If increasingly globalized societies are to make better land management decisions, the geosciences must globally evaluate how humans are reshaping Earth 's surface</jats:p

Ellis, E. C.

Sofia, G.

Tarolli, P.

English

Paolo Tarolli

Giulia Sofia

Erle Ellis

Crossref

Mapping the Topographic Fingerprints of Humanity Across Earth

Tarolli P.

Sofia G.

Ellis E. C.

Archivio istituzionale della ricerca - Università di Padova

Original Citation:Mapping the topographic fingerprints of humanity across EarthPublisher:Published version:DOI:Terms of use:Open Access(Article begins on next page)This article is made available under terms and conditions applicable to Open Access Guidelines, as described athttp://www.unipd.it/download/file/fid/55401 (Italian only)Availability:This version is available at: 11577/3257934 since: 2018-02-19T00:12:13Z10.1029/2017EO069637Università degli Studi di PadovaPadua Research Archive - Institutional RepositoryEarth & Space Science News Eos.org  //  13OPINIONS ince geologic time began, Earth’s sur-face has been evolving through natural processes of tectonic uplift, volcanism, erosion, and the movement of sediment. Now a new force of global change is altering Earth’s surface and morphology in unprecedented ways: humanity.Human activities are leaving their finger-prints across Earth (Figure 1), driven by increasing populations, technological capaci-ties, and societal demands [e.g., Ellis, 2015; Brown et al., 2017; Waters et al., 2016]. We have altered flood patterns, created barriers to runoff and erosion, funneled sedimentation into specific areas, flattened mountains, piled hills, dredged land from the sea, and even triggered seismic activity [Tarolli and Sofia, 2016]. These and other changes can pose broad threats to the sustainability of human societies and  environments.If increasingly globalized societies are to make better land management decisions, the geosciences must globally evaluate how humans are reshaping Earth’s surface. A comprehensive mapping of human  topographic signatures on a  planet- wide scale is required if we are to understand, model, and forecast the geological hazards of the future.Understanding and addressing the causes and consequences of anthropogenic landform modifications are a worldwide challenge. But this challenge also poses an opportunity to better manage environmental resources and protect environmental values [DeFries et al., 2012].The Challenge of Three Dimensions“If life happens in three dimensions, why doesn’t science?” This question, posed more than a decade ago in Nature [Butler, 2006], res-onates when assessing human reshaping of Earth’s landscapes.Landforms are shaped in three dimensions by natural processes and societal demands [e.g., Sidle and Ziegler, 2012; Guthrie, 2015]; societies in turn are shaped by the landscapes they alter. Understanding and modeling these interacting forces across Earth are not small challenges.For example, observing and modeling the direct effects of some of the most widespread forms of human topographic modification, such as soil tillage and terracing [Tarolli et al., 2014], are possible only with very fine spatial resolutions (i.e., ≤1 meter). Yet these features are common all over the world.  High-  resolution  three- dimensional topographic data at global scales are needed to observe and appraise them.The Need for a Unified, Global Topographic Data Set High- resolution terrain data such as lidar [Tarolli, 2014], aerial photogrammetry [Eltner et al., 2016], and satellite observations [Fami-glietti et al., 2015] are increasingly available to the scientific community. These data sets are also becoming available to land planners and the public, as governments, academic institu-tions, and others in the remote sensing com-munity seize the opportunity for  high-  resolution topographic data sharing (Figure 2) [Wulder and Coops, 2014; Verburg et al., 2015].Thanks to these geodata, anthropogenic signatures are widely observable across the globe, under vegetation cover (Figure 2a), at very fine spatial scales (e.g., agricultural prac-Mapping the Topographic Fingerprints of Humanity Across EarthFig. 1.  Three- dimensional view of Bingham Canyon Mine in Utah, a  human- made topographic signature, based on a free,  open- access  high- resolution data set. Credit: Data from Utah AGRC14  //  Eos November 2017OPINIONtices and plowing; Figure 2b) and large spatial scales (e.g., major open-pit mines; Figure 3), and far from contemporary human settle-ments (Figure 2c). So the potential to assess the global topographic fingerprints of humanity using  high- resolution terrain data is a tantalizing prospect.However, despite a growing number of local projects at fine scales, a global data set remains nonetheless elusive. This lack of global data is largely the result of technical challenges to sharing very large data sets and issues of data ownership and permissions.But once a global database exists, advances in the technical capacity to handle and ana-lyze large data sets could be utilized to map anthropogenic signatures in detail (e.g., using a  close- range terrestrial laser scanner) and across larger areas (e.g., using satellite data). Together with geomorphic analyses, the potential is clear for an innovative, transfor-mative, and  global- scale assessment of the extent to which humans shape Earth’s land-scapes.For example,  fine- scale analysis of terrain data can detect specific anthropogenic config-urations in the organization of surface fea-tures (Figure 3b) [Sofia et al., 2014], revealing modifications that humans make across land-scapes (Figure 3c). Such  fine- scale geomor-phic changes are generally invisible to coarser scales of observation and analysis, making it appear that natural landforms and natural hydrological and sedimentary processes are unaltered. Failure to observe such changes misrepresents the true extent and form of human modifications of terrain, with huge consequences when inaccurate data are used to assess risks to society from runoff, land-slides, and other geologic hazards [Tarolli, 2014].Topography  for SocietyA global map of the topographic signa-tures of humanity would create an unparalleled oppor-tunity to change sci-entific and public perspectives on the human role in reshaping Earth’s land surface. A worldwide inventory of anthropogenic geomorphologies would enable geosci-entists to assess the extent to which human societies have reshaped geomor-phic processes glob-ally and provide a tool for monitoring these changes over time.Such monitoring would facilitate unprece-dented insights into the dynamics and sensi-tivity of landscapes and their responses to human forcings at global scale. In turn, these insights would help cities, resource managers, and the public better understand and mediate their social and environmental actions.As we move deeper into the Anthropocene, a comprehensive mapping of human topo-graphic signatures will be increasingly neces-sary to understand, model, and forecast the geological hazards of the future. These haz-ards will likely be manifold.For example, landscapes across the world face altered flooding regimes in densely pop-ulated floodplains, erosion rates associated with road networks, altered runoff and ero-sion due to agricultural practices, and sedi-ment release and seismic activity from min-ing [Tarolli and Sofia, 2016]. Modifications in land use (e.g., urbanization and changes in agricultural practices) alter water infiltration and runoff production, increasing flooding risks in floodplains. Increases in road density cause land degradation and erosion, especially when roads are poorly planned and con-structed without  well- designed drainage sys-tems, leading to destabilized hillslopes and landslides. Erosion from agricultural fields can exceed rates of soil production, causing soil degradation and reducing crop yields, water quality, and food production. Mining areas, even years after reclamation, can induce seismicity, landslides, soil erosion, and terrain collapse, damaging environments and surface structures.Without accurate data on anthropogenic topography, communities will find it difficult to develop and implement strategies and practices aimed at reducing or mitigating the social and environmental impacts of anthro-pogenic geomorphic change.Earth Science Community’s Perspective NeededTechnological advances in Earth observa-tion have made possible what might have been inconceivable just a few years ago. A global map and inventory of human topo-graphic signatures in three dimensions at high spatial resolution can now become a reality.Collecting and broadening access to high spatial resolution (meter to submeter scale), Fig. 3. This potential detection of anthropogenic topographic signatures has been derived from satellite data. (a) This satellite image shows an  open- pit mine in North Korea. (b) This image has been processed in an autocorrelation anal-ysis, a measure of the organization of the topography (slope local length of autocorrelation, SLLAC [Sofia et al., 2014] ). The variation in the natural landscape is noisy (e.g., top right corner), whereas anthropogenic structures are more organized and leave a clear topographic signature. (c) The degree of landscape organization can be empirically related to the amount of  human- made alterations to the terrain, as demonstrated by Sofia et al. [2014]. Credit: Data from CNES© Distribution Airbus DSFig. 2.  High- resolution geodata reveal the topographic fingerprints of humanity: (a) ter-races in the Philippines, (b) agricultural practices in Germany, and (c) roads in Antarc-tica. The bottom images are lidar images of the same landscapes. Credit: Data from University of the Philippines TCAGP/Freie und Hansestadt Hamburg/Noh and Howat [2015]. Top row: © Google, DigitalGlobeEarth & Space Science News Eos.org  //  15OPINIONEarth  science– oriented topography data acquired with lidar and other technologies would promote scientific discovery while fostering international interactions and knowledge exchange across the Earth science community. At the same time, enlarging the search for humanity’s topographical finger-prints to the full spectrum of environmental and cultural settings across Earth’s surface will require a more generalized methodology for discovering and assessing these signa-tures.These two parallel needs are where scien-tific efforts should focus. It is time for the Earth science community to come together and bring the topographic fingerprints of humanity to the eyes and minds of the cur-rent and future stewards, shapers, curators, and managers of Earth’s land surface.AcknowledgmentsData sets for Figure 1 are from Utah Auto-mated Geographic Reference Center (AGRC), Geospatial Information Office. Data sets for Figures  2a– 2c are from the University of the Philippines Training Center for Applied Geodesy and Photogrammetry (TCAGP), Noh and Howat [2015], and Freie und Hansestadt Hamburg (from 2014), respectively. Data sets for Figure 3 are from Centre National d’Études Spatiales (CNES), France, Distribu-tion Airbus DS.ReferencesBrown, A. G., et al. (2017), The geomorphology of the Anthropo-cene: Emergence, status and implications, Earth Surf. Processes Landforms, 42,  71– 90, https:// doi . org/ 10 . 1002/ esp . 3943.Butler, D. (2006), Virtual globes: The  web- wide world, Nature, 439,  776– 778, https:// doi . org/ 10 . 1038/ 439776a.DeFries, R. S., et al. (2012), Planetary opportunities: A social con-tract for global change science to contribute to a sustainable future, BioScience, 62,  603– 606, https:// doi . org/ 10 . 1525/ bio . 2012 . 62 . 6 . 11.Ellis, E. C. (2015), Ecology in an anthropogenic biosphere, Ecol. Monogr., 85,  287– 331, https:// doi . org/ 10 . 1890/ 14 - 2274 . 1.Eltner, A., et al. (2016),  Image- based surface reconstruction in geo-morphometry—Merits, limits and developments, Earth Surf. Dyn., 4,  359– 389, https:// doi . org/ 10 . 5194/ esurf - 4 - 359 - 2016.Famiglietti, J. S., et al. (2015), Satellites provide the big picture, Science, 349,  684– 685, https:// doi . org/ 10 . 1126/ science . aac9238.Guthrie, R. (2015), The catastrophic nature of humans, Nat. Geosci., 8,  421– 422, https:// doi . org/ 10 . 1038/ ngeo2455.Noh, M. J., and I. M. Howat (2015), Automated  stereo-  photogrammetric DEM generation at high latitudes: Surface Extraction with  TIN- based  Search- space Minimization (SETSM) validation and demonstration over glaciated regions, GIScience Remote Sens., 52(2),  198– 217, https:// doi . org/ 10 . 1080/ 15481603 . 2015 . 1008621.Sidle, R. C., and A. D. Ziegler (2012), The dilemma of mountain roads, Nat. Geosci., 5,  437– 438, https:// doi . org/ 10 . 1038/ ngeo1512.Sofi a, G., F. Marinello, and P. Tarolli (2014), A new landscape metric for the identifi cation of terraced sites: The slope local length of  auto- correlation (SLLAC), ISPRS J. Photogramm. Remote Sens., 96,  123– 133, https:// doi . org/ 10 . 1016/ j . isprsjprs . 2014 . 06 . 018.Tarolli, P. (2014),  High- resolution topography for understanding Earth surface processes: Opportunities and challenges, Geomor-phology, 216,  295– 312, https:// doi . org/ 10 . 1016/ j . geomorph . 2014 . 03 . 008.Tarolli, P., and G. Sofi a (2016), Human topographic signatures and derived geomorphic processes across landscapes, Geomorphol-ogy, 255,  140– 161, https:// doi . org/ 10 . 1016/ j . geomorph . 2015 . 12 . 007.Tarolli, P., F. Preti, and N. Romano (2014), Terraced landscapes: From an old best practice to a potential hazard for soil degrada-tion due to land abandonment, Anthropocene, 6,  10– 25, https://  doi . org/ 10 . 1016/ j . ancene . 2014 . 03.002.Verburg, P. H., et al. (2015), Land system science and sustainable development of the Earth system: A global land project perspec-tive, Anthropocene, 12,  29– 41, https:// doi . org/ 10 . 1016/ j . ancene . 2015 . 09 . 004.Waters, C. N., et al. (2016), The Anthropocene is functionally and stratigraphically distinct from the Holocene, Science, 351, aad2622, https:// doi . org/ 10 . 1126/ science . aad2622.Wulder, M. A., and N. C. Coops (2014), Satellites: Make Earth observations open access, Nature, 513,  30– 31, https:// doi . org/ 10 . 1038/ 513030a.By Paolo Tarolli (email: paolo.tarolli @ unipd . it;  @ TarolliP) and Giulia Soﬁ a ( @ jubermensch2), Department of Land, Environment, Agriculture, and Forestry, University of Padova, Legnaro, Italy; and Erle Ellis ( @ erleellis), Department of Geography and Environmental Systems, University of Mary-land, Baltimore County, BaltimoreRead it first on Drone Peers into Open Volcanic Ventshttp://bit.ly/Eos_volcanic_vents A New Tool for Deep-Down Data Mininghttp://bit.ly/Eos_deep_data_mining Taking the Pulse of the Planethttp://bit.ly/Eos_planet_pulse Monitoring Ocean Change in the 21st Centuryhttp://bit.ly/Eos_monitoring_ocean_change World’s Biggest Oxygen Producers Livingin Swirling Ocean Watershttp://bit.ly/Eos_oxygen_producers Articles are published on Eos.org beforethey appear in the magazine.Visit https://eos.org daily for the latestnews and perspectives.

Mapping the topographic fingerprints of humanity across Earth

Padua Research Archive

https://www.research.unipd.it/bitstream/11577/3257934/1/Tarolli%20et%20al.%20%282017%29.pdf

Mapping the topographic fingerprints of humanity across Earth

Abstract

Similar works

Full text

Available Versions

Crossref

Archivio istituzionale della ricerca - Università di Padova

Padua Research Archive