Northern Eurasia Future Initiative (NEFI): facing the challenges and pathways of global change in the 21st century

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

Vegetation and climate changes on the northern Taymyr, Russia during the Upper Pleistocene and Holocene reconstructed from pollen records

Pollen data from a Levinson-Lessing Lake sediment core (74°28'N, 98°38'E) and Cape Sabler,Taymyr Lake permafrost sequences (74°33'N, 100°32'E) reveal substantial environmental changeson the northern Taymyr Peninsula during the last c. 32 000 14C years. The continuous recordsconfirm that a scarce steppe-like vegetation with Poaceae, Artemisia, and Cyperaceae dominatedc. 32 000-10 300 14C yr BP, while tundra-like vegetation with Oxyria, Ranunculaceae andCaryophyllaceae grew in wetter areas. The coldest interval occurred c. 18 000 yr BP. Lateglacialpollen data show several warming events followed by a climate deterioration c. 10 500 14C yr BP,which may correspond with the Younger Dryas. The Late Pleistocene/Holocene transition,c. 10 300-10 000 14C yr BP, is characterized by a change from the herb-dominated vegetation toshrubby tundra with Betula sect. Nanae and Salix. Alnus fruticosa arrived locally c. 9000-8500 14Cyr BP and disappeared c. 4000-3500 14C yr BP. Communities of Betula sect. Nanae, broadlydistributed at c. 10,000-3500 14C yr BP, almost disappeared when vegetation became similar tothe modern herb tundra after 3500-3000 14C yr BP. Quantitative climate reconstructions showLast Glacial Maximum summer temperature about 4°C below present and Preboreal (c. 10 00014C yr BP) temperature 2-4°C above present. Maximum summer temperature occurred between10 000 and 5500 14C yr BP; later summers were similar to present or slightly warmer