A review of the uncertainties in estimates of global oil resources

This paper discusses the uncertainties that exist in estimating the remaining ultimately recoverable resources of oil globally including the reasons for these and, where possible, how they may be mitigated, resolved, or reduced in future assessments. The encompassing and ambiguous terms ‘conventional oil’ and ‘unconventional oil’ are disaggregated into the numerous categories of oil that exist within each. These categories are investigated individually in order to identify the specific uncertainties by which they are influenced and affected. A key finding is that there are intrinsic uncertainties within every category of oil. Future assessments of global oil resources and projections of oil production should hence acknowledge these issues, explain or assess the effects that they have on results, and present ranges in any estimates produced or provided. An initial estimate is made of the technically recoverable resources of the light tight oil often called ‘shale oil’: oil found in low permeability shale formations requiring stimulation to be extracted. These resources are estimated to range on a global scale between 150 and 508 billion barrels with a central estimate of 278 billion barrels

Uncertainties in the outlook for oil and gas

Oil and gas will play a central role in the global energy system for the foreseeable future. However, uncertainty surrounds both the availability of and demand for these fuels, and as a result, there are quite disparate viewpoints on the magnitude of this role. The aim of this thesis is to identify, understand, quantify and, where possible, minimise the sources of this uncertainty, and to investigate the implications that such uncertainties have on the future of oil and gas. There are two areas of original contribution to knowledge. First, while numerous studies have examined the availability of various subsets of oil and gas, often in a deterministic manner, this work provides a full description of the uncertainty in the resource potential of all individual categories of oil and gas. This includes estimating the uncertainty in resource availability at different costs of production, and also examining the resource potential of categories that have been previously overlooked. Second, the implications of this and other major sources of uncertainty have never been investigated using models that incorporate both supply and demand-side dynamics. Two models are used for this purpose. The first is an existing energy systems model, TIAM-UCL, which has been substantially modified to allow a more accurate characterisation of long-term oil and gas production and consumption. The second is an oil-sector specific model that has been developed named the 'Bottom-Up Geological and Economic Oil field production model' (BUEGO). This is capable of examining oil production potential to 2035 and is used to examine shorter-term and more sector specific uncertainties

Gene expression profiling of monkeypox virus-infected cells reveals novel interfaces for host-virus interactions

Monkeypox virus (MPV) is a zoonotic Orthopoxvirus and a potential biothreat agent that causes human disease with varying morbidity and mortality. Members of the Orthopoxvirus genus have been shown to suppress antiviral cell defenses, exploit host cell machinery, and delay infection-induced cell death. However, a comprehensive study of all host genes and virus-targeted host networks during infection is lacking. To better understand viral strategies adopted in manipulating routine host biology on global scale, we investigated the effect of MPV infection on Macaca mulatta kidney epithelial cells (MK2) using GeneChip rhesus macaque genome microarrays. Functional analysis of genes differentially expressed at 3 and 7 hours post infection showed distinctive regulation of canonical pathways and networks. While the majority of modulated histone-encoding genes exhibited sharp copy number increases, many of its transcription regulators were substantially suppressed; suggesting involvement of unknown viral factors in host histone expression. In agreement with known viral dependence on actin in motility, egress, and infection of adjacent cells, our results showed extensive regulation of genes usually involved in controlling actin expression dynamics. Similarly, a substantial ratio of genes contributing to cell cycle checkpoints exhibited concerted regulation that favors cell cycle progression in G1, S, G2 phases, but arrest cells in G2 phase and inhibits entry into mitosis. Moreover, the data showed that large number of infection-regulated genes is involved in molecular mechanisms characteristic of cancer canonical pathways. Interestingly, ten ion channels and transporters showed progressive suppression during the course of infection. Although the outcome of this unusual channel expression on cell osmotic homeostasis remains unknown, instability of cell osmotic balance and membrane potential has been implicated in intracellular pathogens egress. Our results highlight the role of histones, actin, cell cycle regulators, and ion channels in MPV infection, and propose these host functions as attractive research focal points in identifying novel drug intervention sites

Persistent Place-Making in Prehistory: the Creation, Maintenance, and Transformation of an Epipalaeolithic Landscape

Most archaeological projects today integrate, at least to some degree, how past people engaged with their surroundings, including both how they strategized resource use, organized technological production, or scheduled movements within a physical environment, as well as how they constructed cosmologies around or created symbolic connections to places in the landscape. However, there are a multitude of ways in which archaeologists approach the creation, maintenance, and transformation of human-landscape interrelationships. This paper explores some of these approaches for reconstructing the Epipalaeolithic (ca. 23,000–11,500 years BP) landscape of Southwest Asia, using macro- and microscale geoarchaeological approaches to examine how everyday practices leave traces of human-landscape interactions in northern and eastern Jordan. The case studies presented here demonstrate that these Epipalaeolithic groups engaged in complex and far-reaching social landscapes. Examination of the Early and Middle Epipalaeolithic (EP) highlights that the notion of “Neolithization” is somewhat misleading as many of the features we use to define this transition were already well-established patterns of behavior by the Neolithic. Instead, these features and practices were enacted within a hunter-gatherer world and worldview

The geographical distribution of fossil fuels unused when limiting global warming to 2 °C

Policy makers have generally agreed that the average global temperature rise caused by greenhouse gas emissions should not exceed 2 °C above the average global temperature of pre-industrial times. It has been estimated that to have at least a 50 per cent chance of keeping warming below 2 °C throughout the twenty-first century, the cumulative carbon emissions between 2011 and 2050 need to be limited to around 1,100 gigatonnes of carbon dioxide (Gt CO2). However, the greenhouse gas emissions contained in present estimates of global fossil fuel reserves are around three times higher than this, and so the unabated use of all current fossil fuel reserves is incompatible with a warming limit of 2 °C. Here we use a single integrated assessment model that contains estimates of the quantities, locations and nature of the world's oil, gas and coal reserves and resources, and which is shown to be consistent with a wide variety of modelling approaches with different assumptions, to explore the implications of this emissions limit for fossil fuel production in different regions. Our results suggest that, globally, a third of oil reserves, half of gas reserves and over 80 per cent of current coal reserves should remain unused from 2010 to 2050 in order to meet the target of 2 °C. We show that development of resources in the Arctic and any increase in unconventional oil production are incommensurate with efforts to limit average global warming to 2 °C. Our results show that policy makers' instincts to exploit rapidly and completely their territorial fossil fuels are, in aggregate, inconsistent with their commitments to this temperature limit. Implementation of this policy commitment would also render unnecessary continued substantial expenditure on fossil fuel exploration, because any new discoveries could not lead to increased aggregate production