GC11A-0662
Holocene = Anthropocene? The HYDE database for integrated global change research over the past 12,000 years
More and more studies of global (climate) change are focusing on the past. Hundreds and thousands of
years of land use, driven by population growth have left their trace/mark on the Earth's surface. We are only
at the beginning to understand the complex relationship of human induced disturbances of the global
environment, and the consequences for future climate. It is therefore essential that we get a clear
picture/understanding of past relationships between population growth, land use and climate. In order to
facilitate climate modelers to examine these relationships, the HYDE database has been updated and
extended.
The update of HYDE described here (Klein Goldewijk et al. 2006; Klein Goldewijk et al. 2007) includes
several improvements compared to its predecessor: (i) the HYDE 2 version used a Boolean approach with a
30 minute degree resolution, while HYDE 3 uses fractional land use on a 5 minute resolution; (ii) more and
better sub-national (population) data (Klein Goldewijk, 2005) to improve the historical (urban and rural)
population maps as a basis for allocation of land cover; (iii) implementation of different allocation algorithms
with time-dependent weighting maps for cropland and grassland; (iv) the period covered has now been
extended from the emergence of agriculture (10,000 B.C) to present time (2,000 A.D.), with different time
intervals.
Examples of (future) use of the database is to help test the 'Ruddiman hypothesis', who proposed a theory
that mankind already altered the global atmosphere much earlier than the start of the Industrial Revolution in
the early 18th century (Ruddiman, 2003), which put forward the research question whether we detect a pre-
Industrial Revolution anthropogenic signal, and how strong is that signal?
References
Klein Goldewijk, K. A.F. Bouwman and G. van Drecht, 2007. Mapping current global cropland and grassland
distributions on a 5 by 5 minute resolution, Journal of Land Use Science, Vol 2(3): 167-190.
Klein Goldewijk, K. and G. van Drecht, 2006. HYDE 3: Current and historical population and land cover. MNP
(2006) (Edited by A.F. Bouwman, T. Kram and K. Klein Goldewijk), Integrated modelling of global
environmental change. An overview of IMAGE 2.4. Netherlands Environmental Assessment Agency (MNP),
Bilthoven, The Netherlands
Klein Goldewijk, K. 2005. Three centuries of global population growth: A spatial referenced population
density database for 1700 – 2000, Population and Environment, 26 (5): 343-367.
Ruddiman, WF, 2003. The anthropogenic greenhouse era bagan thousands of years ago, Climatic Change,
61(3), 261-293.
http://www.mnp.nl/hyde
GC11A-0663
No Free Lunch – Trading Away Ecosystem Services from Agriculture in the Brazilian Amazon
In the age of globalization, many crops and animal products are transported across the long distances for consumption elsewhere. The alteration of water, soil and climate systems from agricultural practices can be attributed to both exporting and importing countries. Quantities of water, carbon and nutrients (e.g. nitrogen and phosphorus) can be tracked throughout the production process and be aggregated from field to table. The synthesis of this data can be used to inform markets to appropriately price the most ecologically efficient production.While agricultural land is undergoing changes around the world, the Brazilian Amazon has seen a dramatic conversion of forest and grassland due to the expanding agricultural frontier, and intense growth in the future has been predicted in the region. As a proof of concept, I plan to study the flow of ecosystem services from the Amazon rainforest basin to the world market. Cattle and soybeans are the two main agricultural products of the region and are produced for both internal consumption and for export. This work quantifies agricultural production and its associated ecosystem services using socio-economic and commodity trade data, numerical ecosystem models and remote sensing products.
GC11A-0664
Stratigraphy of the Anthropocene
The Anthropocene is an informal unit that has recently been introduced to refer to the current interval of anthropogenic global environmental change. It is being increasingly adopted in the scientific literature, and has also attracted widespread public interest in emphasizing the scale of contemporary environmental perturbation. An argument may therefore be put forward for its eventual formalization. Such formalization would be the responsibility of the International Commission on Stratigraphy (ICS) and would be preceded by formation of an Anthropocene Working Group, best attached to the Subcommission on Quaternary Stratigraphy. Consideration of evidence for and against formalization would take several years, and would enter novel territory for such discussions. This might include assessment of ongoing environmental change in the context of the near-present and earlier stratigraphic record, and likely also forward-modelling (of sea level, ocean/atmospheric chemistry, biotic composition and so on). Consideration of an effective boundary needs also be made, including whether it should be linked to a Global Stratigraphic Section and Point (GSSP) or Global Stratigraphic Standard Age (GSSA), and also of the hierarchical scale of the unit. We here ask the ICS to establish an Anthropocene Working Group, without prejudice to the eventual outcome. As in past determinations of formal chronostratigraphic boundaries, focussing scientific debate on this question would provide valuable data and insights to both the geological and wider scientific communities
GC11A-0665
Anthropogenic Transformation of the Biomes, 1700 to 2000
Current global patterns of terrestrial ecosystem form and process are now predominantly anthropogenic as a
result of land use and other direct human interactions with ecosystems. This study investigates
anthropogenic transformation of the terrestrial biosphere over the course of the industrial revolution by
mapping and characterizing global transitions between wild and anthropogenic biomes between 1700 and
2000. A global map of potential natural vegetation was used to represent wild biomes. Anthropogenic
biomes were mapped for 1700, 1800, 1900 and 2000 using rule-based classification of current and historical
global data for human population density, urban area and percent land cover by cultivated crops (rainfed,
irrigated, and rice) and pastures. By assuming that wild, climate-driven, biome patterns have been relatively
constant since 1700, transitions between wild and anthropogenic biomes were characterized between 1700
and 2000 at century intervals. Historical analysis of wild to anthropogenic biome transitions reveal the global
transition from a primarily wild to a primarily anthropogenic terrestrial biosphere. Moreover, by mapping and
examining global transitions between wild and anthropogenic biome classes, we provide a simple framework
for assessing and modeling both past and future global biotic and ecological patterns in the light of the
extent, intensity and duration of their modification by humans.
http://ecotope.org/projects/anthromes
GC11A-0666
Warming of the Continents in the Anthropocene
The Intergovernmental Panel on Climate Change (IPCC) reports a very high confidence that anthropogenic activities have warmed the climate system. A significant component of this warming climate system is the continental lithosphere where measurements of temperature-depth profiles from boreholes contain valuable information about the changing surface temperature and provide a direct method for reconstructing surface temperature variations over the past several centuries. The borehole record indicates that ground temperatures began notably heating in the mid-1830's with a total increase approaching 1 °C at the ground surface, comparable to the atmospheric temperature rise over the same time. This temperature change resulted in an increase in the heat content of the outermost part of the continental lithosphere on order of 1.55 x 1022 J, equivalent to an additional heat flux of 15 mW m-2 over the last 170 years. By utilizing the physics of heat diffusion and the theory of borehole thermometry, we have modeled the future temperature state of the continental lithosphere using three emission scenarios (A2, A1B, and B1) from the IPCC AR4, along with a minimum commitment scenario. Our results indicate the heat content increase for the next century will be between 3.11 (for the minimum commitment scenario) and 9.42 x 1022 J (for scenario A2) with the three-scenario mean at nearly 8 x 1022 J. These heat content increases are equal to an additional heat flux of almost 60 mW m-2 at the ground surface over the next 100 years. While this change in heat content is less than estimates for the ocean, it nevertheless is an important component of the climate system, and can be directly linked to the anthropogenic influence on climate change.
GC11A-0667
Is Net Primary Production a function of human population density?
Terrestrial Net Primary Production (NPP) is typically modeled as a function of biophysical variables and land- use. However, in a recent publication on Anthropogenic Biomes, Ellis and Ramankutty postulated that ecosystem functioning today is under direct control of humans. Indeed, here we show that global patterns of NPP also vary as a function of human population density. In highly productive biomes, NPP declines with both increased population density and cultivated land area, while in less productive biomes the opposite is observed. Thus, humans appear to exert a global leveling effect on terrestrial NPP. Moreover, the relationship between NPP and population density holds across cultivation levels, implying that human influence on NPP is not simply the result of changes in land cover. We believe that previous studies have missed this relationship by failing to stratify analyses of human/NPP relationships within specific biomes. Although causality cannot be established by our empirical analysis alone, the population/NPP relationship merits greater study and inclusion in terrestrial ecosystem modeling.
GC11A-0668
Determination of Platinum and Iridium in Rainwaters by HR-ICP-MS
The concentrations of platinum group elements (PGEs) are rapidly increasing in many environmental matrices with the advent of automobile catalytic converters and the utilization of catalysts in diverse industrial processes. Atmospheric precipitation is an important process constituting the global geochemical cycle and can directly impact the ecosystem. However, the relatively low concentrations in rainwater have hindered their measurement, and the impact to the environment of present and future increases in PGEs is difficult to evaluate. In this study, we have used the high resolution inductively coupled plasma mass spectrometer coupled with a desolvation system to measure PGE concentrations in rainwaters collected in Seoul, Korea. The samples were collected at the Gwanak Mountain during summer including the monsoon period. The detection limits for iridium (Ir) and platinum (Pt) were 2.5 and 3.0 pg L-1 ( pg = 10-12 g), respectively, and average concentrations in rainwater were Ir: 23.2 pg L-1 and Pt: 34.4 pg L-1. The observed values of Ir and Pt in rainwater in the Seoul region were approximately 45 and 100 times higher than ancient ice core samples from 130-150 ka, the background level from natural sources. On the other hand, when compared to recent studies of rainwater in other regions, the concentration of Pt in Seoul rainwater was relatively low which may be due to the geographical differences in PGE emission sources. Additionally, in our study, concentrations of Ir and Pt in rainwater are well correlated with each other and have inverse correlation to the rainfall amount. It may be concluded that the concentration of PGEs in rainwater is diluted by extreme rainfall during summer time.
GC11A-0669
Changes in Soil Organic Matter Related to Suburban Growth Into Agricultural and Forested Areas
Suburban growth has primarily been associated with an increase in impervious surface over once vegetated landscapes. An image of rows of identical homes rolling over the hills of an old farm, with paved parking lots, shops and town centers, is common to many Americans today. As a result, the extent of managed vegetated landscapes common to suburban development, such as turf lawns, are increasing as well. Yet suburban landscapes are generally a mix of different cover types including managed forests, gardens and grasses and it is common today for developments to be designed with plenty of different types of green space for new residents to enjoy. This paper explores how land use changes from dominantly forested and agricultural to suburban development may affect soil organic matter. Has the replacement of forests and agricultural land by suburban development resulted in a loss in soil organic matter of the local soils? We look at the suburbs of Baltimore MD as a case study - an area studied extensively by the Baltimore Ecosystem Study as an NSF Long-Term Ecological Research Site and the site of the first carbon flux tower in an urban environment. We combine soils data with high-resolution mapping to conduct a multi-temporal analysis of suburban landscape change and its influence on soil biogeochemistry from the 1950s to 2003.
GC11A-0670 INVITED
Friend or Foe? Urbanization and the Biosphere
The environmental influence of urban areas is still often assumed to be negligible at global scales. Although local environmental conditions such as the urban heat island effect are well-documented, surprisingly little work has focused on cross-scale interactions, or the ways in which local urban processes cumulatively impact global changes. Given the rapid rates of rural-urban migration, economic development and urban spatial expansion, improved systems for measuring, monitoring and modeling the global environmental impacts of cities should receive far greater scientific attention. This presentation will summarize urban environmental issues and impacts at local, regional and global scales and introduce the fundamental concepts and tools needed to measure and respond to these problems. Newly available datasets for the distribution and intensity of urban land use will be introduced, demonstrating the importance of clearly defining 'urbanized' land for empirical studies at the global scale. The negative environmental impacts of urban development will be compared with the often over-looked "positives" of urban growth from a global environmental perspective. Progress in understanding and forecasting the global impacts of urban areas will require systematic global urban research designs that treat cities as urban systems, anthropogenic biomes and urban ecoregions. The challenges and opportunities of global environmental research on urban areas have important implications not only for current research but also for educating the next generation of earth system scientists.
GC11A-0671
Development of a Spacious (Pre- and Proto) Historic Inland Dune Landscape in Lower Bavaria, Germany
The dune fields in Bavaria are generally supposed to have been developed during the last glacial maximum (LGM). New results show, that developing a real dune landscape Holocene and anthropogenic influences have been more important. In 2005 detailed geomorphologic research on the dune bodies were started. The basics of the stratigraphic composition of the dunes, the transition from dune bodies into thinner areas of sanddrift, a description of the dune basins, the shape of the dunes and their alignment could be compiled. Furthermore several dunes and sanddrift fields could be dated by means of OSL on sediments and radiocarbon dating on charcoals found in fossil soils. The results show, that the anthropogenic influence as enduring settlement, agriculture and forestry are of major importance for the development of the dune fields and their Holocene phases of mobilization. The sanddrift fields and inland dunes near Abensberg and Siegenburg (Lower Bavaria) developed in an area of transition from later Tertiary delta deposits of the ancient Naab river system and Pleistocene, complex structured gravels of the Danube River and the Abens River, which have changed their stream courses several times during the Quaternary. Besides alluvial gravels, the sanddrift and dune fields consist of Tertiary sands of feldspar with high concentrations of mica from the Tertiary Hills of Lower Bavaria. Beginning with the bronze age the dunes got mobilized again during phases of extensive clearing. There is evidence for these processes in form of several buried soils in the dune bodies. The most common dune forms in the region are longitudinal dunes with a great variety in altitude (up to 15 m of maximum height). High resolution landscape models have been created, based on field work and laserscanning data. Resulting from geophysical prospections, selected dunes and the surrounding areas of sanddrift are structured according to different times and types of mobilization and sedimentologically characterized.
GC11A-0672
Improved Data, Models and Investigations of Anthropogenic Effects on Freshwater Ecosystems at a Global Scale
Anthropogenic effects on the biosphere are typically assessed with a terrestrial focus. In most approaches, the impact of humans is estimated or modeled based on population density maps, by applying buffer zones around population centers or by defining the range of influence around terrestrial infrastructure. If atmospheric processes are taken into account (such as air pollution or climate change) the effects are mostly assigned to terrestrial units like countries or terrestrial ecosystems. Only few studies investigate the anthropogenic effects on freshwater ecosystems, not least due to a severe lack of appropriate data sources and models. As a key distinction to the terrestrial approaches, freshwater studies need to take river topology and connectivity into account. Models need to incorporate the process of anthropogenic effects being propagated and accumulated along river networks, and appropriate modeling frameworks and data sources need to be prepared. Recently, several new datasets have become available to allow for a new generation of such studies. This presentation will focus on selected new data developments and discuss their possible application towards assessing the human influence on global river systems, lakes and wetlands. Key data layers include the global distribution of human-made reservoirs (GRanD Database), the anthropogenic withdrawals of water resources (based on global model results), and a high resolution global river network (HydroSHEDS).
GC11A-0673
Recent Changes of Permafrost and Cold Regions Environments in the Northern Part of Northeastern China
The Northeastern China is located on the eastern margin of the Eurasian Continent in the mid- to high- latitudes. It is one of the subarctic permafrost in mountainous areas that has been most remarkably affected by the dramatic climate warming and ever increasing human activities. The presence of permafrost is closely related to the cold climates, topography and geomorphology, surface coverage of forests and wetlands vegetation, and snow cover. During the last four decades, permafrost has been in rapid degradation as evidenced by the deepening active layer, thinning permafrost, rising ground temperatures, expanding taliks, and disappearing patches of permafrost. The major causes of permafrost degradation include the pronounced climate warming, and human activities including rapid urbanization, overgrazing and inappropriate farming of grasslands and forested land, and building and operation of substantial (express) highway and railway networks. Under the projected climate warming scenarios and the subsequent synchronous degradation of permafrost, there has been and would be a series of ecological and environmental changes such as the shrinkage of wetlands, the desertification of steppes and the deforestation. All of these would further cause the degradation of permafrost, which might form a vicious feedback cycle in the evolution of ecosystems if no adequate mitigative measures are taken.
GC11A-0674
From the ground up: The role of climate versus management on global crop yield patterns
Agricultural lands are one of the most expansive land cover types on Earth, extending across approximately 12 percent of the planet's land surface. The management of these lands has changed dramatically since the Green Revolution of the 1960s. Nitrogen fertilizer inputs are almost 7 times greater, and irrigated lands have nearly doubled. Yet, the number of undernourished people is still increasing, and may continue to as the world's population is expected to grow by 2.5 billion people over the next three decades. In addition, there is a shift toward diets heavy in grain-fed meats taking place, as well as an increase in the demand of grains for fuel. While an altered distribution of crops may help remedy some of our food shortages, humanity will need to produce more if it is to meet its demands for crops. Obtaining more crops could entail both an expansion of agricultural lands as well as a change in the way many lands are currently managed - scenarios that would have implications for ecosystem goods and services at large given agriculture's already prominent place on the planet's landscape. Here, we explore society's ability to increase yields on existing croplands by way of altered management. We begin by quantifying the current influence that management practices such as chemical fertilizer use and irrigation have on global crop yield patterns relative to biophysical factors such as climate. In particular, we test the traditional assumption that more intensively managed lands have higher yields. We utilize new global, gridded maps of cropland cover and yields, as well as new maps showing climatically determined crop yield potentials. With this, we hope to contribute to a discussion of how we might, as a civilization, continue to shape our planet's land cover in pursuit of food, feed, and fuel.
GC11A-0675
Organic Chemostratigraphic Markers Characteristic of the (Informally Designated) Anthropocene Epoch
Recognizing the tremendous collective impact of humans on the environment in the industrial age, the proposed designation of the current time period as the Anthropocene Epoch has considerable merit. One of the signature activities during this time continues to be the intensive extraction, processing, and combustion of fossil fuels. While fossil fuels themselves are naturally-occurring, they are most often millions of years old and associated with deeply buried strata. They may be found at the surface, for example, as natural oil seeps or coal seam outcrops, but these are relatively rare occurrences. Fossil fuels and their myriad by- products become the source of distinctive organic chemostratigraphic marker compounds for the Anthropocene when they occur out of their original geological context, i.e., as widespread contaminants in sediments and soils. These persistent compounds have high long-term preservation potential, particularly when deposited under low oxygen conditions. Fossil fuels can occur as environmental contaminants in raw form (e.g., crude petroleum spilled during transport) or as manufactured products (e.g., diesel oil from a leaking storage facility, coal tar from a manufactured gas plant, plastic waste in a landfill, pesticides from petroleum feedstock in agricultural soils). Distinctive assemblages of hydrocarbon marker compounds including acyclic isoprenoids, hopanes, and steranes can be readily detected by gas chromatography/mass spectrometric analysis of surface sediments and soils. Polycyclic aromatic hydrocarbons (PAHs), along with sulfur-, oxygen-, and nitrogen-containing aromatic compounds, are also characteristic of fossil fuels and are readily detectable as well. More widespread is the airfall deposition of fossil fuel combustion products from vehicular, domestic and industrial sources. These occur in higher concentrations in large urban centers, but are also detected in remote areas. Parent (nonmethylated) PAHs such as phenanthrene, fluoranthene and pyrene are the most abundant organic marker compounds in these combustion-derived deposits, distinguishable in their types and proportions from the combustion products of natural vegetation fires. The occurrence of specific fossil fuel combustion-derived PAH assemblages serves as a stratigraphic signature for Anthropocene deposits.