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Einstein@Home discovers first millisecond pulsar visible only in gamma rays
Source:  Einstein@Home
mercredi 28 février 2018 20:13

Einstein@Home has found two previously unknown rapidly rotating neutron stars in data from the Fermi gamma-ray space telescope. While all other such millisecond pulsars have also been observed with radio telescopes, one of the two discoveries is the first millisecond pulsar detectable solely through its pulsed gamma-ray emission.

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How do population dynamics affect impact of heat extremes?
Source:  Climateprediction.net
mardi 27 février 2018 16:59

Understanding how continuing increases in global mean temperature will exacerbate societal exposure to extreme weather events is a question of profound importance.

Following the signing of the Paris Agreement in December 2015, a targeted focus has emerged within the scientific community to better understand how changes to the global climate system will evolve in response to specific thresholds of future global mean warming, such as 1.5 ◦C or 2◦C above ‘pre-industrial levels’.

However, determining population exposure to the impacts of heat extremes at 1.5 °C and 2 °C of global warming requires not only a robust understanding of the physical climate system response, but also consideration of projected changes to overall population size, as well as where people will live in the future.

A recent analysis [1] by Dr Luke Harrington and Dr Friederike Otto of climateprediction.net introduces a new framework, adapted from studies of probabilistic event attribution, to disentangle the relative importance of regional climate emergence and changing population dynamics in the exposure to future heat extremes across multiple densely populated regions in Southern Asia and Eastern Africa (SAEA).

Their results reveal that, when population is kept at 2015 levels, exposure to heat considered severe in the present decade across these regions will increase by a factor of 4.1 (2.4–9.6) and 15.8 (5.0–135) under a 1.5°- and 2.0°-warmer world, respectively.

Projected population changes by the end of the century can further exacerbate these changes by a factor of 1.2 (1.0–1.3) and 1.5 (1.3–1.7), respectively. However, a large fraction of this additional risk increase is not related to absolute increases in population, but instead attributed to changes in which regions exhibit continued population growth into the future. Therefore continued African population expansion could place more people in locations where emergent changes to future heat extremes are exceptionally severe.

While local adaptation planners might be primarily be interested in how the patterns of heat extremes align with changes in population over their immediate community, it is equally important for decision makers to recognise the broader implications of heat exposure increases driven by future changes in where people live.

Acknowledgments

The authors would like to thank colleagues at the Oxford e-Research Centre: Andy Bowery, Sihan Li, Mamun Rashid, Sarah Sparrow and David Wallom for their technical expertise. They also acknowledge the MetOffice HadleyCentre PRECIS team for their technical and scientific support for the development and application of Weather@Home.

Finally, they would like to thank all of the volunteers who have donated their computing time to climateprediction.net andWeather@Home.

 

[1] Changing population dynamics and uneven temperature emergence combine to exacerbate regional exposure to heat extremes under 1.5°C and 2°C of warming, Environmental Research Letters, February 2018




ATLAS load tests
Source:  vLHCathome-dev
mardi 27 février 2018 16:49

For information: We have increased limits pr. host on the dev project as part of a campaign to test our new storage backend.

Expect most new ATLAS tasks to be pulled by our local cluster hosts and the LCG cluster in Bejing. But there are tasks for other applications too for those interested. There might be interruptions too, as this is our development and testbed. :-)


Flood project stakeholder workshop to take place in Dhaka, Bangladesh
Source:  Climateprediction.net
lundi 26 février 2018 14:40

Climateprediction.net’s Professor David Wallom and Dr Sarah Sparrow are visiting Dhaka, Bangladesh, this March for a stakeholder workshop around the REBuILD project (Risk Evaluation of Brahmaputra Inundations for Loss and Damage).

During this stakeholder workshop, participants will share their opinions and insights on how extreme event risk assessments could be further developed for comprehensive risk management, aiding Bangladesh policymakers in developing appropriate adaptation strategies for achieving Sustainable Development Goals.

Bangladesh is listed as one of the countries most vulnerable to climate change. It has one of the largest population densities in the world, resulting in high pressure on land and water resources. When an extreme weather event such as flooding occurs, millions of people are displaced and both freshwater supply and agricultural production are affected.

Understanding the impact of anthropogenic climate change and developing services to support government programmes such as the “Loss and Damage in Vulnerable Countries Initiative” within the country would be greatly beneficial.

The REBuILD project is a pilot study funded under the Global Challenges Research Fund (GCRF) involving a collaboration of researchers from the University of Oxford and Institute of Water and Flood Management (IWFM) of Bangladesh University of Engineering and Technology (BUET).

Using the unique computing infrastructure of climateprediction.net (CPDN), quantitative risk assessments are being carried out of the potential impacts of the Brahmaputra flooding during summer 2017.

Professor Wallom will open the workshop with an introduction to the climateprediction.net programme and its relevance to the REBuILD project. Dr Sparrow will present a case study of the analysis of the 2017 floods along with Khaled Mohammed of IWFM, who has been visiting the University to collaborate with Oxford researchers on the project over the past couple of months.

There will also be interactive sessions for all participants on the Brahmaputra Floods policy decisions and Exploring drivers and best practice in dealing with floods.

 




Gerasim@home:
Source:  Gerasim@home
lundi 26 février 2018 09:02

We have two new articles that are recently published in Open Engineering journal.

Vatutin E.I. Comparison of Decisions Quality of Heuristic Methods with Limited Depth-First Search Techniques in the Graph Shortest Path Problem // Open Engineering. Vol. 7. Iss. 1. 2017. pp. 428–434. DOI: 10.1515/eng-2017-0041. https://www.degruyter.com/view/j/eng.2017.7.issue-1/eng-2017-0041/eng-2017-0041.xml?format=INT

Vatutin E.I., Zaikin O.S., Kochemazov S.E., Valyaev S.Y. Using Volunteer Computing to Study Some Features of Diagonal Latin Squares // Open Engineering. Vol. 7. Iss. 1. 2017. pp. 453–460. DOI: 10.1515/eng-2017-0052. https://www.degruyter.com/view/j/eng.2017.7.issue-1/eng-2017-0052/eng-2017-0052.xml?format=INT

They are includes some results of computing experiments aimed to investigate quality of heuristic decisions in the graph shortest path problem (first) and to find diagonal Latin squares with extremal number of transversals (second).




Aliquot sequence 1157682 has terminated!!!
Source:  YAFU
jeudi 22 février 2018 09:45

Aliquot sequence 1157682 has terminated!!!




Scheduled Server Maintenance 2/21
Source:  Milkyway@home
mercredi 21 février 2018 16:15

Hi Everyone,

There will be a scheduled server outage today around 1pm. This should be a brief outage while we install some additional RAM in the server.

Thank you for your understanding.

Jake

***

The server has been upgraded. Let me know if you see any more database errors or other hiccups here.

***


The experimental QC for W10 is now called QC_beta
Source:  GPUGrid
mardi 20 février 2018 16:09

Another attempt... instructions here


Paper presents tool for assessing risk of hydro-meteorological extremes in UK
Source:  Climateprediction.net
lundi 19 février 2018 14:47

Extreme weather events such as droughts and heavy precipitation can have large impacts on society and the economy, so ensuring that society is well prepared to face such events will have multiple benefits.

Anthropogenic climate change is expected to have an impact on these types of events: warm temperature extremes and heavy precipitation extremes have been shown to have increased due to human greenhouse gas emissions and these are projected to increase in the future (IPCC, 2013).

Properly assessing the associated impacts and uncertainties is critical for adequate adaptation, however, the application of risk-based approaches often requires large sets of extreme events, which are not commonly available.

A new paper co-authored by climateprediction.net researchers presents just such a large set of hydro-meteorological time series for recent past and future conditions for the United Kingdom based on weather@home2, a modelling framework consisting of a global climate model driven by observed or projected sea surface temperature and sea ice which is downscaled to 25 km over the European domain by a regional climate model.

Future projections show small precipitation increases in winter but large decreases in summer on average, leading to an overall drying, consistent with the most recent UK Climate Projections (UKCP09) but larger in magnitude than the latter. Both drought and high-precipitation events are projected to increase in frequency and intensity in most regions, highlighting the need for appropriate adaptation measures.

Overall, the presented dataset is a useful tool for assessing the risk associated with drought and more generally with hydro-meteorological extremes in the UK.

 

A large set of potential past, present and future hydro-meteorological time series for the UK

Hydrology and Earth System Sciences, 25 Jan 2018

Benoit P. Guillod1,a,b, Richard G. Jones2,3, Simon J. Dadson3, Gemma Coxon4, Gianbattista Bussi3, James Freer4, Alison L. Kay5, Neil R. Massey1, Sarah N. Sparrow6, David C. H. Wallom6, Myles R. Allen1, and Jim W. Hall1

1 Environmental Change Institute, University of Oxford, Oxford, UK
Met Office Hadley Centre, Exeter, UK
School of Geography and the Environment, University of Oxford, Oxford, UK
Geographical Sciences, University of Bristol, Bristol, UK
Centre for Ecology and Hydrology, Wallingford, UK
Oxford e-Research Centre, University of Oxford, Oxford, UK
currently at: Institute for Environmental Decisions, ETH Zurich, Zurich, Switzerland
currently at: Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland




12-digit factor of P2203 has now been found by the project...
Source:  WEP-M+2 Project
lundi 19 février 2018 12:52

...141777 times - still no sign of any larger factors