EVENTO DE EXTENSÃO 2017

O Grupo de pesquisa do Centro de Estudos do Mar - Fenômenos das Descargas Atmosféricas, da UFPR irá promover no dia 14 de Janeiro de 2017, na praia de Matinhos, o II evento de extensão - Litoral em Alerta.

Este evento possui o objetivo de esclarecer dúvidas quanto aos perigos dos raios, principalmente durante o verão, e em particular na região litorânea do estado do Paraná. Também pretende apresentar a comunidade em geral um estudo realizado sobre a densidade de raios no litoral do Paraná, através de uma pesquisa feita por alunos e professores do CEM-UFPR.
Alunos e professores do CEM-UFPR estarão presentes no local, com folders, poster e alguns equipamentos usados no monitoramento deste fenômeno atmosférico. Haverá a participação de estudantes de outras instituições colaboradoras e do incentivo do SIMEPAR.

Prestigie, participe!

Antenas de celular medem chuva com precisão

Sensor de chuva

Uma das maiores dificuldades que os meteorologistas encontram para fazer melhores previsões é a falta de sensores que lhes deem dados estatísticos suficientes para uma amostragem significativa e com alta resolução espacial.
Hoje, eles dependem de pluviômetros, geralmente instalados em estações muito espaçadas, ou de radares, muito caros e dificilmente disponíveis para todas as áreas.
A boa notícia é que a rede de telefonia celular - mais especificamente, as ondas que trafegam entre as antenas e entre as antenas e os celulares - pode se transformar em um gigantesco sensor capaz de monitorar a chuva em grandes áreas e com alta resolução.

 A qualidade dos dados de precipitação obtidos pelo programa é a mesma dos pluviômetros, mas com a grande vantagem da maior resolução espacial e da disponibilização dos dados em tempo real. [Imagem: Christian Chwala]


A descoberta de que as gotas de chuva atenuam a propagação das ondas eletromagnéticas de uma forma mensurável foi feita por Christian Chwala e seus colegas do Instituto de Tecnologia Karlsruhe, na Alemanha.
Chwal desenvolveu um programa de computador que consegue derivar a informação sobre as precipitações atmosféricas a partir de flutuações nos sinais recebidos pelas antenas das estações de telefonia celular. Segundo ele, a técnica poderá ser a solução para áreas com pequena cobertura de sensores, como os países mais pobres.

Pluviômetro eletromagnético

"Os pingos de chuva são quase tão grandes quanto o comprimento de onda da radiação de micro-ondas dos links de rádio operando em frequências de 15 a 40 gigahertz. Por esta razão, eles atenuam fortemente a radiação nesta faixa de frequência," explica o professor Harald Kunstmann, coordenador do trabalho.
Quanto mais forte for a chuva, maior é a diminuição da potência do sinal entre duas antenas. Os usuários de celulares dificilmente notam o efeito, a não ser em casos de tempestades, quando então o sinal é interrompido e a ligação cai.
A qualidade dos dados de precipitação obtidos pelo programa é a mesma dos pluviômetros, mas com a grande vantagem da maior resolução espacial e da disponibilização dos dados em tempo real. "O limite de detecção é uma chuva de um milímetro por hora, e os dados ficam disponíveis com um retardo de apenas um minuto," disse Chwala.

Bibliografia:

Real-time data acquisition of commercial microwave link networks for hydrometeorological applications
Christian Chwala, Felix Keis, Harald Kunstmann
Atmospheric Measurement Techniques
Vol.: 9, Issue 3, 991-999
DOI: 10.5194/amt-9-991-2016

Onde caem mais raios na Terra?

Censo de raios
Embora seja um questionamento comum aos estatísticos, as probabilidades de uma pessoa ser atingida por um raio são quase sempre retratadas como muito remotas. No entanto, no mês de maio, incidentes envolvendo raios bateram recordes ao atingirem dezenas de pessoas ao redor do mundo.
Em Bangladesh, durante violentas tempestades tropicais, foram 65 vítimas fatais em apenas quatro dias. Na França e na Alemanha, dezenas de pessoas ficaram feridas durante fortes chuvas, incluindo um grupo de crianças de 9 a 11 anos, atingidas por um raio durante uma partida de futebol. No Brasil houve ao menos uma vítima fatal no período.
Mas onde caem mais raios no planeta Terra? E por que caem tantos em alguns lugares?

Sensor de raios

Liderados pela professora Rachel Albrecht, do Instituto de Astronomia, Geofísica e Ciências Atmosféricas da USP, pesquisadores da NASA e de diversas universidades se reuniram para tentar responder a essas perguntas.
Usando um sensor de raios chamado LIS (Lightning Imaging Sensor), a bordo do satélite de observações TRMM (Tropical Rainfall Measuring Mission) da Nasa, a equipe compôs um mapa que mostra as principais zonas de incidência de raios ao redor do planeta.
"O sensor foi lançado no final de 1997 e descomissionado em 2015," conta Rachel. "Desde 2009, monitoramos os máximos de raios, fazendo a climatologia, e agora, como o satélite não está mais operando, encerramos com 16 anos de dados, incluindo de 1998 até 2013."

Video Raios Maracibo

Raios na região do Lago Maracaibo, na Venezuela, o local onde caem mais raios no mundo.

Onde caem mais raios na Terra?

Os dados permitiram compor um ranking que lista os 500 locais com maior incidência de raios no mundo.
Individualmente, o Lago Maracaibo, na Venezuela, é a capital mundial dos raios. Até então, a maior densidade de raios tinha sido encontrada no Congo, na África.
De fato, 283 locais apontados no mapa estão na África, uma região que, de acordo com Rachel, tem desenvolvimento de sistemas convectivos de mesoescala durante o ano inteiro e numa área grande.
O Brasil começa a aparecer na posição 191, e o local com mais raios fica localizado ao noroeste de Manaus, próximo do Rio Negro. Contudo, quando se somam todos os raios sobre o território nacional, o Brasil é o país com mais raios no mundo, devido a sua dimensão continental e por estar nos trópicos. "Só no Brasil temos, em média, aproximadamente 110 milhões de raios totais por ano", disse Rachel.

[..."Hoje temos cerca de 120 mortes por ano e 500 pessoas feridas, ou seja, 620 pessoas são atingidas por ano no Brasil. 
O Brasil é o país com maior incidência de raios no mundo.
"São entre 50 e 60 milhões de descargas por ano, com maior volume no verão", todas as regiões do país têm áreas com alta incidência de raios, como a parte oeste dos estados da Região Sul e a área da Grande São Paulo, no Sudeste, e o estado do Piauí, no Nordeste....]


Indicativos de mudanças climáticas

Uma das principais conclusões do estudo é que a incidência de raios está relacionada com as características dos respectivos locais, como a topografia ou vegetação.
Para o futuro, os pesquisadores pretendem analisar se, nesses 16 anos, houve um aumento ou uma diminuição na intensidade das tempestades, não apenas no número de raios, mas se estão mais intensas ou não. A ideia é "ter um indício do que está ocorrendo em termos de mudanças climáticas nessa última década e meia", finaliza Rachel.


Referência:

Where are the lightning hotspots on Earth?
Rachel I. Albrecht, Steven J. Goodman, Dennis E. Buechler, Richard J. Blakeslee, Hugh J. Christian
Bulletin of the American Meteorological Society
DOI: 10.1175/BAMS-D-14-00193.1

Sons da Aurora Boreal

Em 2012, um grupo liderado pelo professor Unto Laine, da Universidade Aalto, na Finlândia, demonstrou que um daqueles "mitos históricos" - os relatos de que a aurora boreal emitia sons - era um fato.
E, mais do que isso, a equipe demonstrou que, embora as Luzes do Norte ocorram a altitudes entre 80 e 150 km, a fonte dos sons associados a elas parecia estar localizada bem perto do chão, a uma altitude de aproximadamente 70 metros.
Agora a equipe encontrou uma explicação para o mecanismo que cria o som e confirmou sua origem de baixa altitude. Para isso, eles combinaram medições acústicas locais com os perfis de temperatura atmosférica medidos pelo Instituto Meteorológico da Finlândia.

Camada de inversão

Em um fenômeno que a equipe chamou de "hipótese da camada de inversão", os estalidos e crepitares associados com a Aurora Boreal surgem quando a tempestade geomagnética que produz as luzes na alta atmosfera ativa as cargas elétricas que se acumularam na camada de inversão da atmosfera, fazendo-as descarregar como se fossem minúsculos raios.
"As temperaturas geralmente caem quanto maior a altitude. No entanto, quando as temperaturas estão bem abaixo de zero e, em geral em condições climáticas claras e calmas durante a tarde e a noite, o frio fica perto da superfície e o ar mais quente fica em cima.
"Esse ar quente não se mistura, ele sobe em direção a uma camada mais fria levando cargas negativas do solo. A camada de inversão forma uma espécie de tampa, dificultando os movimentos verticais das cargas. O ar mais frio acima dela é positivamente carregado.
"Finalmente, uma tempestade geomagnética faz com que as cargas acumuladas descarreguem na forma de faíscas que criam pulsos magnéticos e sonoros mensuráveis," explica o professor Laine.

Mistérios das auroras boreais

De acordo com o pesquisador, a hipótese da camada de inversão também dá uma explicação crível de por quê os sons das auroras boreais só são ouvidos em condições meteorológicas calmas.
Ele enfatiza que a hipótese não exclui outros mecanismos, mas esta é a primeira explicação para todos os três mistérios relacionados aos sons das auroras polares.
"Além do mecanismo que gera o som, isso nos ajuda a entender como podemos ouvir o som quando a fonte de luz da aurora está a uma distância de 80 a 100 km. A hipótese da camada de inversão também oferece respostas para como é possível que os eventos sonoros ocorram quase simultaneamente com as observações visuais: partindo de uma altitude de 75 metros, o som atinge o ouvido humano em apenas 0,2 segundo," conclui ele.

Bibliografia:

Auroral Acoustics project - a progress report with a new hypothesis
Unto Kalervo Laine
Vol.: To be published

 

Fonte: http://www.inovacaotecnologica.com.br/noticias/noticia.php?artigo=sons-da-aurora-boreal&id=010125160627

Blitzdienst: Die Zähler des Zeus

Wo immer Zeus in Europa seinen Blitz schleudert, Stephan Thern registriert es. Sein Blitzdienst meldet nur Sekunden später, wo es eingeschlagen hat. 

 

Stephan Thern vom Siemens Blitz-Informationsdienst (BLIDS) in Karlsruhe (Baden-Württemberg) stehtvor einer Bildmontage des Karlsruher Schlosses. Foto: dpa

Karlsruhe.Wenn sich am Himmel Gewitterwolken zusammenballen, kann Stephan Thern gar nicht anders, als seinen Computer anzuwerfen. „Ich will dann natürlich wissen, ob wir das Unwetter auf dem Schirm haben“, erzählt der Elektrotechniker und ein kleines Lächeln umspielt seinen Mund. Bislang hat ihn die Technik nie enttäuscht.

150 Stationen in Europa

Der von Thern geführte Blitzdienst von Siemens in Karlsruhe registriert im Schnitt rund eine Million Entladungen im Jahr über Deutschland. Für die Aufzeichnung reichen 16 Messpunkte in Deutschland aus sowie weitere rund 150 Stationen, die Siemens gemeinsam mit Partnern in Europa betreibt. Für die Informationen interessieren sich vor allem Energieversorger und Flughäfen, Versicherungen und Organisatoren von Großveranstaltungen.

Die Blitze lassen sich leicht messen. Bei ihrer Entladung setzen sie eine elektromagnetische Welle frei, die sich mit hoher Geschwindigkeit in alle Richtungen ausbreitet. Die Messstationen in einer Entfernung von bis zu 600 Kilometern können dieses Feld garantiert aufzeichnen. „Die Reichweite ist aber weit größer“, erklärt Thern. „Wir haben mit unserer Karlsruher Station schon Blitze über Portugal gemessen.“

Wird ein Blitz von mindestens zwei Stationen aufgezeichnet, kann anhand des Abgleichs von Zeit und Entfernung der Punkt der Entladung errechnet werden. Je mehr Stationen Daten liefern, desto exakter kann der Blitzdienst den Ort eingrenzen. „Im Moment liegen wir bei einer Genauigkeit von 200 bis 700 Metern.“

Wo Blitze eingeschlagen haben, interessiert in erster Linie die Betreiber von Freileitungen. „Wenn bei ihnen eine Leitung ausfällt, wollen sie wissen, ob ein Blitz dafür verantwortlich ist oder doch ein umgefallener Baum“, erklärt Thern. „Falls wir den Blitz bestätigen, kann die Leitung schnell wieder ans Netz genommen werden, bei einem Baum dauern die Aufräumarbeiten etwas länger.“

Versicherungen greifen auf Daten zurück

Versicherungen benötigen die Daten, um zu prüfen, ob sie Schadenersatz leisten müssen. „Die meisten Schäden entstehen ja nicht durch den Blitzschlag selbst, sondern durch die Überspannung. Das kann zu Kurzschlüssen in Geräten führen, die in einem Radius von 2,5 Kilometern vom Blitzschlag entfernt stehen“, erläutert Thern.

Nach Angaben des Gesamtverbandes der Deutschen Versicherungswirtschaft werden pro Jahr zwischen 300 000 und 550 000 durch Blitz verursachte Schadensfälle gemeldet. Die Gesamtschadenssumme liegt bei rund 300 Millionen Euro. Mit Hilfe des Blitzdienstes können die Versicherungen schnell sehen, ob die Angaben ihrer Kunden stimmig sind oder nicht.

Doch das Blitz-Team belässt es nicht bei der bloßen Zählung. Seine Daten dienen auch der Warnung. „Wir haben sogar einige Kunden, für die wir sensible Anlagen abschalten können, wenn sich ein Gewitter nähert.“ Darunter fallen Rechenzentren und Windräder älterer Bauart, deren Rotorblätter sich bei Blitzeinschlägen lösen können.

Seit einigen Jahren arbeitet der Dienst auch an einer Kombination der Blitzeinschläge mit anderen Wetterdaten, um Gewitterverläufe besser vorhersagen zu können. „Das ist dann vor allem für Großveranstaltungen interessant, die wissen wollen, was da auf sie zukommt – ob sie evakuieren müssen oder nicht.“ Erste Interessenten gebe es bereits.

Hinweise auf den Klimawandel, bei dem heftigere Stürme vorausgesagt werden, kann Thern in seinen Daten nicht finden. „Dafür sind die Schwankungen zwischen den einzelnen Jahren zu hoch.“ Im Schnitt wird eine deutsche Region an 16 bis 36 Tagen im Jahr von Gewittern heimgesucht, 95 Prozent aller Blitze schlagen zwischen Mai und September zu.

Die Höhenlagen im Süden sind dabei stärker betroffen als die flachen Lagen im Norden. Dort ziehen allerdings Windräder Blitze magisch an. „Das sind die reinsten Blitzfänger“, sagt Thern und zeigt auf die Auswertung von 30 Einschlägen in Norddeutschland an einem Tag im Mai. In fast allen Fällen stand eine Windkraftanlage im Mittelpunkt.

In den vergangenen Wochen wurde Thern nur selten von Gewitterwolken an seinen Computer gelockt. „Bislang hatten wir ein sehr ruhiges Jahr“, sagt er, obwohl es in einigen Regionen heftige Pfingstunwetter gab. Aber der richtige Sommer kommt ja vielleicht noch, und dann gibt es wieder Feuerwerk auf den Rechnern: wenn mit einer Gewitterfront bis zu 200 000 Blitze über Deutschland niedergehen. (dpa)

Font: http://www.mittelbayerische.de/panorama-nachrichten/blitzdienst-die-zaehler-des-zeus-21934-art1088623.html

Laser é capaz de guiar os Raios

O laser faz com que a descarga elétrica execute caminhos complexos e desvie de obstáculos. [Imagem: Matteo Clerici - 10.1126/sciadv.1400111]


Raios guiados por laser

Pára-raios são bons, mas muito longe do ideal, sobretudo porque eles não estabelecem o caminho do raio, que geralmente espalha-se pelas cercanias.
A ideia de Matteo Clerici, do Instituto Nacional de Pesquisas Científicas do Canadá, é usar raios laser para guiar cuidadosamente o raio, até o seu destino final no solo.
O conceito funcionou bem, ao menos em pequena escala, em raios criados em laboratório, simulados por descargas elétricas entre dois eletrodos.
Clerici conseguiu dirigir com precisão os raios simulados, fazendo-os não apenas cair no lugar certo, mas até mesmo desviar-se de obstáculos no meio do caminho.
As descargas elétricas também foram dirigidas para seguir linhas retas ou trajetórias parabólicas entre a origem e o destino.

Raio desvia de obstáculo

Os experimentos mostraram que o trajeto do raio pode ser controlado ajustando o "formato" dos feixes de laser. Combinando diversos feixes, foi possível até mesmo fazer o raio atingir o receptor seguindo uma trajetória em "S".
Quando controlada para desviar de obstáculos, a descarga mudou o trajeto com precisão, passando sem danificar o objeto que servia de obstáculo.


É o formato do feixe de laser que estabelece a trajetória do raio. [Imagem: Matteo Clerici - 10.1126/sciadv.1400111]


O experimento é mais simples e possibilita um controle muito maior do que experimento similar realizado em 2012 por pesquisadores franceses, que fizeram os raios seguirem a trajetória retilínea de um laser pulsado.
As aplicações práticas, porém, ao menos em raios de verdade, deverão demorar, uma vez que também estes novos experimentos exigiram lasers de alta potência e manipularam descargas de poucos centímetros.
Mas descargas elétricas não acontecem apenas durante tempestades, sendo usadas diariamente em todos os motores a combustão e em equipamentos de solda, por exemplo, o que pode indicar aplicações promissoras em outras áreas.

Bibliografia:

Laser-assisted guiding of electric discharges around objects
Matteo Clerici, Yi Hu, Philippe Lassonde, Carles Milián, Arnaud Couairon, Demetrios N. Chrisodoulides, Zhigang Chen, Luca Razzari, François Vidal, François Légaré, Daniele Faccio, Roberto Morandotti
Science Advances
Vol.: 1, No. 5
DOI: 10.1126/sciadv.1400111
 

O mapa de um trovão

Pela primeira vez os cientistas conseguiram capturar um mapa da explosão de radiação a partir de um relâmpago. O Héliofísico Maher Dayeh conseguiu registrar um mapa sonoro do trovão.
 

Uma corrente elétrica rapidamente flui do centro de cargas negativo da nuvem e segue para o solo, o relâmpago rapidamente aquece e expande o ar a sua volta, gerando ondas de choque.
Fonte: https://www.sciencenews.org/article/scientists-take-first-picture-thunder

Qual área de pesquisa seguir?

Esta é uma lista de algumas áreas de pesquisa. Foi retirada das opções de área do Journal of Geophysical Research Atmospheres, a serem escolhidas no momento de submissão de "qualquer" artigo, para aquele Journal.

ATMOSPHERIC COMPOSITION AND STRUCTURE

Aerosols and particles (0345, 4801, 4906)

Airglow and aurora

Air/sea constituent fluxes (3339, 4504)

Biosphere/atmosphere interactions (0426, 1610)

Chemical kinetic and photochemical properties

Cloud optics

Cloud physics and chemistry

Cloud/radiation interaction

Constituent sources and sinks

Evolution of the atmosphere (1610, 8125)

Exosphere

Geochemical cycles (1030)

Ion chemistry of the atmosphere (2419, 2427)

Middle atmosphere: composition and chemistry

Middle atmosphere: constituent transport and chemistry (3334)

Middle atmosphere: energy deposition (3334)

Planetary atmospheres (5210, 5405, 5704)

Pollution: urban and regional (0305, 0478, 4251, 4325)

Pressure, density, and temperature

Thermosphere: composition and chemistry

Thermosphere: energy deposition (3369)

Radiation: transmission and scattering

Troposphere: composition and chemistry

Troposphere: constituent transport and chemistry

Volcanic effects (4301, 8409)

Instruments and techniques

General or miscellaneous

BIOGEOSCIENCES

Agricultural systems

Anoxic and hypoxic environments (4802, 4834)

Astrobiology and extraterrestrial materials

Benthic processes (4804)

Bioavailability: chemical speciation and complexation

Biodiversity

Biogeochemical kinetics and reaction modeling (0414, 0793, 1615, 4805, 4912)

Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)

Biogeophysics

Bioremediation

Biomineralization

Biomolecular and chemical tracers

Bio-optics

Biosignatures and proxies

Biosphere/atmosphere interactions (0315)

Carbon cycling (4806)

Climate dynamics (1620)

Computational methods and data processing

Contaminant and organic biogeochemistry (0792)

Data sets

Diel, seasonal, and annual cycles (4227)

Ecosystems, structure and dynamics (4815)

Estuarine and nearshore processes (4235)

Evolutionary geobiology

Geomicrobiology

Hydrothermal systems (1034, 3017, 3616, 4832, 8135, 8424)

Instruments and techniques

Isotopic composition and chemistry (1041, 4870)

Life in extreme environments

Limnology (1845, 4239, 4942)

Macro- and micropaleontology (3030, 4944)

Marine systems (4800)

Metals

Microbe/mineral interactions

Microbiology: ecology, physiology and genomics (4840)

Modeling (1952, 4316)

Natural hazards (4308)

Nitrogen cycling

Nutrients and nutrient cycling (4845, 4850)

Oxidation/reduction reactions (4851)

Paleoclimatology and paleoceanography (3344, 4900)

Permafrost, cryosphere, and high-latitude processes (0702, 0716)

Plant ecology (1851)

Pollution: urban, regional and global (0345, 4251, 4325)

Remote sensing

Restoration

Riparian systems (0744, 1856)

Science policy (6620)

Soils/pedology (1865)

Sulfur cycling

Trace element cycling (4875)

Trace gases

Food webs and trophodynamics (4817)

Urban systems (4325)

Water/energy interactions (1878)

Water quality

Wetlands (1890)

General or miscellaneous

New fields (not classifiable under other headings)

COMPUTATIONAL GEOPHYSICS (1980, 3200, 3252, 4307, 4314, 7833)

Agent-based models

Cellular automata

Data analysis: algorithms and implementation

Data management

Data presentation and visualization (1994)

Hardware solutions

Image processing

Modeling (1952, 4255, 4316)

Model verification and validation

Neural networks, fuzzy logic, machine learning (1942)

Numerical solutions (4255)

Instruments and techniques

General or miscellaneous

CRYOSPHERE (4540)

Permafrost (0475, 4308)

Seasonally frozen ground

Active layer

Thermokarst

Periglacial processes

Cryosol

Clathrate

Cryobiology (0475)

Tundra (9315)

Glaciers

Rock glaciers

Ice cores (4932)

Ice sheets

Ice shelves

Ice streams

Icebergs

Icing (aufeis, naled)

Snow (1827, 1863)

Ice (1863)

Snowmelt

Avalanches (4302)

Rivers (0483, 1856)

Lakes (9345)

Ponds

Sea ice (4540)

Polynas (4540)

Leads (4540)

Remote sensing

Engineering

Mass balance (1218, 1223)

Energy balance

Thermodynamics (1011, 3611, 8411)

Thermal regime

Properties

Distribution

Dynamics

Glaciology (1621, 1827, 1863)

Weathering (1625, 1886)

Contaminants (0432)

Biogeochemistry (0412, 0414, 1615, 4805, 4912)

Instruments and techniques

Modeling (1952, 4316)

General or miscellaneous

EDUCATION

Elementary and secondary education

Post-secondary education

Informal education

Curriculum and laboratory design

Teaching methods

Teacher training

Evaluation and assessment

Instructional tools

Geoscience education research

Diversity

ELECTROMAGNETICS

Antenna arrays

Antennas

Biological effects

Electromagnetic theory

Guided waves

Inverse scattering

Measurement and standards

Nonlinear electromagnetics

Numerical methods

Optics (4264)

Plasmas

Random media and rough surfaces

Reflectors and feeds

Scattering and diffraction

Signal processing and adaptive antennas (6974)

Singularity expansion method

Transient and time domain

Wave propagation (2487, 3285, 4275, 4455, 6934)

Instruments and techniques

General or miscellaneous

EXPLORATION GEOPHYSICS

Computational methods: seismic

Computational methods: potential fields (1214)

Continental structures (8109, 8110)

Data processing

Downhole methods

Gravity methods (1219)

Magnetic and electrical methods (5109)

Oceanic structures

Radioactivity methods

Remote sensing

Seismic methods (3025, 7294)

Instruments and techniques

General or miscellaneous

GEOCHEMISTRY

Geochemical modeling (3610, 8410)

Thermodynamics (0766, 3611, 8411)

Reactions and phase equilibria (3612, 8412)

Subduction zone processes (3060, 3613, 8170, 8413)

Mid-oceanic ridge processes (3614, 8416)

Intra-plate processes (3615, 8415)

Hydrothermal systems (0450, 3017, 3616, 4832, 8135, 8424)

Alteration and weathering processes (3617)

Magma chamber processes (3618)

Magma genesis and partial melting (3619)

Mantle processes (3621)

Composition of the core

Composition of the continental crust

Composition of the oceanic crust

Composition of the hydrosphere

Composition of the biosphere

Composition of the mantle

Composition of the moon

Composition of the planets

Composition of meteorites (3662, 6240)

Composition of aerosols and dust particles

Geochemical cycles (0330)

Major and trace element geochemistry

Radiogenic isotope geochemistry

Stable isotope geochemistry (0454, 4870)

Mineral and crystal chemistry (3620)

Fluid and melt inclusion geochemistry

Marine geochemistry (4835, 4845, 4850)

Sedimentary geochemistry

Organic and biogenic geochemistry

Planetary geochemistry (5405, 5410, 5704, 5709, 6005, 6008)

Field relationships (3690, 8486)

Instruments and techniques

General or miscellaneous

GEOCHRONOLOGY

Quaternary geochronology

Sidereal geochronology

Radioisotope geochronology

Isotopic disequilibrium dating

Chemical and biological geochronology

Geomorphological geochronology

Correlative geochronology

Thermochronology

Tephrochronology (8455)

Cosmogenic-nuclide exposure dating (4918)

Extinct radionuclide geochronology

Planetary and lunar geochronology

Sedimentary geochronology

Instruments and techniques

General or miscellaneous

GEODESY AND GRAVITY

Standards and absolute measurements

Instruments and techniques

Integrations of techniques

Satellite geodesy: results (6929, 7215, 7230, 7240)

Satellite geodesy: technical issues (6994, 7969)

Space geodetic surveys(4337)

Control surveys

Seismic cycle related deformations (6924, 7209, 7223, 7230)

Transient deformation (6924, 7230, 7240)

Tectonic deformation (6924)

Non-tectonic deformation

Earth's interior: composition and state (7207, 7208, 8105, 8124)

Earth's interior: dynamics (1507, 7207, 7208, 8115, 8120)

Rheology of the lithosphere and mantle (7218, 8160)

Gravity anomalies and Earth structure (0920, 7205, 7240)

Geopotential theory and determination (0903)

Time variable gravity (7223, 7230)

Reference systems

Earth rotation variations

Ocean/Earth/atmosphere/hydrosphere/cryosphere interactions (0762, 1218, 3319, 4550)

Mass balance (0762, 1223, 1631, 1836, 1843, 3010, 3322, 4532)

Atmosphere monitoring with geodetic techniques (6952)

Ocean monitoring with geodetic techniques (1225, 1641, 3010, 4532, 4556, 4560, 6959)

Global change from geodesy (1222, 1622, 1630, 1641, 1645, 4556)

Lunar and planetary geodesy and gravity (5417, 5450, 5714, 5744, 6019, 6250)

General or miscellaneous (1709)

GEOMAGNETISM AND PALEOMAGNETISM

Archeomagnetism

Biogenic magnetic minerals

Core processes (1213, 8115)

Dynamo: theories and simulations

Environmental magnetism

Geomagnetic excursions

Geomagnetic induction

Magnetic anomalies: modeling and interpretation

Magnetic fabrics and anisotropy

Magnetic mineralogy and petrology

Magnetostratigraphy

Paleointensity

Paleomagnetic secular variation

Paleomagnetism applied to tectonics: regional, global

Paleomagnetism applied to geologic processes

Rapid time variations

Reference fields: regional, global

Remagnetization

Reversals: process, timescale, magnetostratigraphy

Rock and mineral magnetism

Satellite magnetics: main field, crustal field, external field

Spatial variations: all harmonics and anomalies

Spatial variations attributed to seafloor spreading (3005)

Time variations: diurnal to decadal

Time variations: secular and longer

Instruments and techniques

Planetary magnetism: all frequencies and wavelengths

General or miscellaneous

GLOBAL CHANGE

Abrupt/rapid climate change (4901, 8408)

Atmosphere (0315, 0325)

Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 4805, 4912)

Climate variability (1635, 3305, 3309, 4215, 4513)

Climate dynamics (0429, 3309)

Cryospheric change (0776)

Earth system modeling (1225, 4316)

Geomorphology and weathering (0790, 1824, 1825, 1826, 1886)

Global climate models (3337, 4928)

Coupled models of the climate system

Impacts of global change (1225, 4321)

Land/atmosphere interactions (1218, 1843, 3322)

Land cover change

Oceans (1616, 3305, 4215, 4513)

Regional climate change (4321)

Remote sensing (1855, 4337)

Sea level change (1222, 1225, 4304, 4556)

Solid Earth (1225)

Solar variability (7537)

Water cycles (1836)

Instruments and techniques

General or miscellaneous

HISTORY OF GEOPHYSICS

Atmospheric sciences

Biogeosciences

Computational geophysics

Cryosphere

Geochronology

Geodesy (1299)

Geomagnetism and paleomagnetism

Hydrology

Nonlinear geophysics

Ocean sciences

Planetology

Seismology

Solar/planetary relationships

Tectonophysics

Volcanology, geochemistry, and petrology

Instruments and techniques

General or miscellaneous

HYDROLOGY

Anthropogenic effects (4802, 4902)

Catchment

Chemistry of fresh water

Climate impacts (4321)

Computational hydrology

Dams

Debris flow and landslides (4303)

Desertification

Drought (4303)

Eco-hydrology

Energy budgets

Erosion

Estimation and forecasting (4315)

Evapotranspiration

Extreme events (4313)

Floods (4303)

Floodplain dynamics

Frozen ground

Geographic Information Systems (GIS)

Geomechanics

Geomorphology: general (1625)

Geomorphology: fluvial (1625)

Geomorphology: hillslope (1625)

Glaciology (0736, 0776, 1863)

Groundwater hydraulics

Groundwater hydrology

Groundwater quality

Groundwater/surface water interaction

Groundwater transport

Human impacts (4323)

Hydroclimatology

Hydrogeophysics

Hydrological cycles and budgets (1218, 1655)

Hydrometeorology

Hydrologic scaling

Infiltration

Irrigation

Land/atmosphere interactions (1218, 1631, 3322)

Limnology (0458, 4239, 4942)

Model calibration (3333)

Modeling (1952, 4316)

Monitoring networks

Numerical approximations and analysis (3336)

Overland flow

Plant ecology (0476)

Plant uptake

Precipitation (3354)

Precipitation-radar

Remote sensing (1640, 4337)

Reservoirs (surface)

River channels (0483, 0744)

Rocks: chemical properties

Rocks: physical properties

Streamflow

Sedimentation (4863)

Sediment transport (4558)

Snow and ice (0736, 0738, 0776, 1827)

Soils (0486)

Soil moisture

Stochastic hydrology

Surface water quality

Time series analysis (1988, 3270, 4277, 4475)

Uncertainty assessment (1990, 3275)

Ungaged basins

Vadose zone

Water budgets

Water/energy interactions (0495)

Watershed

Water management (6334)

Water supply

Weathering (0790, 1625)

Wetlands (0497)

Instruments and techniques: modeling

Instruments and techniques: monitoring

General or miscellaneous

INFORMATICS

Community modeling frameworks

Community standards

Computational models, algorithms

Cyberinfrastructure

Data assimilation, integration and fusion

Data management, preservation, rescue

Data mining

Data and information discovery

Decision analysis (4324, 6309)

Emerging informatics technologies

Forecasting (2722, 4315, 7924)

Formal logics and grammars

Geospatial

GIS science

Data and information governance

High-performance computing

International collaboration

Interoperability

Knowledge representation and knowledge bases

Machine-to-machine communication

Machine learning (0555)

Markup languages

Metadata

Metadata: Provenance

Metadata: Quality

Modeling (0466, 0545, 0798, 1847, 4255, 4316)

Natural language processing

Numerical algorithms

Ontologies

Portals and user interfaces

Query languages for science, markup languages, ontologies

Real-time and responsive information delivery (4346)

Rules and logic

Scientific reasoning/inference

Semantic web and semantic integration

Sensor web

Social networks

Software tools and services

Software re-use

Spatial analysis and representation (0500, 3252)

Standards

Statistical methods: Descriptive (4318)

Statistical methods: Inferential (4318)

Temporal analysis and representation (1872, 3270, 4277, 4475)

Uncertainty (1873, 3275)

Virtual globes

Visualization and portrayal (0530)

Web Services

Workflow

General or miscellaneous

INTERPLANETARY PHYSICS

Coronal mass ejections (4305, 7513)

Corotating streams

Cosmic rays

Discontinuities (7811)

Ejecta, driver gases, and magnetic clouds

Energetic particles (7514)

Heliopause and solar wind termination

Heliosphere/interstellar medium interactions

Interplanetary dust

Interplanetary magnetic fields

Interplanetary shocks

Interstellar gas

MHD waves and turbulence (2752, 6050, 7836)

Neutral particles (7837)

Pickup ions

Planetary bow shocks

Plasma waves and turbulence

Solar cycle variations (7536)

Solar wind plasma

Solar wind sources

Instruments and techniques

General or miscellaneous

IONOSPHERE (6929)

Active experiments

Auroral ionosphere (2704)

Current systems (2721)

Electric fields (2712)

Equatorial ionosphere

Ion chemistry and composition (0335)

Ionization processes (7823)

Ionosphere/atmosphere interactions (0335)

Ionosphere/magnetosphere interactions (2736)

Ionospheric disturbances

Ionospheric dynamics

Ionospheric irregularities

Ionospheric storms (7949)

Meteor-trail physics

Midlatitude ionosphere

Modeling and forecasting

Particle acceleration

Particle precipitation

Planetary ionospheres (5435, 5729, 6026)

Plasma interactions with dust and aerosols (7849)

Plasma convection (2760)

Plasma temperature and density

Plasma waves and instabilities (2772)

Polar cap ionosphere

Solar radiation and cosmic ray effects

Topside ionosphere

Wave/particle interactions (7867)

Wave propagation (0689, 3285, 4275, 4455, 6934)

Instruments and techniques

General or miscellaneous

MAGNETOSPHERIC PHYSICS (6939)

Auroral phenomena (2407)

Cusp

Electric fields (2411)

Energetic particles: precipitating

Energetic particles: trapped

Field-aligned currents and current systems (2409)

Forecasting (1922, 4315, 7924, 7964)

Magnetic reconnection (7526, 7835)

Magnetopause and boundary layers

Magnetosheath

Magnetosphere: inner

Magnetosphere: outer

Magnetosphere interactions with satellites and rings

Magnetosphere/ionosphere interactions (2431)

Magnetospheric configuration and dynamics

Magnetotail

Magnetotail boundary layers

MHD waves and instabilities (2149, 6050, 7836)

Numerical modeling

Planetary magnetospheres (5443, 5737, 6033)

Plasma convection (2463)

Plasma sheet

Plasmasphere

Plasma waves and instabilities (2471)

Polar cap phenomena

Radiation belts

Ring current

Solar wind interactions with unmagnetized bodies

Solar wind/magnetosphere interactions

Magnetic storms and substorms (4305, 7954)

Substorms

Instruments and techniques

General or miscellaneous

MARINE GEOLOGY AND GEOPHYSICS

Back-arc basin processes

Continental shelf and slope processes (4219)

Gas and hydrate systems

Marine magnetics and paleomagnetics (1550)

Marine electromagnetics

Gravity and isostasy (1218, 1222)

Heat flow (benthic)

Hydrothermal systems (0450, 1034, 3616, 4832, 8135, 8424)

Littoral processes

Marine hydrogeology

Marine sediments: processes and transport

Marine seismics (0935, 7294)

Micropaleontology (0459, 4944)

Midocean ridge processes

Ocean drilling

Oceanic hotspots and intraplate volcanism

Oceanic plateaus and microcontinents

Oceanic transform and fracture zone processes

Plate tectonics (8150, 8155, 8157, 8158)

Ophiolites (8140)

Seafloor morphology, geology, and geophysics

Ocean observatories and experiments

Subduction zone processes (1031, 3613, 8170, 8413)

Submarine landslides

Submarine tectonics and volcanism

Submergence instruments: ROV, AUV, submersibles

Instruments and techniques

General or miscellaneous

MATHEMATICAL GEOPHYSICS (0500, 4307, 4314, 4400, 7833)

Fourier analysis (3255)

Instability analysis (4312)

Inverse theory

Numerical approximations and analysis (4260)

Persistence, memory, correlations, clustering (3265, 4313, 7857)

Prediction (3245, 4263, 4315)

Probabilistic forecasting (3238, 4315)

Spatial analysis (0500, 1980, 4319)

Spectral analysis (3205, 3280, 4319)

Stochastic processes (3235, 4468, 4475, 7857)

Time series analysis (1872, 1988, 4277, 4475)

Uncertainty quantification (1873, 1990)

Wavelet transform (3255, 4455)

Wave propagation (0689, 2487, 4275, 4455, 6934)

Instruments and techniques

General or miscellaneous

ATMOSPHERIC PROCESSES

Atmospheric electricity

Balanced dynamical models

Climate change and variability (1616, 1635, 3309, 4215, 4513)

Boundary layer processes

Climatology (1616, 1620, 3305, 4215, 8408)

Clouds and aerosols

Clouds and cloud feedbacks

Convective processes

Data assimilation

General circulation (1223)

Idealized model

Land/atmosphere interactions (1218, 1631, 1843, 4301)

Large eddy simulation

Lightning

Monte Carlo technique

Mesoscale meteorology

Mesospheric dynamics

Model calibration (1846)

Middle atmosphere dynamics (0341, 0342)

North American Monsoon

Numerical approximations and analyses (1849)

Global climate models (1626, 4928)

Ocean/atmosphere interactions (0312, 4301, 4504)

Paleoclimatology (0473, 4900)

Planetary meteorology (5445, 5739)

Polar meteorology

Precipitation (1854)

Radiative processes

Regional modeling (4316)

Remote sensing (4337)

Stratosphere/troposphere interactions

Stratospheric dynamics

Synoptic-scale meteorology

Subgrid-scale (SGS) parameterization

Theoretical modeling (4316)

Thermospheric dynamics (0358)

Tropical convection

Tropical cyclones

Tropical dynamics

Tropical meteorology

Tropopause dynamics

Turbulence (4490)

Acoustic-gravity waves

Tides and planetary waves

Wildland fire model

Instruments and techniques

General or miscellaneous

MINERALOGY AND PETROLOGY

Geochemical modeling (1009, 8410)

Thermodynamics (0766, 1011, 8411)

Reactions and phase equilibria (1012, 8412)

Subduction zone processes (1031, 3060, 8170, 8413)

Mid-oceanic ridge processes (1032, 8416)

Intra-plate processes (1033, 8415)

Hydrothermal systems (0450, 1034, 3017, 4832, 8135, 8424)

Alteration and weathering processes (1039)

Magma chamber processes (1036)

Magma genesis and partial melting (1037)

Mantle processes (1038)

Mineral and crystal chemistry (1042)

Petrography, microstructures, and textures

Experimental mineralogy and petrology

Igneous petrology

Extrusive structures and rocks

Intrusive structures and rocks

Layered magma chambers

Metamorphic petrology

Thermobarometry

Pressure-temperature-time paths

Fluid flow

Ultra-high pressure metamorphism

Ultra-high temperature metamorphism

Meteorite mineralogy and petrology (1028, 6240)

Mineral occurrences and deposits

Planetary mineralogy and petrology (5410)

Sedimentary petrology

Field relationships (1090, 8486)

Instruments and techniques

General or miscellaneous

MINERAL PHYSICS

Creep and deformation

Defects

Elasticity and anelasticity

Electrical properties

Equations of state

High-pressure behavior

NMR, Mossbauer spectroscopy, and other magnetic techniques

Optical, infrared, and Raman spectroscopy

Physical thermodynamics

Shock wave experiments

Surfaces and interfaces

Thermal expansivity

X-ray, neutron, and electron spectroscopy and diffraction

Instruments and techniques

General or miscellaneous

NATURAL HAZARDS

Atmospheric (0370 3322, 3339)

Geological (0742, 4564, 7212, 7280, 8419, 8425, 8426, 8428, 8488)

Hydrological (1810, 1812, 1821)

Oceanic (1641, 4564)

Space weather (2101, 2788, 7900)

Multihazards

Methods (0500, 3200, 4400)

Other (0468, 0702, 6205, 6210)

Analogue modeling

Catastrophe and catastrophe theory (3215)

Extreme events (1817, 3235)

Mathematical and computer modeling (0500, 3200)

Monitoring, forecasting, prediction (1816, 1922, 2722, 3238, 3245, 4263, 7223, 7924)

Physical modeling (0466, 0545, 0798, 1622, 1847, 1952, 3355, 3367)

Precursors

Statistical analysis (1984, 1986)

Spatial modeling (3252, 3255)

Climate impact (1630, 1637, 1807, 8408)

Health impact

Human impact (1834, 7938)

Spatial decision support systems (1918, 6309)

Megacities and urban environment (0345, 0478, 0493)

Exposure

Resilience

Risk (8488)

Sustainable development

Vulnerability

Disaster relief

Disaster resilience

Disaster risk analysis and assessment (6304, 8488)

Disaster risk communication

Disaster management

Economic impacts of disasters

Remote sensing and disasters (1243, 1640, 1855, 3360, 8485)

Disaster policy (6300, 6620)

Disaster mitigation (6309, 7914)

Early warning systems

Emergency management (6344)

Preparedness and planning (6334)

Microzonation and macrozonation

Community management

Emergency response and evacuations (1964)

Recovery and reconstruction after disaster

Contingency planning

International organizations and natural disasters

Interaction between science and disaster management authorities

Sociology of disasters (1974)

Psychology of disasters

Miscellaneous

NONLINEAR GEOPHYSICS (3200, 4307, 6944, 7839)

Bifurcations and attractors

Cascades

Chaos (7805)

Critical phenomena

Complex systems

Emergent phenomena

Fractals and multifractals

Nonlinear differential equations

Nonlinear maps

Nonlinear waves, shock waves, solitons (0689, 2487, 3280, 3285, 4275, 6934, 7851, 7852)

Pattern formation

Phase transitions

Probability distributions, heavy and fat-tailed (3265)

Renormalization group methods

Scaling: spatial and temporal (1872, 1988, 3265, 3270, 4277, 7857)

Self-organized criticality

Self-organization

Turbulence (3379, 4568, 7863)

Instruments and techniques

General or miscellaneous

OCEANOGRAPHY: GENERAL

Analytical modeling and laboratory experiments

Arctic and Antarctic oceanography (9310, 9315)

Benthic boundary layers

Climate and interannual variability (1616, 1635, 3305, 3309, 4513)

Coastal processes

Continental shelf and slope processes (3002)

Coral reef systems (4916)

Descriptive and regional oceanography

Diurnal, seasonal, and annual cycles (0438)

Equatorial oceanography

Estuarine processes (0442)

Limnology (0458, 1845, 4942)

Marginal and semi-enclosed seas

Marine meteorology

Marine pollution (0345, 0478)

Numerical modeling (0545, 0560, 1952)

Ocean acoustics

Ocean data assimilation and reanalysis (3225)

Ocean observing systems

Ocean predictability and prediction (3238, 4315)

Ocean optics (0649)

Physical and chemical properties of seawater

Physical and biogeochemical interactions

Remote sensing and electromagnetic processes (0689, 2487, 3285, 4455, 6934)

Time series experiments (1872, 1988, 3270, 4475)

Upwelling and convergences (4964)

Water masses

Instruments and techniques

General or miscellaneous

OCEANOGRAPHY: PHYSICAL

Air/sea interactions (0312, 3339)

Capillary waves

Coriolis effects

Currents

Decadal ocean variability (1616, 1635, 3305, 4215)

Deep recirculations

Eastern boundary currents

Eddies and mesoscale processes

ENSO (4922)

Fine structure and microstructure

Fronts and jets

General circulation (1218, 1222)

Hydrodynamic modeling

Hydrography and tracers

Ice mechanics and air/sea/ice exchange processes (0700, 0750, 0752, 0754)

Internal and inertial waves

Nearshore processes

Ocean fog

Ocean influence of Earth rotation (1223)

Overflows

Planetary waves

Sea level: variations and mean (1222, 1225, 1641)

Sediment transport (1862)

Surface waves and tides (1222)

Topographic/bathymetric interactions

Tsunamis and storm surges (4302, 4304)

Turbulence, diffusion, and mixing processes (4490)

Upper ocean and mixed layer processes

Western boundary currents

Instruments and techniques

General or miscellaneous

OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL (0460)

Aerosols (0305, 4906)

Analytical chemistry

Anoxic environments (0404, 1803, 4834, 4902)

Benthic processes, benthos (0408)

Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 1615, 4912)

Carbon cycling (0428)

Chemical speciation and complexation

Chemical tracers

Chemosynthesis

Colloids

Ecological prediction

Ecosystems, structure, dynamics, and modeling (0439)

Food webs, structure, and dynamics (0491)

Gases

Geochemistry

Higher trophic levels

Hydrothermal systems (0450, 1034, 3017, 3616, 8135, 8424)

Hypoxic environments (0404, 4802)

Marine inorganic chemistry (1050)

Microbiology and microbial ecology (0465)

Natural products chemistry

Nutrients and nutrient cycling (0470, 1050)

Marine organic chemistry (0470, 1050)

Oxidation/reduction reactions (0471)

Photochemistry

Photosynthesis

Physical chemistry

Phytoplankton

Population dynamics and ecology

Radioactivity and radioisotopes

Sedimentation (1861)

Sorptive scavenging

Stable isotopes (0454, 1041)

Symbiosis

Trace elements (0489)

Zooplankton

Instruments, sensors, and techniques

General or miscellaneous

PALEOCEANOGRAPHY (0473, 3344)

Abrupt/rapid climate change (1605)

Anthropogenic effects (1803, 4802)

Atmospheric transport and circulation

Aerosols (0305, 4801)

Albedo

Astronomical forcing

Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 1615, 4805)

Continental climate records

Corals (4220)

Cosmogenic isotopes (1150)

Dendrochronology

El Nino (4522)

Geochemical tracers

Glacial

Global climate models (1626, 3337)

Greenhouse gases

Ice cores (0724)

Insolation forcing

Interglacial

Interhemispheric phasing

Isotopic stage

Limnology (0458, 1845, 4239)

Micropaleontology (0459, 3030)

Milankovitch theory

Paleocene/Eocene thermal maximum

Paleoecology

Palynology

Sea surface temperature

Speleothems

Stadial

Thermohaline

Upwelling (4279)

Instruments and techniques

General or miscellaneous

PHYSICAL PROPERTIES OF ROCKS

Acoustic properties

Fracture and flow

Magnetic and electrical properties (0925)

Microstructure

Permeability and porosity

Plasticity, diffusion, and creep

Thermal properties

Transport properties

Wave attenuation

Instruments and techniques

General or miscellaneous

PLANETARY SCIENCES: ASTROBIOLOGY

Formation of stars and planets

Planetary atmospheres, clouds, and hazes (0343)

Origin of life

Hydrothermal systems and weathering on other planets

Early environment of Earth

PLANETARY SCIENCES: SOLID SURFACE PLANETS

Atmospheres (0343, 1060)

Aurorae and airglow

Composition (1060, 3672)

Erosion and weathering

Glaciation

Gravitational fields (1221)

Heat flow

Hydrology and fluvial processes

Ices

Impact phenomena, cratering (6022, 8136)

Interactions with particles and fields

Interiors (8147)

Ionospheres (2459)

Magnetic fields and magnetism

Magnetospheres (2756)

Meteorology (3346)

Orbital and rotational dynamics (1221)

Origin and evolution

Physical properties of materials

Polar regions

Remote sensing

Rings and dust

Surface materials and properties

Tectonics (8149)

Volcanism (6063, 8148, 8450)

Instruments and techniques

General or miscellaneous

PLANETARY SCIENCES: FLUID PLANETS

Atmospheres (0343, 1060)

Aurorae

Composition (1060)

Gravitational fields (1221)

Interactions with particles and fields

Interiors (8147)

Ionospheres (2459)

Magnetic fields and magnetism

Magnetospheres (2756)

Meteorology (3346)

Orbital and rotational dynamics (1221)

Origin and evolution

Polar regions

Rings and dust

Tidal forces

Tori and exospheres

Instruments and techniques

General or miscellaneous

PLANETARY SCIENCES: COMETS AND SMALL BODIES

Atmospheres (1060)

Aurorae, airglow, and X-ray emission

Composition (1060)

Dust

Erosion and weathering

Gravitational fields (1221)

Ices

Impact phenomena (5420, 8136)

Interactions with solar wind plasma and fields

Comets: dust tails and trails (6210)

Interiors (8147)

Ionospheres (2459)

Magnetic fields and magnetism

Magnetospheres (2756)

Orbital and rotational dynamics

Origin and evolution

Physics and chemistry of materials

Plasma and MHD instabilities (2149, 2752, 7836)

Surfaces

Radiation and chemistry

Volcanism (5480, 8450)

Instruments and techniques

General or miscellaneous

PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS

Asteroids (4308)

Asteroids: satellites

Comparative planetology

Comets (4308, 6023)

Centaurs

Dust

Jovian satellites

Io

Europa

Ganymede

Callisto

Jupiter

Kuiper belt objects

Mars

Martian satellites

Mercury

Meteorites and tektites (1028, 3662)

Meteors

Moon (1221)

Neptune

Neptunian satellites

Triton

Planetary rings

Pluto and satellites

Saturn

Saturnian satellites

Titan

Enceladus

Trans-Neptunian objects

Uranian satellites

Uranus

Venus

Extra-solar planets

Instruments and techniques

General or miscellaneous

POLICY SCIENCES (4338, 7964)

Benefit-cost analysis (4333)

Decision making under uncertainty (1918, 4324, 4339)

Demand estimation

Institutions

Legislation and regulations (6615)

Project evaluation

Regional planning (1880, 4343)

System design

System operation and management (4342)

General or miscellaneous

PUBLIC ISSUES

Funding

Legislation and regulations (6324)

Science policy (0485, 4338)

Workforce

General or miscellaneous

RADIO SCIENCE

Electromagnetic noise and interference

Interferometry (1207, 1209, 1242)

Ionospheric physics (1240, 2400)

Ionospheric propagation (0689, 2487, 3285, 4275, 4455)

Magnetospheric physics (2700)

Nonlinear phenomena (4400, 7839)

Radar astronomy

Radar atmospheric physics (1220)

Radio astronomy

Radio oceanography (1222)

Radio wave propagation

Remote sensing

Signal processing (0674)

Space and satellite communication

Tomography and imaging (7270, 8180)

Waves in plasma (7867)

Instruments and techniques (1241)

General or miscellaneous

SEISMOLOGY

Body waves

Continental crust (1219)

Core (1212, 1213, 8124)

Mantle (1212, 1213, 8124)

Earthquake dynamics (1242)

Earthquake ground motions and engineering seismology (4302)

Earthquake source observations (1240)

Lithosphere (1236)

Seismic monitoring and test-ban treaty verification

Oceanic crust

Paleoseismology (8036)

Earthquake interaction, forecasting, and prediction (1217, 1242, 4315)

Seismicity and tectonics (1207, 1217, 1240, 1242)

Subduction zones (1207, 1219, 1240)

Mid-ocean ridges

Transform faults

Surface waves and free oscillations

Theory

Tomography (6982, 8180)

Volcano seismology (4302, 8419)

Computational seismology

Seismic instruments and networks (0935, 3025)

General or miscellaneous

SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY

Celestial mechanics

Chromosphere

Corona

Coronal holes

Coronal mass ejections (2101)

Energetic particles (2114)

Flares

Helioseismology

Magnetic fields

Magnetic reconnection (2723, 7835)

Photosphere

Prominence eruptions

Radio emissions

Solar activity cycle (2162)

Solar and stellar variability (1650)

Solar irradiance

Stellar astronomy

Stellar interiors and dynamo theory

Transition region

Ultraviolet emissions

X-rays, gamma rays, and neutrinos

Instruments and techniques

General or miscellaneous

SPACE PLASMA PHYSICS

Active perturbation experiments

Chaos (4420)

Charged particle motion and acceleration

Discontinuities (2109)

Electrostatic structures

Ionization processes (2423)

Kinetic and MHD theory

Kinetic waves and instabilities

Laboratory studies and experimental techniques

Magnetic reconnection (2723, 7526)

Mathematical and numerical techniques (0500, 3200)

MHD waves and instabilities (2149, 2752, 6050)

Neutral particles (2151)

Nonlinear phenomena (4400, 6944)

Parametric processes

Particle acceleration

Plasma energization

Plasma interactions with dust and aerosols (2461)

Radiation processes

Shock waves (4455)

Solitons and solitary waves (4455)

Spacecraft/atmosphere interactions

Spacecraft sheaths, wakes, charging

Stochastic phenomena (3235, 3265, 4475)

Transport processes

Turbulence (4490)

Wave/particle interactions (2483, 6984)

Wave/wave interactions

Instruments and techniques

General or miscellaneous

SPACE WEATHER (4305)

Geomagnetically induced currents

Engineering for hazard mitigation (4339)

Forecasting (1922, 2722, 4315)

Impacts on technological systems

Impacts on humans (4323)

Ionospheric effects on radio waves

Ionospheric storms (2441)

Magnetic storms (2788)

Models

Policy (2722, 6300)

Satellite drag (1241)

Solar effects

Space radiation environment

General or miscellaneous

STRUCTURAL GEOLOGY

Continental neotectonics (8107)

Diapir and diapirism

Dynamics and mechanics of faulting (8118)

Folds and folding

Fractures and faults

Kinematics of crustal and mantle deformation

High strain deformation zones

Local crustal structure

Mechanics, theory, and modeling

Melanges

Mesoscopic fabrics

Microstructures

Rheology: crust and lithosphere (8159)

Rheology: general (8160)

Rheology: mantle (8162)

Rheology and friction of fault zones (8163)

Pluton emplacement

Paleoseismology (7221)

Regional crustal structure

Remote sensing

Role of fluids

Instruments and techniques

General or miscellaneous

TECTONOPHYSICS

Continental contractional orogenic belts and inversion tectonics

Continental cratons

Continental margins: convergent

Continental margins: divergent (1212, 8124)

Continental margins: transform

Continental neotectonics (8002)

Continental tectonics: compressional

Continental tectonics: extensional (0905)

Continental tectonics: general (0905)

Continental tectonics: strike-slip and transform

Core processes (1213, 1507)

Dynamics and mechanics of faulting (8004)

Dynamics of lithosphere and mantle: general (1213)

Dynamics: convection currents, and mantle plumes

Dynamics: gravity and tectonics

Dynamics: seismotectonics

Earth's interior: composition and state (1212, 7207, 7208, 8105)

Evolution of the Earth (0325)

Heat generation and transport

Hydrothermal systems (0450, 1034, 3017, 3616, 4832, 8424)

Impact phenomena (5420, 6022)

Hotspots, large igneous provinces, and flood basalt volcanism

Lithospheric flexure

Obduction tectonics

Ophiolites (3042)

Physics of magma and magma bodies

Planetary interiors (5430, 5724, 6024)

Planetary volcanism (5480, 8450)

Planetary tectonics (5475)

Plate boundary: general (3040)

Plate motions: general (3040)

Plate motions: past (3040)

Plate motions: present and recent (3040)

Rheology: crust and lithosphere (8031)

Rheology: general (1236, 8032)

Rheology: mantle (8033)

Rheology and friction of fault zones (8034)

Stresses: crust and lithosphere

Stresses: deep-seated

Stresses: general

Sedimentary basin processes

Subduction zone processes (1031, 3060, 3613, 8413)

Tectonics and landscape evolution

Tectonics and climatic interactions

Tectonics and magmatism

Tomography (6982, 7270)

Volcanic arcs

Instruments and techniques

General or miscellaneous

VOLCANOLOGY

Geochemical modeling (1009, 3610)

Thermodynamics (0766, 1011, 3611)

Reactions and phase equilibria (1012, 3612)

Subduction zone processes (1031, 3060, 3613, 8170)

Mid-oceanic ridge processes (1032, 3614)

Intra-plate processes (1033, 3615)

Hydrothermal systems (0450, 1034, 3017, 3616, 4832, 8135)

Effusive volcanism (4302)

Mud volcanism (4302)

Subaqueous volcanism

Explosive volcanism (4302)

Planetary volcanism (5480, 6063, 8148)

Volcanoclastic deposits

Volcano/climate interactions (1605, 3309, 4321)

Atmospheric effects (0370)

Volcanic gases

Lava rheology and morphology

Magma migration and fragmentation

Eruption mechanisms and flow emplacement

Physics and chemistry of magma bodies

Calderas

Experimental volcanism

Tephrochronology (1145)

Remote sensing of volcanoes (4337)

Field relationships (1090, 3690)

Volcano monitoring (4302, 7280)

Volcanic hazards and risks (4302, 4328, 4333)

Instruments and techniques

General or miscellaneous

GEOGRAPHIC LOCATION

Africa

Antarctica (4207)

Arctic region (0718, 4207)

Asia

Atlantic Ocean

Australia

Europe

Indian Ocean

Large bodies of water (e.g., lakes and inland seas) (0746)

North America

Pacific Ocean

South America

General or miscellaneous

INFORMATION RELATED TO GEOLOGIC TIME

Cenozoic

Neogene

Paleogene

Mesozoic

Cretaceous

Jurassic

Triassic

Paleozoic

Permian

Carboniferous

Devonian

Silurian

Ordovician

Cambrian

Precambrian

Proterozoic

Archean

General or miscellaneous

GENERAL OR MISCELLANEOUS

Instruments useful in three or more fields

New fields (not classifiable under other headings)

Notices and announcements

Techniques applicable in three or more fields