PDF reasons why Geomorphology - IAG/AIG

10 reasonswhy

Geomorphology

isimportant

BSG

BritishSocietyforGeomorphology

10 reasonswhy

Geomorphology

isimportant

preparedbyStephenToothandHeatherViles,withinputfrom theBritishSocietyforGeomorphologyExecutiveCommittee

photographeracknowledgmentsareprovidedinthefigurecaptions figuresbyAntonySmithatAberystwythUniversity layoutbyChrisSimpsonatFulcrumGraphics

.uk

registeredcharity1054260

Whatisgeomorphology?

Intoday'sworld,thereismuchinterestin,andconcernabout, theglobalenvironmentandhowitoperatesandchanges.The threats of climate change and species extinctions are commonlyhighlighted,butwhataboutthepotentialchanges to physical landscapes? Understanding how landscapes operate and change is a crucial part of gaining a full understanding of the Earth system and enabling better environmentalmanagement. Therearemanyquestionsthat remain to be answered about physical landscapes and our interactionswiththem.

? WhyaresomepartsoftheEarthmountainousandother partsmuchflatter?

? WhyaretheHimalayasohigh? ? WhydoespartoftheAustraliancontinentalinteriorlieclose

to,orbelow,sealevel?

? WheredoesallthesandintheSaharacomefrom? ? HowoldistheGrandCanyon? ? HowfastareGreenland'sglaciersretreating? ? How rapidly will Britain's coastline change over the 21st

centurywithpredictedrisesinsealevel?

? Arehazardslikelandslidesgettingmoreserious? ? Howcanwebestconserveandmanagelandscapes?

Geomorphology is the science that studies the origin and development of landforms (such as hills, valleys, sand dunes, caves),andhowthoselandformscombinetoformlandscapes. Assuch,itmakesacriticalcontributiontoansweringthesortsof aforementionedquestions.Geomorphologicalstudiesinclude thequantitativeanalysisoflandformshapes,themonitoringof surface and near-surface processes (e.g. running water, ice, wind) that shape landforms, and the characterisation of landform changes that occur in response to factors such as tectonicandvolcanicactivity,climateandsealevelchange,and human activities. Investigations may be directed principally towardsreconstructingpastprocessesandlandformchanges, towards understanding present-day processes and landform changes,ortowardsanticipatingfutureprocessesandlandform changes.

geomorphology

ge -'earth morphe -'form logos-'discourse

Howaregeomorphologicalstudiesundertaken?

Geomorphologyisaneclecticsciencethathasitsownheritage available(Figure1b),andground-basedmonitoring,compuand history but also draws on aspects of other sciences, tationalmodelling,andgeochronological(dating)techniques particularly physical geography, geology, and ecology. (e.g. luminescence, cosmogenic isotope analysis) have Traditionally, geomorphological study approaches focused advanced rapidly. Consequently, traditional geomormainlyonfieldobservation,descriptionandmeasurementbut phologicalstudy approachesare now commonlycombined alsoincludedphysicalexperimentation(e.g.insmallfieldplots with these new images, models and techniquesto quantify orusinglaboratoryflumes). Sincetheearly1970s,however, ratesandtimescalesoflandformchange.Itisnowpossibleto high-resolutionimagesofthesurfacetopographyoftheEarth view, measure, age, and model a variety of landforms and and other planetshave been acquiredat rapid pace from a landscapes in ways that were unimaginable even a decade variety of satellitesand spacecraft(e.g. Figure 1a). Many of ago.Theseadvancesarehelpingtoshedlightonavarietyof these images are now readily available for free from the long-standingproblemsinexplainingthedevelopmentofthe internet(e.g. using virtual globes such as Google Earth). In Earth's surface, as well as informing interpretation of the addition, large numbers of computer-based topographic developmentofotherplanetarysurfaces(mostnotablyMars). models (e.g. Digital Elevation Models) have become readily

a

b

0

10km

0

2km

Figure 1. a) Widespread availability of satellite imagery such as this Landsat image of the multiple channels of the Ob River, Russia, enables parisonofsatelliteimagesfromdifferentdatesenablesassessmentofratesofriverine andwiderlandscapechange(Source:UnitedStatesGeologicalSurveyEarthExplorer).b)AhighresolutionDigitalElevationModelofameander bendontheMississippiRiver,USA,canbeusedtoidentifysedimentdepositionzonesandmeasuremovementpatterns.Inthisinstance,the curvedfeaturesontheinsideofthebendareformerchanneldepositsandindicatebendmigrationtowardsthelowerleftoftheimage(Source: Atlas:TheLouisianaStatewideGIS).

BritishSocietyforGeomorphology-10reasonswhyGeomorphologyisimportant

1

Whyisgeomorphologyimportant?

Inadditiontoexplaininghowlandscapeshavedevelopedinthe past,howtheyfunctionatpresent,andhowtheymightchange in future, there is growing recognition of the importance of geomorphology and geomorphologists in contributing to a rangeofenvironmentalinvestigationsandmanagementissues (Figure2).

phologicalprocessesprovidethemorphological,sedimentary, and hydrological templates upon which key ecological processessuchassuccessiontakeplace;inparticular,ecologists concerned with conservation of biodiversity are interested in understanding the complexity of the physical landscape - 'geodiversity' - as this can exert an important control over species diversity. Implicitly or explicitly, geomorphological

Environmental policyand

management

Global change

Geology: structuraland

petroleum

Planetary science

Geomorphology

Environmental engineering

Ecology

Archaeology

Figure2.Geomorphologyinterfaceswith,andcontributesto,many differentaspectsoftheearth,environmentalandsocialsciences.

Forinstance,structuralgeologistswanttoknowhowerosionat the Earth's surface influences patterns of rock deformation in developingmountainbelts. Petroleumgeologistsemployan understanding of modern-day depositional processes to improvesubsurfaceexplorationeffortsforoilandgasreserves hosted in sedimentary rocks. Engineers use knowledge of erosionalanddepositionalprocessestoimproveestimationsof the thresholds of stability for hillslopes, or to assess the likelihoodofchannelchangesalongriverswhereinfrastructural developmentsareplanned. Planetaryscientistsapplyinsights gained from study of the Earth's landscape processes to help theminterpretplanetarysurfaces.Archaeologistsareinterested in how erosional and depositional processes influence the preservationofartefactsandotherformsofevidenceforpast human societies. Ecologists acknowledge that geomor-

considerations also underpin many aspects of environmental policy,law,andlandmanagementdecisionmaking,suchasthe EuropeanUnion'sWaterFrameworkDirective.

Inshort,geomorphologyandgeomorphologistsprovidedata, knowledge and perspectives that are additional and complementary to those provided by other academic disciplinesandprofessions. Inmanycases,geomorphological considerationsareimportantindeedessentialforenablinga comprehensiveapproachtoenvironmentalinvestigationsand achievingsustainableenvironmentalmanagement.

Whatisthisdocumentabout?

Despitethedemonstrableimportanceofgeomorphology,the Nonetheless, there are a large number of national and terms 'geomorphology' and 'geomorphologist' are probably international organizations dedicated to the support and not very well understood. In part, this is because promotionofgeomorphology,includingtheBritishSocietyfor geomorphology does not exist as a stand-alone university Geomorphology (BSG), the Australian and New Zealand discipline, typically having its roots within Geography Geomorphology Group (ANZGG), and the International departmentsincountriesliketheUKandAustraliaandmainly AssociationofGeomorphologists(IAG). Inaddition,specialist within Geology or Earth Science departments in the USA. geomorphology sessions are regularly held within meetings

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BritishSocietyforGeomorphology-10reasonswhyGeomorphologyisimportant

convened by larger organizations such as the European Geosciences Union (EGU) or American Geophysical Union (AGU).

The aim of this document is to introduce the term 'geomorphology'toanon-specialistaudienceandtoillustratea selection of key principles that underpin the discipline. The popularityofvirtualglobessuchasGoogleEarthillustratesthat publicinterestinthelandformsandlandscapesoftheEarthand other planetary bodies is high; some of the online discussion threads in Google Earth Blog and Google Earth Community forums even revolve around questions of landform development, but in some cases the accuracy and clarity of discussion could benefit from greater grounding in the

principles of modern geomorphology. Drawing inspiration fromtheUS-basedClimateLiteracy1andEarthScienceLiteracy initiatives2,wehighlighttenkeypointsthatanycitizenshould know about geomorphology. These ten points are not exhaustive but are simply intended to indicate why geomorphologyshouldbeviewedasaneclecticbutcoherent, vibrant, innovative and relevant science. The document concludesbyprovidingsourcesofadditionalinformation.

1resources/educators/climate-literacy 2

Geomorphicliteracy:10keypointsthat everyoneshouldknowaboutgeomorphology

Thetenkeypointsthateveryoneshouldknowaboutgeomorphology-thetenreasonswhygeomorphologyisimportant-are summarizedinTable1,bothinabridgedandextendedform.

Table1.Summaryofthetenkeypoints

Landscapesareshapedby

1 movementsofmass

Landscapeshapingprocesses

2 areinfluencedbymany differentfactors Landscapeprocessesoperate

3 atmanydifferentscales

TheEarth'slandscapes

4 aredynamic

Landformsareshapedbygeomorphologicalprocesses,whichessentially involvethemovementofmassrock,sediment,wateracrosstheEarth's surface

Varioustectonic,geological,climaticandecologicalfactorsprovidemajor influencesongeomorphologicalprocessesandthemovementofmass

Thetectonic,geological,climaticandecologicalfactorsthatinfluence geomorphologicalprocessesandmovementofmasschangewithdifferent timeandspacescales

Landformsandlandscapesarenotstaticandunchanging,butaredynamic anddevelopthroughtime

Landscapedynamicsare

5 oftencomplex

Inadditiontochangingtectonic,geological,climaticorecologicalconditions, internalreadjustmentscanalsodrivelandformandlandscapedevelopment

Landscapesarearchives

6 ofthepast

Globalchangeisinfluencing

7 landscapedynamics

Humanactivitiesare

8 influencinglandscape

dynamics TheEarth'slandscapesare

9 becomingmorehazardous

Successfulenvironmental

10 managementneeds geomorphologicalknowledge

Landscapescontainhistoriesoftheirdevelopmentthatpotentiallycanbe decipheredandreconstructedfromstudyoftheassociatedlandformsand sediments

Ongoingglobalenvironmentalchange,whichincludesatmosphericwarming andsealevelrise,iscurrentlydrivinglandformdevelopment,includingdesert lakedesiccation,icesheetandglacialretreat,andcoastlineerosion

Increasingly,manygeomorphologicalprocessesandlandform/landscape developmentsareinfluencedbyhumanactivities

Bothglobalenvironmentalchangeandhumanactivitiesareincreasingthe magnitudeandfrequencyofgeomorphologicalhazards,whichoccur whereverandwheneverlandsurfacestabilityisaffectedandadversesocioeconomicimpactsareexperienced

Geomorphologycanprovideakeyinputtoenvironmentalmanagement, includinglandscapeconservation,ecosystemconservationandrestoration, heritageconservationandcarbonlandscaping

BritishSocietyforGeomorphology-10reasonswhyGeomorphologyisimportant

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