Introduction to the Circumpolar World: Module 1

This module introduces students to a course, called The Circumpolar World, and to the interdisciplinary study of this fascinating part of the globe. After a brief explanation of the six major learning objectives, the module goes on to describe the approach taken in the course, an approach that emphasizes that while the circumpolar north has often been viewed as a distant, exotic place, it can also be viewed more intimately, more familiarly. The module then introduces one of the course's key learning aids, a map of the region, and then defines some of the terms used to refer to the world's northernmost places. After covering some of the historical forces that have shaped the region and its peoples, the module concludes with a discussion of what interdisciplinary study is and why it is so important. Educational levels: High school, Undergraduate lower division

Geography and Physical Processes of the Circumpolar World

This module provides a brief introduction to the physical features and processes of the Arctic region and the significant factors that influence them, which include: the climate, including very low winter temperatures, relatively high summer temperatures, and the subsequent freeze-thaw cycle; the long-term glaciation cycle; and the presence or absence of water and the dynamics and influence thereof, both as liquid and ice, on the northern landscape. A review of map reading skills is also included. Educational levels: High school, Undergraduate lower division

A review of data on abundance, trends in abundance, habitat use and diet of ice-breeding seals in the Southern Ocean

The development of models of marine ecosystems in the Southern Ocean is becoming increasingly important as a means of understanding and managing impacts such as exploitation and climate change. Collating data from disparate sources, and understanding biases or uncertainties inherent in those data, are important first steps for improving ecosystem models. This review focuses on seals that breed in ice habitats of the Southern Ocean (i.e. crabeater seal, Lobodon carcinophaga; Ross seal, Ommatophoca rossii; leopard seal, Hydrurga leptonyx; and Weddell seal, Leptonychotes weddellii). Data on populations (abundance and trends in abundance), distribution and habitat use (movement, key habitat and environmental features) and foraging (diet) are summarised, and potential biases and uncertainties inherent in those data are identified and discussed. Spatial and temporal gaps in knowledge of the populations, habitats and diet of each species are also identified

Misc. Pub. 92-1

I submit herewith the annual report of the Agricultural and Forestry Experiment Station, School of Agriculture and Land Resources Management, University of Alaska Fairbanks, for the period ending December 31, 1991. This is done in accordance with an act of the Congress, approved M arch 2, 1887, entitled "An act to establish Agricultural Experiment Stations, in connection with the Agricultural Colleges established in the several states under the provisions of an act approved July 2,1862, and under the acts supplementary thereto," and also of the act of the Alaska Territorial Legislature, approved March 12,1935, accepting the provisions of the act of Congress. James V. Drew, DirectorStatement of Purpose -- Drastic Retreat of Columbia Glacier Shows Natural Reforestation at Work -- Reindeer Range and Productivity Studied in Beringia Heritage International Park -- Radio Collars Aid Research into Reindeer Calf Mortality -- Moose Browse on Site of Mining Reclamation Study -- Developing Marketing Strategies for Alaska's Agricultural Entrepreneurs -- R.S. 2477— The Key to Access Across Federal Lands -- Plant, Animal and Soil Sciences -- Forest Sciences -- Resources Management -- Grants and Funds -- Financial Statement -- Publications -- Staf

Transient simulations of the carbon and nitrogen dynamics in northern peatlands: from the Last Glacial Maximum to the 21st century

The development of northern high-latitude peatlands played an important role in the carbon (C) balance of the land biosphere since the Last Glacial Maximum (LGM). At present, carbon storage in northern peatlands is substantial and estimated to be 500 ± 100 Pg C (1 Pg C = 1015 g C). Here, we develop and apply a peatland module embedded in a dynamic global vegetation and land surface process model (LPX-Bern 1.0). The peatland module features a dynamic nitrogen cycle, a dynamic C transfer between peatland acrotelm (upper oxic layer) and catotelm (deep anoxic layer), hydrology- and temperature-dependent respiration rates, and peatland specific plant functional types. Nitrogen limitation down-regulates average modern net primary productivity over peatlands by about half. Decadal acrotelm-to-catotelm C fluxes vary between −20 and +50 g C m−2 yr−1 over the Holocene. Key model parameters are calibrated with reconstructed peat accumulation rates from peat-core data. The model reproduces the major features of the peat core data and of the observation-based modern circumpolar soil carbon distribution. Results from a set of simulations for possible evolutions of northern peat development and areal extent show that soil C stocks in modern peatlands increased by 365–550 Pg C since the LGM, of which 175–272 Pg C accumulated between 11 and 5 kyr BP. Furthermore, our simulations suggest a persistent C sequestration rate of 35–50 Pg C per 1000 yr in present-day peatlands under current climate conditions, and that this C sink could either sustain or turn towards a source by 2100 AD depending on climate trajectories as projected for different representative greenhouse gas concentration pathways

Biological Features and Processes of the Circumpolar World

This site considers the flora and fauna of the northern regions, which are unique because their environments are extreme and finely balanced. It looks at the major factors involved in the biological evolution of circumpolar ecosystems, such as cold temperatures and low precipitation, lack of solar energy during much of the year, a rich marine environment along an extended coastline, constant and ongoing changes in the northern environment, and the recent emergence of the region from the last ice age. The site suggests that in order to understand the living Arctic and Subarctic, we need to consider the fact that all living things are part of a system, depend on solar energy, and can thrive only in the presence of liquid water, and that the Arctic and Subarctic environments are comparatively new. Educational levels: High school, Undergraduate lower division

Soiling and other optical losses in solar-tracking PV plants in Navarra

Field data of soiling energy losses on PV plants are scarce. Furthermore, since dirt type and accumulation vary with the location characteristics (climate, surroundings, etc.), the available data on optical losses are, necessarily, site dependent. This paper presents field measurements of dirt energy losses (dust) and irradiance incidence angle losses along 2005 on a solar-tracking PV plant located south of Navarre (Spain). The paper proposes a method to calculate these losses based on the difference between irradiance measured by calibrated cells on several trackers of the PV plant and irradiance calculated from measurements by two pyranometers (one of them incorporating a shadow ring) regularly cleaned. The equivalent optical energy losses of an installation incorporating fixed horizontal modules at the same location have been calculated as well. The effect of dirt on both types of installations will accordingly be compared