Sökning: "areal"

Visar resultat 21 - 25 av 72 avhandlingar innehållade ordet areal.

  1. 21. Boreal Lake Sediments as Sources and Sinks of Carbon

    Författare :Cristian Gudasz; Tranvik Lars; David Bastviken; Susan Ziegler; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; boreal lakes; allochthonous; lake sediments; sediment mineralization; bacterial production; bacterial biomass; carbon cycle; Freshwater ecology; Limnisk ekologi; Limnologi; Limnology;

    Sammanfattning : Inland waters process large amounts of organic carbon, contributing to CO2 and CH4 emissions, as well as storing organic carbon (OC) over geological timescales. Recently, it has been shown that the magnitude of these processes is of global significance. LÄS MER

  3. 22. The role of biogeophysical feedbacks and their impacts in the arctic and boreal climate system

    Författare :Wenxin Zhang; Institutionen för naturgeografi och ekosystemvetenskap; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arctic and boreal vegetation change; Biogeophysical feedbacks; Albedo; Latent heat; Carbon budget; Representative concentration pathways; Eearth system model; LPJ-GUESS; RCA; Sea ice;

    Sammanfattning : The physical environment in the northern high latitudes including the Arctic cryosphere has undergone dramatic changes due to anthropogenic greenhouse gas warming, which since pre-industrial times has been twice or more the rate of global mean warming. Global climate models predict that this accelerated warming will continue for at least the next few decades. LÄS MER

  4. 23. Spatial variations of the urban climate and its influence on thermal comfort and behaviour

    Författare :Fredrik Lindberg; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sky view factor; air temperature; surface temperature; GIS; raster modelling; mean radiant temperature; globe temperature; the SOLWIEG-model; human behaviour; outdoor activity;

    Sammanfattning : The increased number of people living in urban areas emphasises the need for an improved understanding of how the urban climate affects human activity and behaviour. The spatial and temporal variation of climate within cities is an important factor in people’s health and well-being. LÄS MER

  5. 24. Optical Memories and Processing in Time- and Frequency Domain

    Författare :Baozhu Luo; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Optical storage; photon echo; spectral hole burning; nonlinear optics; fiber amplifier; logical operation; phase retrieval; polarization holographic recording and retrieval; optical processing; Atomic and molecular physics; Atom- och molekylärfysik; Fysicumarkivet A:1998:Luo;

    Sammanfattning : Spectral hole burning and photon echoes are the techniques for frequency-selective optical memories, which have the potential to increase areal data storage density by a factor 10**7. They also have the capability to perform in-memory data processing. LÄS MER

  7. 25. Patterns and Drivers of Regional Crop Production in Chad

    Författare :Erik Nilsson; Avdelningen för Teknisk vattenresurslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; agricultural systems; crop production; drivers; trend analysis; variability; regional analysis; Sahel;

    Sammanfattning : Agriculture constitutes the largest economic sector and professional occupation in Chad, and is undergoing rapid changes due to processes of population increase, institutional reforms, conflicts in neighbouring countries, increasingly globalized trade networks, and environmental changes. But despite their importance for livelihoods and economic growth, the specific patterns and drivers of change in the agricultural sector are however poorly understood. LÄS MER