Increasing fiscal resilience to disasters in the Pacific

Pacific Island countries are among the list of countries that face the highest disaster risk globally—in per capita terms. In recent years, governments in the region have been confronted by a rise in damages from extreme catastrophic events, many increasingly linked to climate change. These events pose significant challenges to Pacific governments in terms of maintaining fiscal stability and the operation of their limited and under-diversified economies and shallow financial sectors. Governments in the region generally play a leading role in domestic economies and are responsible for leading disaster prevention, mitigation, and recovery efforts. Accordingly, measures to improve financial sustainability and the public sector’s ability to provide public services in the aftermath of major disasters must be prioritized. This paper examines the literature on fiscal resilience to disasters, the estimated impacts of major events in the Pacific, and analyses the applicability of available financial instruments to facilitate both ex ante and ex post disaster fiscal risk management in the region. The paper also discusses policies that can improve resilience against fiscal risks.

     

Adsorption of dissolved phosphate onto loess particles in surface and deep Eastern Mediterranean water

The objective of this study was to examine whether dissolved inorganic phosphate (DIP) is removed from the Eastern Mediterranean Sea by adhering to atmospherically deposited loess particles sinking through the water column. In a series of radiolable experiments, loess from the Negev Desert, treated in various ways, was added to surface (SSW) and deep (DSW) seawater spiked with ³²PO₄⁻³. It was shown that when fresh loess reaches the Mediterranean SSW approximately 1.3 μmol P/g are released (11% of the total P concentration). Biological activity and inorganic particles removed similar amounts of the tracer (30–40%) from SSW. It was estimated that about 0.2 μmol P/g of ‘aged loess' (proxy of particles sinking into DSW), were removed from poisoned SSW and DSW, while there was minor adsorption when either nothing or quartz powder was added. The adsorbed DIP accounts for approximately 15% of the released P and is equivalent to about 2% of the remaining P (11.17 μmol P/g loess). Therefore, the process of DIP removal by atmospherically derived particles exists, but due to the higher release of P, the result is a net addition of dissolved atmospheric phosphorus in seawater. It is postulated that in actual SSW where dust concentrations are much lower, biological uptake out-competes inorganic adsorption, although it was demonstrated that the decrease in loess particle concentrations tends to increase their adsorption capacity. As the loess descends into the DSW it continues to remove DIP and thus transports phosphate from the water column to the sediments. A preliminary quantitative estimate suggests that the process of DIP removal by loess particles cannot explain the phosphate ‘deficit' in the Eastern Mediterranean DSW characterized by unusually high DIN/DIP ratios (27) reported by others.     

Real-time measurement of volcanic SO2 emissions: validation of a new UV correlation spectrometer (FLYSPEC)

A miniaturized, lightweight and low-cost UV correlation spectrometer, the FLYSPEC, has been developed as an alternative for the COSPEC, which has long been the mainstay for monitoring volcanic sulfur dioxide fluxes. Field experiments have been conducted with the FLYSPEC at diverse volcanic systems, including Masaya (Nicaragua), Poás (Costa Rica), Stromboli, Etna and Vulcano (Italy), Villarica (Chile) and Kilauea (USA). We present here those validation measurements that were made simultaneously with COSPEC at Kilauea between March 2002 and February 2003. These experiments, with source emission rates that ranged from 95 to 1,560 t d⁻¹, showed statistically identical results from both instruments. SO₂ path-concentrations ranged from 0 to >1,000 ppm-m with average correlation coefficients greater than r ²=0.946. The small size and low cost create the opportunity for FLYSPEC to be used in novel deployment modes that have the potential to revolutionize the manner in which volcanic and industrial monitoring is performed.     

Photochemical aerosols in Titan's atmosphere

The optical properties of polymers, produced photolytically from ethylene, which was detected in Titan's atmosphere and from acetylene or hydrogen cyanide which may be present there, were studied experimentally. It is shown that an aerosol consisting of polyethylene provides an excellent fit to the variation of Titan's albedo with wavelength, while polymers of acetylene or hydrogen cyanide do not. This fit seems to remove the requirement of nitrogen-bearing polymers, which was proposed earlier to account for Titan's red coloration. Therefore, Titan's coloration does not necessarily imply the presence of nitrogen in its atmosphere. It is also proposed that above the layer of larger aerosol particles, whose scattering determines the phase function, there are smaller particles of the same material, which act as an absorbing haze to darken and slightly redden the underlying aerosol. This high-altitude haze also causes the observed strong limb-darkening.     

Inhomogeneous models of Titan's aerosol distribution

A model of Titan's aerosol is presented which allows the particle size to vary with height. The model assumes a refractive index appropriate to an ethylene polymer and a mass flux independent of height equal to the value derived from laboratory measurements. The free parameters of the model are determined by fitting to the observed geometric albedo at 4000 and 6000 Å. A methane spectrum is derived which is in excellent agreement with observations. An aerosol optical depth of ～5 is found in the visible, with the particle radius varying from 0.01 to 8 μm. The presence of an optically thick methane cloud at the temperature minimum is indicated.     

Regional effects of natural disasters in China: investing in post-disaster recovery

We examine the effects of natural disasters on income and investment in China. Using macroeconomic province-level data and the provincial history of disaster exposure over the past two decades, we describe the relationship between disaster mortality and morbidity, disasters’ economic damages, government investment and regional economic activity, and infrastructure development. The Chinese government’s aggressive investment in post-disaster reconstruction is discussed, and the implications of this investment for post-disaster private sector economic activity are analyzed empirically. We further investigate the differential effects of natural disasters on economic activity in China’s diverse geographical regions.     

Mass dependent stable isotope fractionation of mercury during mer mediated microbial degradation of monomethylmercury

Controlling bioaccumulation of toxic monomethylmercury (MMHg) in aquatic food chains requires differentiation between biotic and abiotic pathways that lead to its production and degradation. Recent mercury (Hg) stable isotope measurements of natural samples suggest that Hg isotope ratios can be a powerful proxy for tracing dominant Hg transforming pathways in aquatic ecosystems. Specifically, it has been shown that photo-degradation of MMHg causes both mass dependent (MDF) and mass independent fractionation (MIF) of Hg isotopes. Because the extent of MDF and MIF observed in natural samples (e.g., fish, soil and sediments) can potentially be used to determine the relative importance of pathways leading to MMHg accumulation, it is important to determine the potential role of microbial pathways in contributing to the fractionation, especially MIF, observed in these samples. This study reports the extent of fractionation of Hg stable isotopes during degradation of MMHg to volatile elemental Hg and methane via the microbial Hg resistance (mer) pathway in Escherichia coli carrying a mercury resistance (mer) genetic system on a multi-copy plasmid. During experimental microbial degradation of MMHg, MMHg remaining in reactors became progressively heavier (increasing δ²⁰²Hg) with time and underwent mass dependent Rayleigh fractionation with a fractionation factor α_202/198 = 1.0004 ± 0.0002 (2SD). However, MIF was not observed in any of the microbial MMHg degradation experiments indicating that the isotopic signature left by mer mediated MMHg degradation is significantly different from fractionation observed during DOC mediated photo-degradation of MMHg. Additionally, a clear suppression of Hg isotope fractionation, both during reduction of Hg(II) and degradation of MMHg, was observed when the cell densities increased, possibly due to a reduction in substrate bioavailability. We propose a multi-step framework for understanding the extent of fractionation seen in our MMHg degradation experiments and, based on estimates of the rates of the various steps involved in this mer mediated pathway, suggest which steps in the process could contribute towards the observed extent of fractionation. This framework suggests that at lower cell densities catalysis by MerB was the rate limiting step while at higher cell densities transport into the cell, which does not cause fractionation, became the rate limiting step. In addition to presenting evidence for absence of MIF during mer mediated Hg transformations, based on the nature of Hg compounds and microbe-Hg interactions, we suggest that the nuclear spin dependent MIF (i.e., the magnetic isotope effect) is also unlikely to occur during other non mer mediated ‘dark’ microbial Hg transformations (e.g., formation of MMHg and oxidative degradation of MMHg). Because of the important implications of the absence of MIF during biological processes on Hg isotope systematics, we discuss theoretical considerations and experimental strategies that could be used to confirm this suggestion.