Adapting the International System of Units to the twenty-first century

We review the proposal of the International Committee for Weights and Measures (Comité International des Poids et Mesures, CIPM), currently being considered by the General Conference on Weights and Measures (Conférences Générales des Poids et Mesures, CGPM), to revise the International System of Units (Le Système International d’Unitès, SI). The proposal includes new definitions for four of the seven base units of the SI, and a new form of words to present the definitions of all the units. The objective of the proposed changes is to adopt definitions referenced to constants of nature, taken in the widest sense, so that the definitions may be based on what are believed to be true invariants. In particular, whereas in the current SI the kilogram, ampere, kelvin and mole are linked to exact numerical values of the mass of the international prototype of the kilogram, the magnetic constant (permeability of vacuum), the triple-point temperature of water and the molar mass of carbon-12, respectively, in the new SI these units are linked to exact numerical values of the Planck constant, the elementary charge, the Boltzmann constant and the Avogadro constant, respectively. The new wording used expresses the definitions in a simple and unambiguous manner without the need for the distinction between base and derived units. The importance of relations among the fundamental constants to the definitions, and the importance of establishing a mise en pratique for the realization of each definition, are also discussed.

Pollination ecology in the 21st century: key questions for future research

To inspire new ideas in research on pollination ecology, we list the most important unanswered questions in the field. This list was drawn up by contacting 170 scientists from different areas of pollination ecology and asking them to contribute their opinion on the greatest knowledge gaps that need to be addressed. Almost 40% of them took part in our email poll and we received more than 650 questions and comments, which we classified into different categories representing various aspects of pollination research. The original questions were merged and synthesised, and a final vote and ranking led to the resultant list. The categories cover plant sexual reproduction, pollen and stigma biology, abiotic pollination, evolution of animal-mediated pollination, interactions of pollinators and floral antagonists, pollinator behaviour, taxonomy, plant-pollinator assemblages, geographical trends in diversity, drivers of pollinator loss, ecosystem services, management of pollination, and conservation issues such as the implementation of pollinator conservation. We focused on questions that were of a broad scope rather than case-specific; thus, addressing some questions may not be feasible within single research projects but constitute a general guide for future directions. With this compilation we hope to raise awareness of pollination-related topics not only among researchers but also among non-specialists including policy makers, funding agencies and the public at large.

Scripture, style and persuasion in seventeenth-century English theories of preaching

The distinction between a Puritan ‘plain’ and a Laudian ‘metaphysical’ preaching style rests on secular rhetorical theories of persuasion that are relatively unimportant to early Stuart homiletics but are central to later Latitudinarian polemics on preaching. Instead, the ‘English Reformed’ theory and method of sermon composition rests on the didactic function of preaching and the need for the Holy Spirit and hearers to co-operate with the preacher. Although Andrewes and some avant-garde conformists questioned this theory, they developed no alternative method of composition. Arguments made in the 1650s for direct inspiration by the Spirit contributed to the decline of both theory and method

Utopia and education in the seventeenth century: Bacon’s 'Salomon’s House' and its influence

New Worlds Reflected provides a significant contribution both to the history of utopian literature and travel, and to the wider cultural and intellectual history of the time, assembling original essays from scholars interested in representations of the globe and new and ideal worlds in the period from the sixteenth to eighteenth centuries, and in the imaginative reciprocal responsiveness of utopian and travel writing. Chapter 7 looks at the influence of Salomon’s House in Francis Bacon’s New Atlantis (1627) on later seventeenth-century educational utopias.

Beyond the American century: Walter Lippmann and American grand strategy, 1943-1950

As the United States became a world Power, journalist and intellectual Walter Lippmann feared that it would become its own worst enemy. During and after the Second World War, he tried to steer the country towards coherent statecraft, to define the national interest and the limits of power, and give geopolitical expression to the role of the United States as the core of an Atlantic strategic system. But in response to world war, the Truman Doctrine, and the Korean War, he became pessimistic about the country's ability to conduct strategy effectively. In the prophetic tradition, he believed that a fatal symbiosis between America's growing strength and domestic politics led it towards crisis. Though at times ahistorical, Lippmann's concept of strategy deserves attention for its dialogue between power and identity, for its questioning of “ends” as well as means, and for its focus on the danger of self-defeating behaviour.

Hydrological cycle in the Danube basin in present-day and XXII century simulations by IPCCAR4 global climate models

We present an intercomparison and verification analysis of 20 GCMs (Global Circulation Models) included in the 4th IPCC assessment report regarding their representation of the hydrological cycle on the Danube river basin for 1961–2000 and for the 2161–2200 SRESA1B scenario runs. The basin-scale properties of the hydrological cycle are computed by spatially integrating the precipitation, evaporation, and runoff fields using the Voronoi-Thiessen tessellation formalism. The span of the model- simulated mean annual water balances is of the same order of magnitude of the observed Danube discharge of the Delta; the true value is within the range simulated by the models. Some land components seem to have deficiencies since there are cases of violation of water conservation when annual means are considered. The overall performance and the degree of agreement of the GCMs are comparable to those of the RCMs (Regional Climate Models) analyzed in a previous work, in spite of the much higher resolution and common nesting of the RCMs. The reanalyses are shown to feature several inconsistencies and cannot be used as a verification benchmark for the hydrological cycle in the Danubian region. In the scenario runs, for basically all models the water balance decreases, whereas its interannual variability increases. Changes in the strength of the hydrological cycle are not consistent among models: it is confirmed that capturing the impact of climate change on the hydrological cycle is not an easy task over land areas. Moreover, in several cases we find that qualitatively different behaviors emerge among the models: the ensemble mean does not represent any sort of average model, and often it falls between the models’ clusters.

Manipulation and articulation: population statistics in 19th century France and England

The article presents an essay that deals with the study conducted by Donald MacKenzie and the case studies comparing the use of population statistics in France and Great Britain in the periods of 1825 and 1885. It analyzes Donald MacKenzie's study on the ways professional and political commitments informed the choice of statistical indexes in the British statistical community. Furthermore, the author is interested in knowing how this influenced the development of mathematical statistics in Great Britain. The author concludes that the differences in the debates over population statistics are accounted to the differences in the social and epistemological logics of population statistics.

A new parenthood paradigm for twenty-first century family law in England and Wales?

There are few other areas in family law where incongruence between the legal and social positions is as evident as that concerning parenthood. Recent cases involving lesbian couples and known sperm donors serve to highlight the increasing tension between the respective roles of biology, intention and functional parenting in the attribution of legal parental status. As both legislative and case-law developments have shown, intention is central in some circumstances, but not in others. The main claim of this paper is that this ad hoc approach leads to incoherent and unsatisfactory law: instead of striving to identify a status, what we are really looking to do is to identify the people who assume responsibility for a child. Drawing upon recent case-law, this paper explores how a conceptual reform of the law could result in a principled framework which would place formally recognised intention at the heart of parental status in order to reconnect legal duty with social reality for as many children and parents as possible. Moreover, it would ensure that parental status would not be dictated by the mode of conception of the child (natural or assisted). The analysis identifies the objectives of reform before proposing a new model which, while recognising the social importance of the biological parentage link, would reserve legal status for functional parenthood.

The impact of 21st century Arctic sea ice decline on the climate and mass balance of the Greenland ice sheet and Svalbard’s glaciers and ice caps

The Arctic is a region particularly susceptible to rapid climate change. General circulation models (GCMs) suggest a polar amplification of any global warming signal by a factor of about 1.5 due, in part, to sea ice feedbacks. The dramatic recent decline in multi-year sea ice cover lies outside the standard deviation of the CMIP3 ensemble GCM predictions. Sea ice acts as a barrier between cold air and warmer oceans during winter, as well as inhibiting evaporation from the ocean surface water during the summer. An ice free Arctic would likely have an altered hydrological cycle with more evaporation from the ocean surface leading to changes in precipitation distribution and amount. Using the U.K. Met Office Regional Climate Model (RCM), HadRM3, the atmospheric effects of the observed and projected reduction in Arctic sea ice are investigated. The RCM is driven by the atmospheric GCM HadAM3. Both models are forced with sea surface temperature and sea ice for the period 2061-2090 from the CMIP3 HadGEM1 experiments. Here we use an RCM at 50km resolution over the Arctic and 25km over Svalbard, which captures well the present-day pattern of precipitation and provides a detailed picture of the projected changes in the behaviour of the oceanic-atmosphere moisture fluxes and how they affect precipitation. These experiments show that the projected 21stCentury sea ice decline alone causes large impacts to the surface mass balance (SMB) on Svalbard. However Greenland’s SMB is not significantly affected by sea ice decline alone, but responds with a strongly negative shift in SMB when changes to SST are incorporated into the experiments. This is the first study to characterise the impact of changes in future sea ice to Arctic terrestrial cryosphere mass balance.

What influence will future solar activity changes over the 21st century have on projected global near-surface temperature changes?

During the 20th century, solar activity increased in magnitude to a so-called grand maximum. It is probable that this high level of solar activity is at or near its end. It is of great interest whether any future reduction in solar activity could have a significant impact on climate that could partially offset the projected anthropogenic warming. Observations and reconstructions of solar activity over the last 9000 years are used as a constraint on possible future variations to produce probability distributions of total solar irradiance over the next 100 years. Using this information, with a simple climate model, we present results of the potential implications for future projections of climate on decadal to multidecadal timescales. Using one of the most recent reconstructions of historic total solar irradiance, the likely reduction in the warming by 2100 is found to be between 0.06 and 0.1 K, a very small fraction of the projected anthropogenic warming. However, if past total solar irradiance variations are larger and climate models substantially underestimate the response to solar variations, then there is a potential for a reduction in solar activity to mitigate a small proportion of the future warming, a scenario we cannot totally rule out. While the Sun is not expected to provide substantial delays in the time to reach critical temperature thresholds, any small delays it might provide are likely to be greater for lower anthropogenic emissions scenarios than for higher-emissions scenarios.