• Encyclopedia of Geology
  Articles concerning the theory and application of geology.
• Encyclopedia of Quaternary Science
  The history of the earth, from the ice age til today.
• Encyclopedia of Global Warming and Climate Change, 2008
  Thematically covers the social and scientific aspects of climate change, and the history and controversies thereby.
• Encyclopedia of Ocean Sciences
  Around 400 articles that cover the biological, chemical and physical aspects of the oceans.
• Encyclopedia of Soils in the Environment
  Multidisciplinary and comprehensive work about the science of the Earth.
• Treatise on Geochemistry
  Deals with all major fields within Geochemistry.
• Den Store Danske
  (In Danish) The Great Danish: This Encyclopedia is the biggest general Danish lexicon, but has a lot of articles specifically about Danish circumstances (history, literature, culture and society).

• Lyell Collection
  Large database launched in 2007, containing many publications and journals from The Geological Society of London.
• GeoRef
  GeoRef covers North American geology from 1693 to present day and geology in the rest of the world from 1933 to present day. The Database contains references to all publications from the US Geological Survey. Masters theses and Ph.D. dissertations from American and Canadian universities are also included.
• Tidsskrift.dk
  (In Danish, option to switch to English) Journal database with selected Danish journals. Some from as far back as the 1800 hundreds. The journals cover history, geography, biology, economy, politics, music and more.
• Norart
  Norart gives access to full-length articles and references to articles in Norwegian and Nordic scientific journals and yearbooks.
• DOAJ (Directory of Open Access Journals)
  (Open Access) Journal database with freely available scientific journals in full length.
• Sage Publications
  Journal database with scientific, peer-reviewed journals in the fields of Social Science, the Humanities, Natural Science and Technical Science.
• WoS (Web of science)
  Web of Science (WoS) is an article-base and a citation-index, with references to articles in all fields.
• Scopus
  Scopus is both an article-base and a citation-index. Scopus indexes more journals than any other base, and the thorough indexing and treatment of cited articles makes Scopus a good alternative to more field-specific databases. Scopus covers Medical Science, Natural Science, Social Science and increasingly the Humanities (especially European Humanities and Medical Anthropology)
• Article search in Bibliotek.dk
  (In Danish, option to switch to English) 1945- Danish database (Bibliotek.dk) with articles from newspapers, journals, and the internet. You now have the option to order copies from around 30.000 journals from Det Kgl. Bibliotek through bibliotek.dk.
  These articles will be sent as electronic copies to your mailbox within minutes – or one to two workdays if the articles have yet to be scanned.
  A few articles are not free. Danish articles from newspapers and other media are free through Infomedia.
• Infomedia
  Denmark’s biggest database with more than 14 million searchable full-length articles from 200 Danish media.
  Click on “Search” to gain access. Many of the articles are now shown in PDF-format, for instance as a copy of the actual newspaper site.

• DGF (English) - Bulletin of the Geological Society of Denmark
  Themes in this Journal: All fields of geological sciences, with a focus on works from Denmark, The Faroes and Greenland. (Open Access)
• Elements
  Themes in this Journal: Mineralogy, Geochemistry and Petrology. (Open Access)
• Aktuel Naturvidenskab
  (In Danish) News and background form the world of Natural Science. (Open Access)
• Geoviden - Geologi og Geografi
  (In Danish) Popular Science magazine focused towards teachers in geology and geography, and others who have an interest in these fields. (Open Access)
• Geoscientist Online
  Fellowship magazine of the Geological Society of London.
• GEUS: Journals
  Scientific journals published by the Geological Survey of Denmark and Greenland
• GSA Today (Geological Society of America)
  Journals goal is to inform members of the GSA about news in science. (Open Access)
• Polarfronten
  (In Danish) Themes in this Journal: Polar research – initiatives, expeditions and daily work. (Open Access)
• Norsk sokkel
  (In Norwegian, option to switch to English) An Open Access journal published by the Norwegian Petroleum directorate. (Open Access)
• AGU: Journal of Geophysical Research: Atmospheres
  Themes in this Journal: Atmospheric properties, atmospheric processes, the atmosphere and its interaction with the Earth.
• AGU: Journal of Geophysical Research: Biogeosciences
  Themes in this Journal: biogeochemistry, biogeophysics, atmosphere-, land-, and ocean-ecosystem interactions, biomineralization, life in extreme environments, astrobiology, microbial processes, geomicrobiology, and evolutionary geobiology.
• AGU: Journal of Geophysical Research: Earth Surface
  Themes in this Journal: fluvial, eolian, and coastal sediment transport; hillslope mass movements; glacial and periglacial activity; weathering and pedogenesis; and surface manifestations of volcanism and tectonism.
• AGU: Journal of Geophysical Research: Oceans
  Themes in this Journal: physics, chemistry, biology, and geology in the study of the oceans.
• AGU: Journal of Geophysical Research: Planets
  Themes in this Journal: planetary geology, geophysics, geochemistry, atmospheres, and dynamics.
• AGU: Journal of Geophysical Research: Solid Earth
  Themes in this Journal: Solid Earth, liquid core, geomagnetism, paleomagnetism, marine geology/geophysics, chemistry, physics of minerals, rocks, volcanology, seismology, geodesy, gravity, and tectonophysics.
• AGU: Journal of Geophysical Research: Space Physics
  Themes in this Journal:  aeronomy, magnetospheric physics, planetary atmospheres, ionospheres, magnetospheres, solar and interplanetary physics, cosmic rays, and heliospheric physics.
• AGU: Reviews of Geophysics
  Themes in this Journal:  overviews and syntheses of recent research in all areas of the Earth and space sciences.
• AGU: G3 - Geochemistry, Geophysics, Geosystems
  Themes in this Journal: Solid Earth, hydrosphere, atmosphere, biosphere, and solar system. The Earth as a system.
• AGU: Geophysical Research Letters
  Themes in this Journal: communications-length articles within all the major geoscience disciplines.
• AGU: Global Biogeochemical Cycles
  Themes in this Journal: regional and global biogeochemical interactions, biogeochemical processing, physical Earth Systems, climate.
• AGU: JAMES - Journal of Advances in Modeling Earth Systems
  Themes in this Journal: climate science, atmospheric and oceanic circulations, radiation, cloud physics, boundary layer, and land surface processes, the biosphere and cryosphere, biogeochemical cycles,  model parameterizations, Earth systems modeling.
• AGU: Paleoceanography and Paleoclimatology
  Themes in this Journal: Earth’s past climate, paleoceanography, marine and terrestrial records.
• AGU: Tectonics
  Themes in this Journal: evolution, structure, and deformation of Earth¹s lithosphere, petrological, geochemical, geochronological, geophysical, remote-sensing, and modeling studies.
• AGU: Water Resources Research
  Themes in this Journal:  the role of water in the physical, chemical, biological, and ecological sciences. Public health and related social and policy sciences.
• AGU: Earth's Future
  Themes in this Journal: global change, sustainability and resiliency. (Open Access)
• AGU: Earth and Space Science
  Themes in this Journal: Earth, planetary, and space sciences. Environmental science, geo- and space-engineering, and biogeochemistry. (Open Access)
• AGU: Eos Transactions

• Geology.com
  Geology and Earth Science Terms and Definitions
• Glossary of Glacier Terminology
  A glossary providing the vocabulary necessary to understand the modern glacier environment.
• Den Danske Ordbog
  (In Danish) The Danish Dictionary is the most comprehensive dictionary over the modern Danish language. It provides information about the spelling, form, pronunciation, origin, meaning and use of Danish words. The Dictionary is corpus based, meaning that it largely reflects the language as it is spoken and written by the language users. Updates frequently.
• ODS - Ordbog over det danske Sprog
  (In Danish) The Dictionary over the Danish language is the largest Dictionary over the Danish language. With its around 250.000 words and expressions from 1700 to 1950, the work is of interest to all who wish to know the origins, development and use of the Danish language.
• Retskrivningsordbogen
  (In Danish) In the Retskrivningsordbog (Correct-way-to-write dictionary) online you can search both from the beginning of words and towards the end of Danish words. For instance if you search for the word “Penge” (Money) in the start of that word you will get words that in Danish has that word at the start: Penge (Money), Pengeafpresning (Blackmail), Pengeafpresser (Blackmailer) and so on.
  If you search towards the end of the word, you will get words that end on the word: Bompenge (Toll), Bropenge (Bridge toll), Byttepenge (change) and so on. 
• Sproget.dk
  (In Danish) This portals intention is to increase the visibility and to spread knowledge about the Danish language. Primarily focused towards language users who work professionally with communication in Danish (Proofreaders, Journalists, information workers).
• Ordbogen.com
  (In Danish) Collection of dictionaries which contains Ordbogen.com and Gyldendals Ordbøger. The collection of dictionaries covers a large number of subject areas and languages. The list of all relevant dictionaries is obtained when you search a word. Updates frequently with words, which users do not find in the first attempt. Also contains the most used words and expressions within certain languages (English, German, French…). Comments on translations and has information about word classes, inflections, categories, synonyms and proverbs.

• Klimatilpasningsværktøjet KAMP (Danmark)
  The map shows what different degrees of impact by sea rise and extreme rain will have on the Danish landscape.
• Kystplanlæggeren (Danmark)
  Nationwide mapping of the risk in coastal areas of Denmark until 2120.
• GEUS Data og Kort (Danmark)
  GEUS' (De Nationale Geologiske Undersøgelser for Danmark og Grønland) Publicly available Danish and Greenlandic map data.

• ASTER Global Digital Elevation Map
  Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). Global Digital Elevation Map.

• Map Collection
  World Sites Atlas features maps of world regions, countries, states, and cities.

• Geology.com
  Satellite images of countries, states, U.S. cities and world cities.

• Miljøgis (Danmark)
  (In Danish) The Ministry of Environments and Food of Denmark’s maps of Denmark. Option to divide Denmark into sections around certain parameters.

• Styrelsen for Dataforsyning og Infrastruktur (Danmark)
  (In Danish) Different kinds of geodata-maps of Denmark and Greenland. 

• Geodatastyrelsen, Matrikel og Søkort
  The Danish Geodata Agency. Recording real estate in Denmark and nautical charts in Denmark, Greenland and the Faroe Islands. 

• IHME1500 - International Hydrogeological Map of Europe
  Series of general hydrogeological maps comprising 25 map sheets, partly with explanatory notes, covering nearly the whole European continent and parts of the Near East.

• GEUS: Subsurface Maps of Denmark
  GEUS (De Nationale Geologiske Undersøgelser for Danmark og Grønland) Maps of Denmark. 

• DigDag
  (In Danish) Digital atlas of Denmark’s historical-administrative geography. 

• Statsbibliotekets Kort og Billedsamling
  (In Danish) The map and picture collection of the State Library, with it’s around 460.000 units, is together with the older and bigger collection in the Royal Library unique and of national, cultural and scientific significance.  

• Digitale kort i Det Kongelige Bibliotek
  (In Danish) Geographical maps, city maps, prospectuses and more from the Royal Library’s map collection. 

• Kartverket (Norge)
  Maps and geographical information about Norway.

• Lantmäteriets kortbutik (Sverige)
  (In Swedish) Maps of Sweden. 

• Nordisk Korthandel
  (In Danish) Business selling maps of different kinds from selected countries and areas.

• Wikimapia
  User driven satellite map project, in which the users themselves describe the different areas and landmarks.  

• Google Maps

• Google Earth 

• CLEAN - Climate Literacy and Energy Awareness Network (Internationalt)
  CLEAN's primary effort is to steward the collection of climate and energy science educational resources and to support a community of professionals committed to improving climate and energy literacy.

• IPCC - Intergovernmental Panel on Climate Change (Internationalt)
  The IPCC reviews and assesses the most recent scientific, technical and socio-economic information produced worldwide relevant to the understanding of climate change. It does not conduct any research nor does it monitor climate related data or parameters.

• Nordic Volcanological Center (Internationalt)
  The Nordic Volcanological Center (NordVulk) is a nordic research center specializing in volcanology and related fields. The Institute of Earth Sciences is leading within the Nordic countries in disciplines such as volcanology and plate tectonics, and furthermore holds special expertise in climatology, glaciology, sustainable environments and geothermal processes.

• ZERO - Zackenberg Ecological Research Operations (Danmark og Grønland)
  Zackenberg Research Station (74º28’ N, 20º34’ W) is a Greenlandic research infrastructure in high arctic Northeast Greenland, 25 km northwest of the settlement Daneborg, a military outpost with twelve inhabitants. Zackenberg Research Station is operated by the Zackenberg Secretariat at the Department of Bioscience, Aarhus University.

• NERO - Nuuk Ecological Research Operations (Danmark og Grønland)
  Nuuk Basic is an extensive cross-disciplinary ecological monitoring program in low Arctic West Greenland. Nuuk Basic studies the effect of climate change and variability on terrestrial and marine ecosystems. The study area is situated in Kobbefjord (64°07’N / 51°21'W), approximately 20 km from Nuuk, the Capital of Greenland.

• ARC - Arctic Research Centre (Danmark og Grønland)
  Center under Aarhus University.

• DCE - Nationalt Center for Miljø og Energi (Danmark og Grønland)
  Center Under Aarhus University.

• Isaaffik Arctic Gateway (Danmark og Grønland)
  Connecting Arctic Research, Education, Consultancy and Logistics within the Kingdom of Denmark.

• Klimadebat (Danmark og Grønland)
  (In Danish) Online Danish debate forum about climate and energy.

• Polar Portal (Danmark og Grønland)
  On this website, Danish research institutions display the results of their monitoring of the Greenland Ice Sheet and the sea ice in the Arctic. The main purpose of the site is to make updated information from this monitoring available to the general public, both nationally and internationally.

• Carleton College – Thermodynamics
  Short introduction to thermodynamics on the college of Carleton.

• Nagra/PSI Chemical Thermodynamic Database
  The PSI/Nagra Chemical Thermodynamic Database 12/07 is the default database for GEMS-PSI.

• Geofysiksamarbejdet
  (In Danish) The GeoPhysicsCollaboration does research and development of geophysical methods to support groundwater mapping in Denmark.
• SkyTEM Geophysical Surveys
  SkyTEM is a leading airborne geophysical survey company offering the acquisition and advanced processing of transient electromagnetic (TEM), magnetic and radiometric data.
• EARTHDATA 
  The Earth Science Data Systems (ESDS) Program provides full and open access to NASA’s collection of Earth science data.
• DJF geodata (Det Jordbrugsvidenskabelige Fakultet)
  (In Danish) Data from registrations of the soil in Denmark (from 1975 and forward)
• GEUS: GERDA - GEofysisk Relationel DAtabase
  (In Danish) Project: GERDA – GEophysical Relational DAtabase. Country wide database for geophysical data within the raw material and environmental areas.
• GEUS: MARTA - metadata base of shallow geophysical data
  The MARTA meta-database holds information on shallow seismic geophysical data stored in the GEUS archives. Besides information collected by GEUS and cooperating partners, MARTA is the official offshore raw material database for company geophysical data reported according to Danish Law.
• Seg Ebooks: Society of Exploration Geophysicists
  Collection of books and congress proceedings by the SEG.

• ATV Jord og Grundvand
  (In Danish) The foundation works actively to promote communication and exchange of knowledge about the areas of soil and groundwater pollution.      

• GEUS: JUPITER - Danmarks geologiske & hydrologiske database
  (In Danish, option to switch to English via. Google translate) Jupiter is GEUS 'nationwide database of groundwater, drinking water, raw materials, environmental and geotechnical data. Databasen er den fællesoffentlige database på området og indgår i Danmarks Miljøportal. The database is the common public database of the area and is part of Denmark's Environment Portal. Databasen er offentligt tilgængelig The database is publicly available. 

• GEUS: Well Data (DEEP WELLS) (Danmark)

• GEUS: Well Data (DEEP WELLS) (Grønland)

• USGC - Mineral Resources Program
  The USGS Mineral Resources Program delivers unbiased science and information to understand mineral resource potential, production, consumption, and how minerals interact with the environment.

• Mineralogy Database
  Contains 4,714 individual mineral species descriptions with links and a comprehensive image library. Each mineral has a page linked to tables devoted to crystallography, crystal structures, X-Ray powder diffraction, chemical composition, physical and optical properties, Dana's New classification, Strunz classification, mineral specimen images, and alphabetical listings of mineral species. 

• COD - Crystallography Open Database
  Collection of crystal structures of organic, inorganic, metal-organic compounds and minerals, excluding biopolymers. (Open Access)

• American Mineralogist Crystal Structure Database
  Crystal structure database that includes every structure published in the American Mineralogist, The Canadian Mineralogist, European Journal of Mineralogy and Physics and Chemistry of Minerals, as well as selected datasets from other journals.

• IUCr - International Union of Crystallography
  The IUCr aims to promote international cooperation in crystallography and to contribute to all aspects of crystallography, to promote international publication of crystallographic research, to facilitate standardization of methods, units, nomenclatures and symbols, and to form a focus for the relations of crystallography to other sciences.

• Marslab - Mars Simuleringslaboratoriet
  The Mars Simulation Laboratory is an interdisciplinary research collaboration of biologists, chemists, geologists and physicists who work together on joint research related to the planet Mars.

• ESA - European Space Agency
  The European Space Agency (ESA) is Europe's gateway to space. Its mission is to shape the development of Europe's space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world.

• LPI - Lunar and Planetary Institute Abstract Collection
  The Lunar and Planetary Institute is a research institute that provides support services to NASA and the planetary science community, and conducts planetary science research under the leadership of staff scientists, visiting researchers, and postdoctoral fellows.

• Lunar Chart (LAC) Series
  Lunar Charts from the LPI (Lunar and Planetary Institute)

• NASA
  National Aeronautics and Space Administration of the United States of America.

• NASA: Ames Research Center
  NASA Ames Research Center, one of ten NASA field centers, is located in the heart of California's Silicon Valley.

• NASA: Goddard Space Flight Center
  Goddard is the operational home of the venerable Hubble Space Telescope.

• NASA: Visible Earth
  A catalog of NASA images and animations of Earth.

• NASA: Earth Observatory
  The Earth Observatory’s mission is to share with the public the images, stories, and discoveries about the environment, Earth systems, and climate that emerge from NASA research, including its satellite missions, in-the-field research, and models.

• HiRISE - High Resolution Imaging Science Experiment

• Google Moon

• ICS - International Commission on Stratigraphy 
  The ICS's primary objective is to precisely define global units (systems, series, and stages) of the International Chronostratigraphic Chart that, in turn, are the basis for the units (periods, epochs, and age) of the International Geologic Time Scale; thus setting global standards for the fundamental scale for expressing the history of the Earth.

Denmark

• Geocenter Danmark
  The Geocenter is a national center of geoscientific research, education, consulting, innovation and publishing at a high international level.

• DGF - Dansk Geologisk Forening
  The Geological Society of Denmark was founded in 1893 to promote interest in geology and to establish a forum for geologists and others with interest for geology.

• GEUS - Geologiske Undersøgelser for Danmark og Grønland
  Geoscientific studies, research, consultancy and geological mapping

• Det Kongelige Danske Geografiske Selskab
  (In Danish) The goal of The Royal Danish Geographical Society is to promote the knowledge of the earth, its inhabitants and to expand interest in geographical science. 

Europe

• BGS - British Geological Survey
  Geoscientific data, information and knowledge.

• EAGE - European Association of Geoscientists & Engineers
  EAGE is a not-for-profit association for geoscientists and engineers with almost 19,000 members worldwide. All members of EAGE are professionally involved in (or studying) geophysics, petroleum exploration, geology, reservoir engineering, mining and mineral exploration, civil engineering, tunneling and environmental matters.

• EGU - European Geosciences Union
  Is a non-profit international union of scientists with over 12,500 members from all over the world. Membership is open to individuals who are professionally engaged in or associated with geosciences and planetary and space sciences and related studies, including students and retired seniors.

• GA - Geologists´ Association, London
  Since its formation in 1858, the GA has actively promoted the study of geology to all who are interested in the past, present and future of the natural world.

• GS - The Geological Society, London
  Aims are to improve knowledge and understanding of the Earth, to promote Earth science education and awareness, and to promote professional excellence and ethical standards in the work of Earth scientists, for the public good.

• The Royal Society (UK and the Commonwealth)

• DGGV - Deutsche Geologische Gesellschaft - Geologische Vereinigung

• Geozentrum Hannover

• GTK - The Geological Survey of Finland

• NGF - Norsk Geologisk Forening

• NGU - Norges Geologiske Undersøkelse

• NPF - Norsk Petroleumsforening

• SGU - Sveriges Geologiska Undersökning

USA, Canada & Australia

• AGS - American Geographical Society
• AGU - American Geophysical Union
• GSA - The Geological Society of America
• MSA - Mineralogical Society of America
• SSA - Seismological Society of America
• USGS - U.S. Geological Survey
• CSPG - Canadian Society of Petroleum Geologists
• Geoscience Australia
• Geochemical Society
• PALASS - The Palaeontological Association
• SEG - Society of Exploration Geophysicists
• SEPM - Society for Sedimentary Geology

International

• Geology.com
• IUGS - International Union of Geological Sciences
• Unesco - Natural Sciences