The extended dust emission around the nova GK persei

We have applied maximum entropy reconstruction methods to the IRAS observations of the nova GK Persei to examine the spatial distribution of the far-IR emission. We have discovered discrete regions of emission in a co-linear structure extending to 17 arcmin on either side of the binary system, supporting a stellar origin for the structure. We postulate that the evolved secondary is the progenitor of the circumbinary envelope.     

The Development of Seasonal and Inter-Annual Climate Forecasting

A review of the development and status of seasonal to inter-annual climate forecasting up until 2001 is presented covering not only the successes but also identifying some of the major challenges remaining. Included is discussion on the history of the enterprise; the scientific basis of modern seasonal to inter-annual prediction and its background of predictability theory; the current status of predictions and the measurement of their skill; the experiences and consequences of the 1997–1998 El Niño event; approaches to linking forecasts with applications; and a view to the future.     

The elementary universe

Mike Edmunds follows the trail of the elements in his George Darwin Lecture, given to the RAS on 10 December 2004.     

The short term climatic sensitivity of carbonate and silicate weathering fluxes: Insight from seasonal variations in river chemistry

Large seasonal variations in the dissolved load of the headwater tributaries of the Marsyandi river (Nepal Himalaya) for major cations and ⁸⁷Sr/⁸⁶Sr ratios are interpreted to result from a greater dissolution of carbonate relative to silicate at high runoff. There is up to a 0.003 decrease in strontium isotope ratios and a factor of 3 reduction in the Si(OH)₄/Ca ratio during the monsoon. These variations, in small rivers sampling uniform lithologies, result from a different response of carbonate and silicate mineral dissolution to climatic forcing. Similar trends are observed in compiled literature data, from both Indian and Nepalese Himalayan rivers. Carbonate weathering is more sensitive to monsoonal runoff because of its faster dissolution kinetics. Silicate weathering increases relative to carbonate during the dry season, and may be more predominant in groundwater with longer water-rock interaction times. Despite this kinetic effect, silicate weathering fluxes are dominated by the monsoon flux, when between 50% and 70% of total annual silicate weathering flux occurs.     

The Impact of Exotic Dune Grass Species on Foredune Development in Australia and New Zealand: a case study of Ammophila arenaria and Thinopyrum junceiforme

Marram grass (Ammophila arenaria) and sea-wheat grass (Thinopyrum junceiforme) have been introduced to Australia and New Zealand. This study examines the morphology of incipient foredunes and established foredunes associated with these species at two sites, Mason Bay in southern New Zealand, and the Younghusband Peninsula in South Australia. Both species invaded the existing foredunes very rapidly. In both cases the antecedent topography comprised relatively sparsely vegetated, irregular foredunes. Invasion resulted in continuous, regular, evenly vegetated foredunes. At Mason Bay a massive foredune has formed since 1958, in conjunction with Ammophila. Thinopyrum has formed an incipient foredune, with a ramp or terrace morphology, along the Younghusband Peninsula, South Australia. In both cases gaps in the former foredune have been closed and the indigenous foredune vegetation has been displaced. Both species may decrease the frequency and severity of blowout development. They are likely to be resilient to aeolian processes of sedimentation compared with dunes formed by indigenous species. Ammophila survives burial, is tolerant of drought and is resistant to erosion associated with storm surge and high waves. Thinopyrum is very tolerant of salinity. These species may adversely affect the long-term development of coastal barriers by inhibiting transgressive dune development.     

The XMM-Newton Serendipitous Sky Survey

Mike Watson heralds the 2XMM catalogue, a valuable new X-ray astronomy resource compiled from XMM-Newton observations.     

Shields for the starship Enterprise

Ruth Bamford, Robert Bingham and Mike Hapgood discuss the physics behind shielding spacecraft from solar and cosmic radiation with mini-magnetospheres.