfall. Any deviation from these meteorological conditions up to 6 months duration may significantly influence latex production. In general, maximum temperature, sunshine duration, vapour pressure deficit and pan evaporation showed significant negative correlation with yield, irrespective of the time period considered. Whereas, significant positive association was observed between rainfall beyond a month period and the latex yield of rubber trees.

Gardner (1996, henceforth G96), examines a number of theories that seek to account for the vertical-wavenumber (m) spectrum of horizontal wind perturbations (u′) induced by gravity waves in the middle atmosphere. He notes that all the theories predict much the same spectra, and so he seeks to “identify the experimental data required to test the fundamental physics upon which these theories are based …” While I applaud Gardner's goal and will at a later stage contribute to it, I must first comment adversely on some aspects of his preliminary summaries and of his observational inferences. My remarks are limited almost exclusively to his discussion of the linear instability theory of Dewan and Good (1986, henceforth DG86) and Smith et al. (1987, henceforth SFV87), called by him the LIT, the diffusive filtering theory (DFT) of Gardner (1994, henceforth G94), and the Doppler spread theory (DST) initiated by Hines (1991b). In all of the theories under discussion, the u′ power spectral density (PSD) is taken in G96 to exhibit an increase with m at m values less than some characteristic value m∗ and a decrease, more-or-less proportional to m−3, in a ‘tail’ region at greater m values up to some upper limit mM, whereafter turbulence is said to set in. The transition at m∗ may be thought of, for convenience of discussion, as being abrupt, though each theory in fact either assumes or derives a smooth transition. The various theories differ from one another in the physical processes that are assumed to establish the tail portion of the spectrum, the tail's range in m, and the intensity of the PSD of the tail. That intensity has been said observationally to be invariant under changes of circumstance and height, a characteristic that is widely attributed to a ‘saturation’ of the spectrum or of the corresponding waves. The tail portion of the spectrum is therefore said by many to be saturated, though the theory of G94 purports to disagree with this concept and in fact provides possible alternatives to the m−3 form (as, indeed, does DG86). The LIT, DFT and DST will be discussed below in sequence.

If stratospheric temperature trends are to be understood, coupled chemistry climate models will need to be run. Simulations with fixed ozone trends might provide a misleading indication of future temperature trends. Copyright © 2005 Royal Meteorological Society

It has recently been brought to our attention by members of the scientific community that a paper published in Climate (ISSN 2225-1154, https://www.mdpi.com/journal/climate) has raised some controversy regarding its originality, overall quality, and the scientific validity of the data presented. Moreover, two members have resigned from the Editorial Board, stating they are not willing to be associated with a journal where such articles are published. The paper they referred to was “Akasofu, S.-I. On the Present Halting of Global Warming. Climate 2013, 1, 4–11”, published in the first issue of Climate in May 2013 [1], available online at: https://www.mdpi.com/2225-1154/1/1/4. [...]

Some additional data are given for the development of solar-terrestrial physics during the 19th and 20th centuries.

The discussion reviews the prevailing pattern of energy demand and supply in the MINK states, speculates on the region's long-term energy future in the absence and presence of greenhouse warming, and, in the latter case, considers energy sector adaptation to such a prospect. Climate-sensitive energydemand is dominated by heating and cooling in various sectors of the regional economy (around 20% of regional energy consumption) and by such agricultural applications as irrigation pumping and crop drying (around 5%). A climate-sensitive energysupply issue of some importance is the region's partial dependence on hydroelectric capacity in the upper Missouri river basin. The analysis finds that, unlike the rather significant impacts likely to be experienced by other sectors of the regional economy, the hypothesized warming trend will translate into only small net increases in energy demand; and that technological possibilities and policy measures are available to mute any serious climatic effects on the energy sector.

The impacts of climate change on the agricultural, energy, forestry, and water sectors of MINK would reverberate negatively throughout the regional economy. Allowing for sectoral adjustments to the new climate, however, the decline in regional income and production would not likely exceed 1–2%. The largest economy-wide impacts would be by way of the agricultural and water sectors. The impacts by way of forestry and energy would be negligible, unless the nation adopts a program of massive reforestation to capture CO2, which would positively affect the regional economy.

The adaptability of forests in the U.S. midwest to a changing climate is assessed. The forests of Missouri are simulated with a ‘forest-gap’ model, a stochastic model of the annual growth and mortality of trees within mixed-species forest plots. The development of representative forest plots under an analog climate like that of the 1930s is compared to development under baseline climate conditions. With no management response, average forest biomass in the region declines by 11% within ten years, primarily due to moisture-stress induced mortality. Longer term declines in forest productivity on the order of 30% are simulated. A variety of possible management responses through planting or harvesting practices were evaluated. None of these adaptations appear to be practical, although the salvage harvest of stressed trees would offset the economifc losses associated with the early mortality. An investigation of anticipated trends in the broader forest products sector suggests that opportunities for further adaptation to offset the decline in primary productivity of this region's forest are quite limited. However, a shift to wood powered electrical generation in the region might justify a level of management that would allow some adaptation to the analog climate change.

A four step methodology has been developed for study of the regional impacts of climate change and the possible responses thereto. First the region's climate sensitive sectors and total economy are described (Task A, current baseline). Next a scenario of climate change is imposed on the current baseline (Task B, current baseline with climate change). A new baseline describing the climate sensitive sectors and total regional economy is projected for some time in the future (Task C, future baseline, year 2030) in the absence of climate change. Finally, the climate change scenario is reimposed on the future baseline (Task D, future baseline with climate change). Impacts of the climate change scenario on the current and future regional economies are determined by means of simulation models and other appropriate techniques. These techniques are also used to assess the impacts of an elevated CO2 concentration (450 ppm) and of various forms of adjustments and adaptations.

The climate of the 1930s was used as an analog of the climate that might occur in Missouri, Iowa, Nebraska and Kansas (the MINK region) as a consequence of global warming. The analog climate was imposed on the agriculture of the region under technological and economic conditions prevailing in 1984/87 and again under a scenario of conditions that might prevail in 2030. The EPIC model of Williamset al. (1984), modified to allow consideration of the yield enhancing effects of CO2 enrichment, was used to evaluate the impacts of the analog climate on the productivity and water use of some 50 representative farm enterprises. Before farm level adjustments and adaptations to the changed climate, and absent CO2 enrichment (from 350 to 450 ppm), production of corn, sorghum and soybeans was depressed by the analog climate in about the same percent under both current and 2030 conditions. Production of dryland wheat was unaffected. Irrigated wheat production actually increased. Farm level adjustments using low-cost currently available technologies, combined with CO2 enrichment, eliminated about 80% of the negative impact of the analog climate on 1984/87 baseline crop production. The same farm level adjustments, plus new technologies developed in response to the analog climate, when combined with CO2 enrichment, converted the negative impact on 2030 crop production to a small increase. The analog climate would have little direct effect on animal production in MINK. The effect, if any, would be by way of the impact on production of feed-grains and soybeans. Since this impact would be small after on-farm adjustments and CO2 enrichment, animal production in MINK would be little affected by the analog climate.

The winner of the Journal of Spatial Science award for the Best Research and Review Paper in 2013 is Improving Lidar-based Forest Structure Mapping with Crown-level Pit Removal, published in Volume...

Original editorial can be found at: http://www.sciencedirect.com/ Copyright Elsevier [Full text of this paper is not available in the UHRA]