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The thermal field within the firn layer on the Greenland Ice Sheet (GrIS) governs meltwater retention processes, firn densification with surface elevation change, and heat transfer from the surface boundary to deep ice. However, there are few observational data to constrain these processes with only sparse in situ temperature time series that does not extend through the full firn depth. Here, we quantify the thermal structure of Western Greenland's firn column using instrumentation installed in an elevation transect of boreholes extending to 30 and 96 m depth. During the high‐melt summer of 2019, heat gain in the firn layer showed strong elevation dependency, with greater uptake and deeper penetration of heat at lower elevations. The bulk thermal conductivity increased by 15% per 100 m elevation loss due to higher density related to ice layers. Nevertheless, the conductive heat gain remained relatively constant along the transect due to stronger temperature gradients in the near surface firn at higher elevations. The primary driver of heat gain during this high melt summer was latent heat transfer, which increased up to ten‐fold over the transect, growing by 34 MJ m−2 per 100 m elevation loss. The deep‐firn temperature gradient beneath the seasonally active layer doubled over a 270‐m elevation drop across the study transect, increasing heat flux from the firn layer into deep ice at lower elevations. Our in situ firn temperature time series offers observational constraints for modeling studies and insights into the future evolution of the percolation zone in a warmer climate. Plain Language Summary: We address understudied aspects of the temperature field within the firn layer of the Greenland Ice Sheet (GrIS). Firn is snow that is in transition to glacier ice and its temperature is important to surface elevation changes, refreezing of meltwater, and ice flow properties. Our research deployed instrumentation in boreholes extending to depths of 30 and 96 m across an elevation transect in Western Greenland. During the high‐melt summer of 2019, we observed a pronounced spatial gradient in the thermal structure of the firn layer such that as elevation decreases, there is greater heat uptake, deeper heat penetration, and higher heat flux to deep ice. Despite increasing thermal conductivity with elevation loss, conductive heat gain remained relatively constant along the transect due to stronger and sustained temperature gradients in near‐surface firn at higher elevations. Notably, latent heat transfer from refreezing meltwater was the primary driver of heat gain, increasing up to ten‐fold across the transect with a growth rate of 34 MJ m−2 per 100 m elevation loss. Our in situ firn temperature time series not only provide valuable constraints for modeling studies but also offer insights into the prospective evolution of the percolation zone in a warmer climate. Key Points: Temperatures in boreholes up to 96 m depth in Greenland's percolation zone reveal strong time/space gradients in heat‐transfer mechanismsLatent heat transfer causes deeper and greater summer heat uptake at lower elevations, but conductive heat gain remains nearly constantDeep firn temperature gradients steepen sharply as elevation decreases, causing greater heat flux from the firn layer to the underlying ice [ABSTRACT FROM AUTHOR]

This study examines the relation between managerial ability and bond credit rating changes. We attempt to add to the credit rating agency literature by exploring the role managerial ability plays in the initial bond rating assignments and in rating changes. We predict firms with more‐able managers are more likely to have higher bond ratings and to be more able to have a positive influence on rating changes. We find a significant and positive relation between managerial ability and change in credit ratings, suggesting that more‐able managers can take effective actions to improve their credit ratings. [ABSTRACT FROM AUTHOR]

The link between subglacial hydrology and basal sliding has prompted work on basal hydrology models with water pressure and drainage capacity as prognostic variables. We find that the Glacier Drainage System model, which belongs to a commonly used family of subglacial hydrology models that include both channelized and distributed drainage components, underpredicts winter water pressure when compared to borehole observations from western Greenland given a wide range of plausible parameter values and inputs. This problem, though previously noted by other modelers, has not been addressed. Possible causes for the discrepancy including idealized model inputs or unconstrained parameters are investigated through a series of modeling experiments on both synthetic and realistic ice sheet geometries. Numerical experiments reveal that englacial storage and hydraulic conductivity in the distributed system are the primary controls on winter water pressure in Glacier Drainage System model. Observations of temperate layer thickness and englacial water content from western Greenland imply an upper bound on englacial storage, suggesting that a reduction in hydraulic conductivity is the most plausible cause of high winter water pressure. We conclude that hydraulic conductivity acts as a proxy for the subgrid‐scale connectivity of the linked cavity system and should therefore change seasonally in correspondence with melt water availability. [ABSTRACT FROM AUTHOR]

Ice in the ablation zone of the Greenland ice sheet is known to contain vertical temperature gradients that arise from conduction at the boundaries, the addition of strain and latent heat, and advective heat transport. A three-dimensional array of temperature measurements in a grid of boreholes reveals horizontal ice temperature gradients that challenge the present conceptualization of heat transfer. We measure two distinct types of temperature variability in the horizontal direction, one impacting a confined region where ice temperatures span a range of 5°C, and another with temperatures consistently varying by approximately 2°C across the entire 3-D block. We suggest the first demonstrates the localized and limited nature of latent heat input, and the second demonstrates that vertical heat advection outpaces diffusion. These findings imply that ice flow is highly variable over sub-ice-thickness length scales, which in turn generates contrasts in ice temperature that may impact ice deformation and fracturing. [ABSTRACT FROM AUTHOR]

The chemical composition of sediment sampled from a network of ice boreholes contacting the bed of the ablation zone of the Greenland Ice Sheet is compared to the composition of intact bedrock clasts. This sediment is enriched in silica and depleted in reactive cations compared to the underlying bedrock. In order to test whether these differences result from grain size biases either in sample collection or due to natural sorting, sediment samples were analyzed by grain size aliquots. Enrichment of silicon and depletion of cations is consistent across grain size classes and the compositions of bedrock and subglacial sediment are statistically separate. The difference in composition between subglacial sediment and rock aligns closely with the composition of dissolved solutes in waters sampled from the same field sites and is dissimilar to the composition of the sites' suspended sediment. This implies that chemical weathering rather than disproportionate physical removal of friable minerals is responsible for the compositional differences between rock and sediment. Mass balance analysis implies 3-10% of the sediment's mass is lost to solute dissolution, with approximately double that amount precipitated as clay minerals (a large portion of which may have been physically expelled). This result implies that temperate ice sheet subglacial environments may be more chemically active than previously realized. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

During the two decades following the first announcement of a tracking stock issue by General Motors in 1984, over 50 new tracking stocks were created. The value of a tracking stock is supposed to reflect the performance of a division or operation of a firm, but does not have a direct claim on the division's assets or income. The voting rights of the tracking stock are only for the parent corporation, with no direct voting rights for the tracked division. The claimed benefits of issuing tracking stock include the use of internal capital markets, additional disclosure of the firm's operations, reduction of agency costs, the ability to directly compensate divisional management on performance, and greater analyst following and liquidity. But the last new issue of a tracking stock took place in 2001. And few, if any, tracking stocks still trade. This study examines how and why tracking stocks have largely stopped being issued, and why so many have been dissolved either through exchanges of shares, or sales or spin-offs of the business units with tracking stock. [ABSTRACT FROM AUTHOR]

This article explores the motivation to change their defined benefit pension plan by either terminating the plan and replacing it with a defined contribution plan or converting it to a cash balance plan. Using Form 5500 data as well as firm financial data, we find firms wishing to change their defined benefit plans are motivated by potential wealth transfer and tax implications. Firms terminating pension plans tend to have lower potential wealth transfers and lower taxes than firms converting to a cash balance plan, indicating a desire to modify the implicit contract instead of terminating the plan. [ABSTRACT FROM AUTHOR]

This survey of approximately 70 studies considers five causes of weak financial system development in transition economies. These are: problem loans and inadequate capital; the absence of a credit culture, giving rise to perverse incentives to continue to make bad loans; inadequate regulatory systems; deposit insurance; and weak legal systems. There results a perverse feedback loop across the various problem areas that constrains the development of solutions. Policy recommendations include a focus on basic contract law as a way to break the perverse feedback loop. [ABSTRACT FROM AUTHOR]

The sensitivity of snowmelt-driven water supply to climate variability and change is difficult to assess in the mountain west, where strong climatic gradients coupled with complex topography are sampled by sparse ground measurements. We developed a model which ingests daily satellite imagery and meteorological data and is suitable for areas >1000 km2, yet captures spatial variability of snow accumulation and melt in steep mountain terrain. We applied the model for the years 2000-2008 to a 2900 km2 snowmelt-dominated watershed in NW Montana. We found that >25% of the basin's snow water equivalent (SWE) accumulates above the highest measurement station and >70% accumulates above the mean elevation of surrounding SNOTEL stations. Consequently, scaling point measurements of SWE to describe basin conditions could lead to significant misrepresentation of basin snow. Simulations imply that present-day temperature variability causes measures of snowmelt timing to vary by over 4 weeks from year-to-year. Temperature variability causes a larger spread in snowmelt timing in a warmer climate. On average, snowmelt timing occurs 3 weeks earlier in late 21st century projections, with about 25% of future conditions observed today. [ABSTRACT FROM AUTHOR]

The article presents the findings of the surveys collected throughout the five field seasons between 2002 and 2006 with regards to Bench Glacier in Alaska. The survey reveals a surface layer of radar transparent ice in the valley glacier which covers the upper half of ablation zone. It explains that this layer is defined by lack of radar scattering. It states this finding conclude that cold ice in polythermal glaciers can be identified through radar-transparent layers.

Monitoring the snow water equivalent (SWE) is critical to effective management of water resources in many parts of the world that depend on the mountain snowpack for water storage. There are currently no methods to remotely sense SWE with accuracy over large lateral distances in the steep and often forested terrain of mountain basins. Previous studies have shown that measurements of ground-penetrating radar (GPR) velocity can provide accurate estimates of SWE in dry snow. Introduction of liquid water into the snowpack results in a three-phase system that cannot be accurately characterized with GPR velocity alone. We show that measuring the frequency-dependent GPR signal attenuation and velocity provides a direct estimate of the complex dielectric permittivity. Because the imaginary component is a function only of liquid water content, we can utilize both the real and imaginary components of the permittivity to estimate liquid water content, snow density, and SWE using existing empirical relationships that are valid in the pendular regime. We tested this new method at two field sites and found that the estimates were accurate to within 12% of gravimetric methods in both a moist and a dry snowpack. GPR has the potential to provide SWE estimates across large lateral distances over a broad range of snow conditions. [ABSTRACT FROM AUTHOR]

Gorton and Winton (1998) link the size of the banking system in transition economies to financial stability. We provide empirical evidence consistent with their notion that the size of the financial system will be smaller in these countries. This effect holds even after controlling for the effect of rule of law and/or legal origin, and other relevant variables. Transition economy status, thus adds additional explanatory power to traditional law and finance explanations of financial development. Classification of transition economies by legal origin reveals that Russian legal origin has a strong negative effect on financial development. Regression analysis shows claims on the private sector/gross domestic product (GDP) to be 46 to 60 percentage points lower in the countries of the former Soviet Union, and 23 to 39 percentage points lower in non-Soviet transition economies compared to countries of English legal origin. There is a positive relation between claims on the private sector and the rule of law for a broad cross section of countries. [ABSTRACT FROM AUTHOR]

Tracking stock for a unit of a firm presumably allows the market to value and monitor that unit independently of the rest of the firm. Announcement of the creation of tracking stock elicits an abnormal share price response of 2.17% on average over a two-day period. The share price response at the time of the announcement is more favorable: when the voting rights of the tracking stock are based on a market valuation: when the parent company's debt ratio is relatively low: when the parent's previous stock performance is relatively poor; and when the parent is not engaging in an acquisition. These results are consistent with reduction of agency problems. At the same time, firms that create tracking stock do not experience higher long-term valuations, suggesting that agency problems are not resolved with the creation of tracking stock. [ABSTRACT FROM AUTHOR]

In this article I use a sample of 178 Czech firms that were in the first wave of voucher privatization to test changes in efficiency and profitability. Based on a previous study's methodology, nonparametric tests reveal that efficiency and profitability decreased immediately following privatization. This is in contrast to earlier studies that find privatization increases these measures. Changes in firms' operations do not vary significantly by size or ownership but do vary by industry type, with nonmanufacturing firms having more positive (or less negative) changes after privatization. Evidence indicates that in spite of the disappointing findings, positive operating performance changes are taking place, such as a decrease in employment. [ABSTRACT FROM AUTHOR]

This is a study of the determinants of share pricing and demand in the path-breaking Czech voucher-based multiple-round mass privatization auction. The results presented here document that share valuation and demand in this auction were based on firm characteristics such as return on sales, sales growth, and ownership structure in the early rounds. However, such information declined in importance while auction results on share prices and trading volumes from prior rounds increased in importance as determinants of share prices and demand in later rounds. While share prices overshot or undershot in the early rounds', by round four they had stabilized and the market cleared successfully by the fifth and final round. These results are new evidence on the price discovery process in the Czech privatization auction and confirm the success of this auction in the efficient pricing and equitable distribution of enterprise shares. [ABSTRACT FROM AUTHOR]