Implications of Country-Level Decisions on the Specification of Crown Cover in the Definition of Forests for Land Area Eligible for Afforestation and Reforestation Activities in the CDM

Within the Kyoto Protocol, countries have significant latitude to define a forest. The most important parameter affecting area designated as forest is the minimum crown density which can be set between 10 and 30 percent. The choice will have implications for the amount of land available in a country for afforestation and reforestation (A/R) activities within the Clean Development Mechanism (CDM). In this paper, we used GIS analysis to look at four case studies from countries involved in the EU-funded ENCOFOR project: Bolivia, Ecuador, Uganda and Kenya. We also looked at the effects of other factors that would exclude land from eligibility for A/R projects. A low threshold of 10 percent crown cover resulted in exclusion of 70 to 90 percent of the land area of all countries except Kenya, which differed from the other countries by its large dryland areas. Much less area was excluded when higher thresholds were used. The spatial analyses showed not only the effects of the choice of the crown cover criterion, but also where the land was available for CDM activities within each country at different thresholds. This is the first time that the effect of the crown cover element of the Kyoto forest definition on land availability and distribution for CDM A/R activities has been quantified. While there are a number of reasons to choose different thresholds, this analysis suggests that countries that are considering using CDM finance for rural development might want to select the higher minimum threshold for crown cover in order to maximize their participation and flexibility.     

Identification of typical synoptic patterns causing heavy rainfall in the rainy season in Japan by a Self-Organizing Map

In order to systematically and visually understand well-known but qualitative and complex relationships between synoptic fields and heavy rainfall events in Kyushu Islands, southwestern Japan, during the BAIU season, these synoptic fields were classified using the Self-Organizing Map (SOM), which can convert complex non-linear features into simple two-dimensional relationships. It was assumed that the synoptic field patterns could be simply expressed by the spatial distribution of (1) wind components at the 850 hPa level and (2) precipitable water (PW) defined by the water vapor amount contained in a vertical column of the atmosphere. By the SOM algorithm and the clustering techniques of the U-matrix and the K-means, the synoptic fields could be divided into eight kinds of patterns (clusters). One of the clusters has the notable spatial features represented by a large PW content accompanied by strong wind components known as low-level jet (LLJ). The features of this cluster indicate a typical synoptic field pattern that frequently causes heavy rainfall in Kyushu during the rainy season.In addition, an independent data set was used for validating the performance of the trained SOM. The results indicated that the SOM could successfully extract heavy rainfall events related to typical synoptic field patterns of the BAIU season. Interestingly, one specific SOM unit was closely related to the occurrence of disastrous heavy rainfall events observed during both training and validation periods. From these results, the trained SOM showed good performance for identifying synoptic fields causing heavy rainfall also in the validation period. We conclude that the SOM technique may be an effective tool for classifying complicated non-linear synoptic fields and identifying heavy rainfall events to some degree.     

Persistence of vinyl chloride in ground water at the Woodlawn landfill Superfund site,northeastern Maryland,USA

Since landfill operations ceased in the early 1980s at the Woodlawn landfill Superfund site in northeastern Maryland, USA, the carcinogen vinyl chloride monomer (VCM) has persisted in the site ground water at concentrations in places greater than 100 ppb. Investigations of VCM concentrations from monitoring well data from 1981 through 1991, which were published in 2001, concluded that concentrations were cyclic and were not dissipating. Data from 1991 to 2000 confirm VCM persistence, showing concentration peaks as late as 1997 in the eastern part of the site. These values are significantly above both drinking water standards (>MCL of 2 ppb) and lifetime excess cancer risk (E-6 risk level) from exposure since birth (>0.024 ppb). Sources for VCM are landfill wastes (PVC-sludge) and effluent from an on-site transfer station. In addition to direct release of VCM from wastes, other chlorinated hydrocarbons, trichloroethene and perchloroethene (TCE and PCE) are also present in the ground water, and these compounds can degrade into VCM. Persistence of VCM concentrations is the result of leachate generation, mostly from multi-source wastes in the vadose zone, with subsequent infiltration into the regional aquifer. Increases in VCM concentrations (new leachate generation) alternated with decreases in VCM concentrations (infiltration without leachate) in a cyclic fashion, during this 20-year period.     

Estimating the influence of increased nitrate loads from wastewater on phosphorus mobility in river sediments

Research on the sediment‐surface water transition zone in three study site regions, different in hydrological conditions, was conducted to estimate to which extent nitrate in surface water can contribute to riverbed sediment oxidation and thus prevent release of sediment phosphorus to surface water. Consequently, the Du tch Flow Model (DUFLOW) based water quality model “Spreewald” and results from the emission model “ Mo delling N utrient E missions in Ri ver S ystems” (MONERIS) were used to estimate to which extent wastewater treatment plants (WWTPs) could contribute to the NO₃^– concentration in surface waters if they were operated without denitrification. It is demonstrated that an effective phosphorus retention in sediments by means of surface water NO₃^– is possible only under specific conditions, i. e. (i) a sufficient supply of surface water to the sediment by advective fluxes, (ii) a sufficient amount of sediment iron to provide phosphorus binding sites in the case of sediment oxidation, (iii) a redox system not leading to a rapid NO₃^– and FeOOH depletion and to phosphorus release from organic pools by high microbial activities. Model results show that in‐stream denitrification processes counteract a significant increase of NO₃^– surface water concentrations from WWTPs operated without denitrification during summer, when eutrophication risk through phosphorus is highest. The increase of NO₃^– surface water concentrations in winter due to decreased denitrification in the surface water is of minor relevance for phosphorus release from sediments.     

A magnetotelluric study of the Damara Belt in Namibia: 2. MT phases over 90° reveal the internal structure of the Waterberg Fault/Omaruru Lineament

Magnetotelluric (MT) observations at some sites in the vicinity of the Waterberg Fault/Omaruru Lineament (WF/OL), a major tectono-stratigraphic zone boundary in the Central Zone of the Damara Belt, show evidence for strong three-dimensional (3D) effects. We observe very high skew values, phases over 90°, and a strong correlation of parallel components of the electric and magnetic fields at long periods. Because of the dense site spacing and good spatial coverage, we can positively attribute these effects to local geology and are able to resolve structural detail within the WF/OL. Mapping LaTorraca’s electric characteristic vectors in form of ellipses proved particularly useful in identifying key elements of the conductivity structure for subsequent modelling. 3D and 2D anisotropic modelling can reproduce most of the observed 3D effects. The conductivity anomalies revealed in the area are: (i) a conductive ring structure in the shallow crust along the northern part of the profile; (ii) an anisotropic region in the upper crust with high conductivity parallel to the WF/OL; (iii) anisotropy in the lower crust with a different but undetermined strike direction; and (iv) a shallow elongated conductor sub-normal to the WF/OL. Modelling studies further suggest that the (anisotropic) fault zone is approximately 10 km wide and may reach down to a depth of 14 km or more.     

Wavelets and the Generalization of the Variogram

The experimental variogram computed in the usual way by the method of moments and the Haar wavelet transform are similar in that they filter data and yield informative summaries that may be interpreted. The variogram filters out constant values; wavelets can filter variation at several spatial scales and thereby provide a richer repertoire for analysis and demand no assumptions other than that of finite variance. This paper compares the two functions, identifying that part of the Haar wavelet transform that gives it its advantages. It goes on to show that the generalized variogram of order k=1, 2, and 3 filters linear, quadratic, and cubic polynomials from the data, respectively, which correspond with more complex wavelets in Daubechies's family. The additional filter coefficients of the latter can reveal features of the data that are not evident in its usual form. Three examples in which data recorded at regular intervals on transects are analyzed illustrate the extended form of the variogram. The apparent periodicity of gilgais in Australia seems to be accentuated as filter coefficients are added, but otherwise the analysis provides no new insight. Analysis of hyerpsectral data with a strong linear trend showed that the wavelet-based variograms filtered it out. Adding filter coefficients in the analysis of the topsoil across the Jurassic scarplands of England changed the upper bound of the variogram; it then resembled the within-class variogram computed by the method of moments. To elucidate these results, we simulated several series of data to represent a random process with values fluctuating about a mean, data with long-range linear trend, data with local trend, and data with stepped transitions. The results suggest that the wavelet variogram can filter out the effects of long-range trend, but not local trend, and of transitions from one class to another, as across boundaries.     

UV Observations with the Transition Region and Coronal Explorer

The Transition Region and Coronal Explorer is a space-borne solar telescope featuring high spatial and temporal resolution. TRACE images emission from solar plasmas in three extreme-ultraviolet (EUV) wavelengths and several ultraviolet (UV) wavelengths, covering selected ion temperatures from 6000 K to 1 MK. The TRACE UV channel employs special optics to collect high-resolution solar images of the H i L line at 1216 Å, the C iv resonance doublet at 1548 and 1550 Å, the UV continuum near 1550 Å, and also a white-light image covering the spectrum from 2000–8000 Å.We present an analytical technique for creating photometrically accurate images of the C iv resonance lines from the data products collected by the TRACE UV channel. We use solar spectra from several space-borne instruments to represent a variety of solar conditions ranging from quiet Sun to active regions to derive a method, using a linear combination of filtered UV images, to generate an image of solar C iv 1550 Å emission. Systematic and statistical error estimates are also presented. This work indicates that C iv measurements will be reliable for intensities greater than 1014 photons s–1 cm–2 sr–1. This suggests that C iv 1550 Å images will be feasible with statistical error below 20% in the magnetic network, bright points, active regions, flares and other features bright in C iv. Below this intensity the derived image is dominated by systematic error and read noise from the CCD.     

The topology of the IRAS Point Source Catalogue Redshift Survey

We investigate the topology of the new Point Source Catalogue Redshift Survey (PSCz) of IRAS galaxies by means of the genus statistic. The survey maps the local Universe with approximately 15 000 galaxies over 84.1 per cent of the sky, and provides an unprecedented number of resolution elements for the topological analysis. For comparison with the PSCz data we also examine the genus of large N -body simulations of four variants of the cold dark matter (CDM) cosmogony. The simulations are part of the Virgo project to simulate the formation of structure in the Universe. We assume that the statistical properties of the galaxy distribution can be identified with those of the dark matter particles in the simulations. We extend the standard genus analysis by examining the influence of sampling noise on the genus curve and introducing a statistic able to quantify the amount of phase correlation present in the density field, the amplitude drop of the genus compared to a Gaussian field with identical power spectrum. The results for PSCz are consistent with the hypothesis of random-phase initial conditions. In particular, no strong phase correlation is detected on scales ranging from 10 to 32 h ⁻¹ Mpc, whereas there is a positive detection of phase correlation at smaller scales. Among the simulations, phase correlations are detected in all models at small scales, albeit with different strengths. When scaled to a common normalization, the amplitude drop depends primarily on the shape of the power spectrum. We find that the constant-bias standard CDM model can be ruled out at high significance, because the shape of its power spectrum is not consistent with PSCz. The other CDM models with more large-scale power all fit the PSCz data almost equally well, with a slight preference for a high-density τCDM model.