Observations using the Bent Crystal Spectrometer instrument on the Solar Maximum Mission show that turbulence and blue-shifted motions are characteristic ofthe soft X-ray plasma during the impulsive phase &flares, and are coincident with the hard X-ray bursts observed by the Hard X-ray Burst Spectrometer. A method for analysing the Ca xIx and Fe xxv spectra characteristic of the impulsive phase is presented. Non-thermal widths and blue-shifted components in the spectral lines of Ca xlx and Fe xxv indicate the presence of turbulent velocities exceeding 100 km s ~ and upward motions of 300-400 km s ~.The April 10, May 9, and June 29, 1980 flares are studied. Detailed study of the geometry of the region, inferred from the Flat Crystal Spectrometer measurements and the image of the flare detected by the Hard X-ray Imaging Spectrometer, shows that the April 10 flare has two separated footpoints bright in hard X-rays. Plasma heated to temperatures greater than 107 K rises from the footpoints. During the three minutes in which the evaporation process occurs an energy of 3.7 x 1030 ergs is deposited in the loop. At the end of the evaporation process, the total energy observed in the loop reaches its maximum value of 3 x 1030 ergs. This is consistent with the above figures, allowing for loss by radiation and conduction. Thus the energy input due to the blue-shifted plasma flowing into the flaring loop through the footpoints can account for the thermal and turbulent energy accumulated in this region during the impulsive phase.

Abstract. The Cassini RADAR instrument is a multimode 13.8 GHz multiple-beam sensor that can operate as a synthetic-aperture radar (SAR) imager, altimeter, scatterometer, and radiometer. The principal objective of the RADAR is to map the surface of Titan. This will be done in the imaging, scatterometer, and radiometer modes. The RADAR altimeter data will provide information on relative elevations in selected areas. Surfaces of the Saturn's icy satellites will be explored utilizing the RADAR radiometer and scatterometer modes. Saturn's atmosphere and rings will be probed in the radiometer mode only. The instrument is a joint development by JPL/NASA and ASI. The RADAR design features significant autonomy and data compression capabilities. It is expected that the instrument will detect surfaces with backscatter coefficient as low as −40 dB.

SIR-We propose a way to stimulate the Earth's capacity to cure itself, as an emergency treatment for the pathology of global warming. Measurements of the climate system show that the Earth is fast becoming a hotter planet than anything yet experienced by humans. Processes that would normally regulate climate are being driven to amplify warming. Such feedbacks, as well as the inertia of the Earth system-and that of our responsemake it doubtful that any of the wellintentioned technical or social schemes for carbon dieting will restore the status quo. What is needed is a fundamental cure. The oceans, which cover more than 70% of the Earth's surface, are a promising place to seek a regulating influence. One approach would be to use free-floating or tethered vertical pipes to increase the mixing of nutrient-rich waters below the thermocline with the relatively barren waters at the ocean surface. (We acknowledge advice from Armand Neukermans on engineering aspects of the pipes.) Water pumped up pipes-say, 100 to 200 metres long, 10 metres in diameter and with a one-way flap valve at the lower end for pumping by wave movementwould fertilize algae in the surface waters and encourage them to bloom. This would pump down carbon dioxide and produce dimethyl sulphide, the precursor of nuclei that form sunlight-reflecting clouds. Such an approach may fail, perhaps on engineering or economic grounds. And the impact on ocean acidification will need to be taken into account. But the stakes are so high that we put forward the general concept of using the Earth system's own energy for amelioration. The removal of 500 gigatonnes of carbon dioxide from the air by human endeavour is beyond our current technological capability. If we can't 'heal the planet' directly, we may be able to help the planet heal itself.

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The aims of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) are to provide a framework for the intercomparison of global and regional-scale risk models within and across multiple sectors and to enable coordinated multi-sectoral assessments of different risks and their aggregated effects. The overarching goal is to use the knowledge gained to support adaptation and mitigation decisions that require regional or global perspectives within the context of facilitating transformations to enable sustainable development, despite inevitable climate shifts and disruptions. ISIMIP uses community-agreed sets of scenarios with standardized climate variables and socioeconomic projections as inputs for projecting future risks and associated uncertainties, within and across sectors. The results are consistent multi-model assessments of sectoral risks and opportunities that enable studies that integrate across sectors, providing support for implementation of the Paris Agreement under the United Nations Framework Convention on Climate Change.