Contrasting farmers' perception of climate change and climatic data: How (in)consistency supports risk reduction and resilience?

Farmers’ adaptation to climate change is a two-step process that involves perceiving stressors and identifying impacts to respond to variability and changes through specific actions and strategies. Hence, successful adaptation depends on how well changing climate is perceived, either from a ‘bottom-up’ pathway –where farmers observe and identify changes through past experience–, or by using a ‘top-down’ pathway –where changes are identified through climate records. A gap between both pathways tends to be related to farmers’ misperception. For example, as life experiences influence perception, farmers who have been directly affected by extreme climatic events tend to report that the probability of such event happening again is relatively high. Furthermore, as perception is in part a subjective phenomenon, therefore, different farmers in the same locality might construct different perceptions of climate change impacts even though they experience the same weather patterns. Consequently, increased attention has been put on combining the ‘civic science’ of farmers’ perceptions with the ‘formal science’ from meteorological reports to identify the (in)consistency between perceived and observed data and how this affect farmers’ resilience when facing climate change impacts. This contribution provides a review comparing farmers’ perception and climate observations to address a twofold research question: 1) Which extreme events and compound risks are perceived by farmers in contrast with observed data? And 2) How do past experiences and social-learning influence farmers’ resilience and their adaptive capacity? We analyze a portfolio of 147 articles collected from Scopus library catalogue since 2000. The bibliometrics analysis was coupled with the systematic review to 103 articles selected from the original portfolio. Comparison between perceived and observed changes were focus on what was changing (onset, duration or cessation regarding temperature and rainfall patterns) and how it was changing (amount, frequency, intensity or inter-annual variability). Results will be useful for managers, developers, and policymakers of climate adaptation strategies to be more in tune with farmers’ understandings of when and how weather is changing. Furthermore, the review could generate recommendations for the design, formulation, and implementation of adaptation policies that are better tailored to farmers’ perception at local conditions, being more efficient and conducive to risk analysis when facing climate change

Spectroscopy of the Lens Galaxy of Q0957+561A,B. Implications of a possible central massive dark object

We present new long-slit William Herschel Telescope spectroscopic observations of the lens galaxy G1 associated with the double-imaged QSO 0957+561A,B. The obtained central stellar velocity dispersion, sigma_l = 310 +/- 20 km/s, is in reasonable agreement with other measurements of this dynamical parameter. Using all updated measurements of the stellar velocity dispersion in the internal region of the galaxy (at angular separations < 1".5) and a simple isotropic model, we discuss the mass of a possible central massive dark object. It is found that the data of Falco et al. (1997) suggest the existence of an extremely massive object of (0.5-2.1) x 10E10/h M_\odot (80% confidence level), whereas the inclusion of very recent data (Tonry & Franx 1998, and this paper) substantially changes the results: the compact central mass must be $\le$ 6 x10E9/h M_\odot at the 90% confidence level. We note that, taking into account all the available dynamical data, a compact nucleus with a mass of 10E9/h M_\odot (best fit) cannot be ruled out.Comment: 20 pages, 10 figures ApJ, in pres

Cantilever-based electret energy harvesters

Integration of structures and functions allowed reducing electric consumptions of sensors, actuators and electronic devices. Therefore, it is now possible to imagine low-consumption devices able to harvest their energy in their surrounding environment. One way to proceed is to develop converters able to turn mechanical energy, such as vibrations, into electricity: this paper focuses on electrostatic converters using electrets. We develop an accurate analytical model of a simple but efficient cantilever-based electret energy harvester. Therefore, we prove that with vibrations of 0.1g (~1m/s^{2}), it is theoretically possible to harvest up to 30\muW per gram of mobile mass. This power corresponds to the maximum output power of a resonant energy harvester according to the model of William and Yates. Simulations results are validated by experimental measurements but the issues of parasitic capacitances get a large impact. Therefore, we 'only' managed to harvest 10\muW per gram of mobile mass, but according to our factor of merit, this puts us in the best results of the state of the art. http://iopscience.iop.org/0964-1726/20/10/105013Comment: This is an author-created, un-copyedited version of an article accepted for publication in Smart Materials and Structures. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The definitive publisher-authenticated version is available online at doi:10.1088/0964-1726/20/10/105013; http://iopscience.iop.org/0964-1726/20/10/10501

Recurrence of the blue wing enhancements in the high ionization lines of SDSS 1004+4112 A

We present integral field spectroscopic observations of the quadruple-lensed QSO SDSS 1004+4112 taken with the fiber system INTEGRAL at the William Herschel Telescope on 2004 January 19. In May 2003 a blueward enhancement in the high ionization lines of SDSS 1004+4112A was detected and then faded. Our observations are the first to note a second event of similar characteristics less than one year after. Although initially attributed to microlensing, the resemblance among the spectra of both events and the absence of microlensing-induced changes in the continuum of component A are puzzling. The lack of a convincing explanation under the microlensing or intrinsic variability hypotheses makes the observed enhancements particularly relevant, calling for close monitoring of this object.Comment: 4 pages, 5 figure