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During the past several decades, the Earth system has changed significantly, especially across Northern Eurasia. Changes in the socio-economic conditions of the larger countries in the region have also resulted in a variety of regional environmental changes that can have global consequences. The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to better prepare societies for future developments. A key principle of NEFI is that these developments must now be secured through science-based strategies co-designed with regional decision-makers to lead their societies to prosperity in the face of environmental and institutional challenges. NEESPI scientific research, data, and models have created a solid knowledge base to support the NEFI program. This paper presents the NEFI research vision consensus based on that knowledge. It provides the reader with samples of recent accomplishments in regional studies and formulates new NEFI science questions. To address these questions, nine research foci are identified and their selections are briefly justified. These foci include warming of the Arctic; changing frequency, pattern, and intensity of extreme and inclement environmental conditions; retreat of the cryosphere; changes in terrestrial water cycles; changes in the biosphere; pressures on land use; changes in infrastructure; societal actions in response to environmental change; and quantification of Northern Eurasia’s role in the global Earth system. Powerful feedbacks between the Earth and human systems in Northern Eurasia (e.g., mega-fires, droughts, depletion of the cryosphere essential for water supply, retreat of sea ice) result from past and current human activities (e.g., large-scale water withdrawals, land use, and governance change) and potentially restrict or provide new opportunities for future human activities. Therefore, we propose that integrated assessment models are needed as the final stage of global change assessment. The overarching goal of this NEFI modeling effort will enable evaluation of economic decisions in response to changing environmental conditions and justification of mitigation and adaptation efforts.

The development of the El Nino-Southern Oscillation (ENSO) in 1997-98, the most intense in this century, has been monitored by space- and ground-based observations. In this study, the authors present the signatures of ENSO impacts on the surface-atmosphere system, as detected in satellite products that are routinely derived at NOAA from measurements by a single instrument on board NOAA polar-orbiting satellites - the Advanced Very High Resolution Radiometer (AVHRR). The Indonesian archipelago was selected to demonstrate how AVHRR products can be synergistically used to monitor interannual variability, such as caused by ENSO, on regional and global scales. The authors examined month-to-month changes in surface-atmosphere conditions over the region during July 1997-June 1998. The major ENSO impact over the Indonesian archipelago was a prolonged dry period with anomalously low amounts of cloud, precipitation, and water vapor. The net effect of these changes was a significant increase in the absorbed shortwave and outgoing longwave radiation fluxes. ENSO-induced drought coincided with the slash-and-burn agricultural season, which resulted in persistent fires and smoke from biomass burning, coveting larger areas, producing more smoke, remaining longer than during most dry seasons, and causing health hazards for millions of people in Southeast Asia. Analysis of the impact of fires on cloud microphysics confirms earlier suggestions that the effective cloud droplet size decreases due to smoke aerosols and cloud reflectivity increases due to higher concentration of small droplets. Analysis of areas with active fires showed a decrease in both surface albedo and fractional green vegetation as a result of intensive burning.

The reflectance of a W-[B.sub.4]C multilayer mirror, with a period thickness that increased with depth into the multilayer, was measured at near-normal incidence with synchrotron radiation and at grazing incidence with Cu K[Alpha] radiation. The period thickness increased linearly from 17.9 [Angstrom] at the top of the multilayer structure to 21.9 [Angstrom] at the substrate while the same ratio of nodal layer to period thickness was maintained. For a grazing angle of 80 [degrees] (10 [degrees] from normal incidence), the peak reflectance was 1.1% at a wavelength of 36 [Angstrom], and the reflectance profile was 1 [Angstrom] wide. For Cu K[Alpha] radiation the reflectance peaked at a grazing angle of 2.4 [degrees] and was 0.4 [degrees] wide. Compared with a W-[B.sub.4]C multilayer mirror with a constant period thickness, the depth-graded multilayer mirror has wider reflectance profiles at near-normal and grazing incidences, resulting in larger integrated reflectances and wider fields of view. Key words: X-ray optics, multilayer mirrors.

A study confirms a previous finding that angle-invariant retrievals cannot be obtained by any angle-independent coefficients in a linear sea surface temperature (SST) retrieval algorithm. Retrievals in the tropics can be improved by using new operational National Oceanic and Atmospheric Administration angle-dependent algorithms. A study is conducted in the tropical Atlantic on the use of empirical angular function approach for testing sea surface temperature satellite retrievals.

The measured normal-incidence reflectances of W/B4C multilayers mirrors are 2% in the 34-50-Angstrom wavelength region and are consistent with interfacial roughness in the range of 3-4 Angstrom.