Farmer attitudes towards converting to organic farming

Despite the considerable interest in organic farming the Irish organic sector remains small. Therefore to target support for the sector it is important to understand why farmers make decisions in favour or against organic farming as well as to identify drivers and barriers affecting that decision. Adoption of organic farming is assumed to be driven by a variety of different reasons such as economic and socio-economic, structural and institutional factors (e.g. Defrancesco et al., 2008; Burton et al, 2003). However, information gathering (e.g. Genius et al, 2006) and attitudes of the farmer (e.g. Willock et al, 1999, Hattam, 2006, Rehman et al, 2007) are also important in that decision. This paper focuses on the role that the attitudes of farmers play in identifying drivers and barriers to the intention to convert to organic farming using the theory of planned behaviour. To set this paper in context, it is part of a larger study which aims to explain the decision to adopt or not to adopt organic farming over time with respect to a variety of factors such as economic, institutional and socio-economic as well as comparing the attitudes and objectives of organic and conventional farmers. The results presented here suggest that, under current circumstances, large-scale conversion to organic farming by drystock farmers within the next five years is uncertain, but nevertheless 6% of drystock farmers state considerable interest in going organic. It appears that farmers do not have strong opinions about organic farming but equally the results here suggest that they feel they do not have a good level of knowledge about organic farming. Therefore an increase in information mainly focused on promoting organic farming as a profitable alternative to conventional farming could have a positive impact on the tendency for conversion. Future conversion to organics is most likely to be financially driven, but nevertheless the farmers’ perception that only rich people can afford to buy organic food remains a barrier and considerations might be given towards approaches that might alter this mindset

Estimating Antarctic climate variability of the last millennium

Climate variability is determined by the climate system’s internal variability as well as its response to external forcing. A quantitative understanding of past Antarctic climate variability is therefore essential if we are to attribute and to detect anthropogenic influences on the current and future climate in Antarctica, and thus crucial for projecting the evolution of the Antarctic ice sheet. Analysis of stable water isotope data from ice cores in principle provides information on past temperature variability, but its quantitative interpretation is challenged by strong non-climate effects. So far, the magnitude and timescale dependency of both the climate signal and the noise in Antarctic isotope records remains largely unknown. Here, we present a new spectral method to separate climate signal and noise in a large collection of published and new annually-resolved ice core records from East Antarctic Dronning Maud Land and the West Antarctic Ice Sheet, spanning the last 200—1000 years. With this, we derive the first timescale-dependent estimate of Antarctic temperature variability and isotopic signal-to-noise ratio on decadal to centennial time scales. In contrast to the raw isotope data, we find a stronger increase in temperature variability on longer time scales, which is similar between the two study regions and to estimates from reanalysis and marine SST data. Spatial analysis of the estimated noise levels allows the separation of local stratigraphic noise from larger-scale noise due to precipitation intermittency. Signal-to-noise ratios only reach values above one for multi-centennial time scales. Our findings illustrate a consistent way of interpreting isotope records, but also highlight the remaining knowledge gaps in our understanding of Holocene climate and ice-core derived variability. We emphasize that our new method is applicable for distinguishing climate variability from local effects for any spatial, well-dated array of proxy temperature records

Reconciling Discrepancies between Uk37 and Mg/Ca Reconstructions of Holocene Marine Temperature Variability

Significant discrepancies exist between the detrended variability of late-Holocene marine temperatures inferred from Mg/Ca and Uk37 proxies, with the former showing substantially more centennial-scale variation than the latter. Discrepancies exceed that attributable to differences in location and persist across various calibrations, indicating that they are intrinsic to the proxy measurement. We demonstrate that these discrepancies can be reconciled using a statistical model that accounts for the effects of bioturbation, sampling and measurement noise, and aliasing of seasonal variability. The smaller number of individual samples incorporated into Mg/Ca measurements relative to Uk37 measurements leads to greater aliasing and generally accounts for the differences in the magnitude and distribution of variability. An inverse application of the statistical model is also developed and applied in order to estimate the spectrum of marine temperature variability after correcting for proxy distortions. The correction method is tested on surrogate data and shown to reliably estimate the spectrum of temperature variance when using high-resolution records. Applying this inverse method to the actual Mg/Ca and Uk37 data results in estimates of the spectrum of temperature variance that are consistent. This approach provides a basis by which to accurately estimate the distribution of intrinsic marine temperature variability from marine proxy records.Earth and Planetary Science