Interpreting the nature of Northern and Southern Annular Mode variability in CMIP5 Models
Abstract:
Characteristic timescales for the Northern Annular Mode (NAM) and Southern Annular Mode (SAM) variability are diagnosed in historical simulations submitted to the Coupled Model Intercomparison Project Phase 5 (CMIP5) and are compared to the European Centre for Medium-Range Weather Forecasts ERA-Interim data. These timescales are calculated from geopotential height anomaly spectra using a recently developed method, where spectra are divided into low-frequency (Lorentzian) and high-frequency (exponential) parts to account for stochastic and chaotic behaviors, respectively. As found for reanalysis data, model spectra at high frequencies are consistent with low-order chaotic behavior, in contrast to an AR1 process at low frequencies. This places the characterization of the annular mode timescales in a more dynamical rather than purely stochastic context. The characteristic high-frequency timescales for the NAM and SAM derived from the model spectra at high frequencies are ∼5 days, independent of season, which is consistent with the timescales of ERA-Interim. In the low-frequency domain, however, models are slightly biased toward too long timescales, but within the error bars, a finding which is consistent with previous studies of CMIP3 models. For the SAM, low-frequency timescales in November, December, January, and February are overestimated in the models compared to ERA-Interim. In some models, the overestimation in the SAM austral summer timescale is partly due to interannual variability, which can inflate these timescales by up to ∼40% in the models but only accounts for about 5% in the ERA-Interim reanalysis.Top ten research priorities for spinal cord injury: the methodology and results of a British priority setting partnership.
Abstract:
Study design
This is a mixed-method consensus development project.
Objectives
The objective of this study was to identify a top ten list of priorities for future research into spinal cord injury (SCI).
Setting
The British Spinal Cord Injury Priority Setting Partnership was established in 2013 and completed in 2014. Stakeholders included consumer organisations, healthcare professional societies and caregivers.
Methods
This partnership involved the following four key stages: (i) gathering of research questions, (ii) checking of existing research evidence, (iii) interim prioritisation and (iv) afinal consensus meeting to reach agreement on the top ten research priorities. Adult individuals with spinal cord dysfunction because of trauma or non-traumatic causes, including transverse myelitis, and individuals with a cauda equina syndrome (henceforth grouped and referred to as SCI) were invited to participate in this priority setting partnership.
Results
We collected 784 questions from 403 survey respondents (290 individuals with SCI), which, after merging duplicate questions and checking systematic reviews for evidence, were reduced to 109 unique unanswered research questions. A total of 293 people (211 individuals with SCI) participated in the interim prioritisation process, leading to the identification of 25 priorities. At a final consensus meeting, a representative group of individuals with SCI, caregivers and health professionals agreed on their top ten research priorities.
Conclusion
Following a comprehensive, rigorous and inclusive process, with participation from individuals with SCI, caregivers and health professionals, the SCI research agenda has been defined by people to whom it matters most and should inform the scope and future activities of funders and researchers for the years to come.