"Humans Dominated Earth Earlier Than Previously Thought"

 

Scientists from various disciplines worldwide nowadays poole their knowledge of past land use — and pushed back the date when human farming and other practices began altering the planet. This is important since land use (change) has been (and still is) a significant factor to (past) climate change – and a possible tool to mitigate future climate change as well.

Currently, a heavily debated hypothesis about past changes in human history is the one formulated by Bill Ruddiman, a marine biologist. “His hypothesis is arguing that the significant footprint of human add-on to climate began thousands of years ago and not just 150 years or so, which is the conventional view.” Think of permanent agriculture, livestock herding, mining and largescale conversion (deforestation) of natural ecosystems. So, it really changes how we perceive the timing of human impact on the global climate system.

Therefore, my work focuses on historical land-use reconstructions (the HYDE database) covering the whole Holocene which can be freely used by modelers and teachers, to better understand the underlying processes and consequences of land changes, so that we can make better policy decisions for a sustainable future.

 

Kees has 30 years of experience in environmental research, with particular emphasis on integrated global environment assessments. He is interested in (historical) land-use modeling/reconstructions, and working across disciplines such as History, Archaeology, Paleoecology, and also in the feedback mechanisms of these historical land-use changes to the global carbon cycle and climate. He is the founder and developer of the History Database of the Global Environment (HYDE) and has many publications in the field of global environmental problems.

 

Grants.

  • UU Early Career Fund (ca. 260k Euro), period 2023 - 2027.
  • UU FAIR IT fund (50k Euro), period 2023 - 2024.
  • International Future Anthromes workshop organization (10k euro), April 2022.
  • NWO - VENI grant (250k euro), period 2014 - 2018.
     

Awards. Most highly cited papers rank worldwide in the top 1% by citations for a field or fields (source: Clarivate Analystics)

  • Highly Cited Researcher in the field of Cross-Field - 2022
  • Highly Cited Researcher in the field of Cross-Field - 2021
  • Highly Cited Researcher in the field of Cross-Field - 2020
  • Highly Cited Researcher in the field of Cross-Field - 2019
  • Highly Cited Researcher in the field of Cross-Field - 2018

 

Current projects.

 

PhD on the Footprint of Colonialism: Attributing Biodiversity Loss and GHG Emissions from Colonial Land Change Processes (supervisor, Co-promotor)

Quantifying the cumulative attribution of countries to biodiversity loss and greenhouse gas (GHG) emissions arising from land change is of critical importance to achieve global environmental justice. Attribution of individual countries to past land change in an objective manner gives clear information for negotiations around loss and damage finances as recently debated at United Nations conference on climate Change (COP27) and biodiversity (COP15). 

 

The aim of this project is to quantify the relative attribution of different countries to biodiversity loss and GHG emissions arising from land change since the colonial period using footprint analysis. This will illustrate to what extent the burden of resource extraction has shifted over time and how colonial legacies impact environmental footprints in present day. We will use an approach that integrates the HYDE database of landcover change with reconstructions of resource flows based on historical data and footprint modelling techniques

 

HYDE project (principal investigator)

The current HYDE version is an updated and internally consistent combination of historical population estimates and also an implementation of improved allocation algorithms with time-dependent weighting maps for cropland and grassland, while the period covered is 10,000 BCE to 2023 CE. Continuous updating and elaboration of historical and archaeological sources is in full progress. Version 3.3 has now included a distinction of grazing land into pasture, natural rangeland and converted rangeland, as well irrigated areas and rice. Also, version 3.3 includes radiocarbon data on the onset of agriculture for Eurasia, yearly satellite information from 1992-present, a first draft for shifting culitvation.

 

LANDCOVER6K working group project (contributor)

PAGES (Past Global Changes) supports research aimed at understanding the Earth’s past environment in order to make predictions for the future. Adequate incorporation of land cover in global and regional climate models is still one of the major priorities in the climate modelling community. In particular, anthropogenic land cover change (ALCC) is still not successfully implemented in these models. As a result, climate modelling in paleo-mode or projection mode that tries to take ALCC into account is seriously hampered (Strandberg et al., 2014).

 

This is due to the fact that:

i) the dynamic vegetation models coupled to global climate models (GCMs) or regional climate models (RCMs) simulate climate-induced vegetation (i.e. potential, natural vegetation) but cannot yet simulate anthropogenic vegetation, and

ii) the scenarios of past ALCC, e.g. HYDE (Klein Goldewijk et al., 2011; 2013), KK10 (Kaplan et al., 2010) and others, show very large differences (Gaillard et al., 2010).

 

The question of whether humans had more impact on climate in prehistory (from 3k BP or earlier) than previously assumed, is still a matter of debate. Thus, the effect of anthropogenic burning and deforestation on global climate via biogeochemical and biogeophysical processes in the past is not fully understood yet, and mitigation strategies using e.g. tree plantations to create CO2 sinks and climate cooling might be erroneous. Improved descriptions of past anthropogenic land cover change at the global spatial scale are therefore needed.

LandCover6k will build on, and expand, the pollen-based reconstruction work of PAGES' Focus 4 theme, Land Use and Cover. It will bring together paleoecologists, historians, archeologists, and modelers to explore and provide new information about ALCC. It aims to create products suitable for climate modellers and climate change policy makers.

 

Global Carbon Project (contributor)

The Global Carbon Project (GCP) was established in 2001 in recognition of the large scientific challenges and critical nature of the carbon cycle for Earth's sustainability. The scientific goal of the project is to develop a complete picture of the global carbon cycle, including both its biophysical and human dimensions together with the interactions and feedbacks between them. HYDE provides yearly updates on the land use part.

 

LUMIP | Land Use Model Intercomparison Project (contributor)

Human land-use activities have resulted in large changes to the biogeochemical and biophysical properties of the Earth surface, with resulting implications for climate. In the future, land-use activities are likely to expand and/or intensify further to meet growing demands for food, fiber, and energy. CMIP5 achieved a qualitative scientific advance in studying the effects of land-use on climate, for the first time explicitly accounting for the effects of global gridded land-use changes (past-future) in coupled carbon-climate model projections. Enabling this advance, the first consistent gridded land-use dataset (past-future) was developed, linking historical land-use data, to future projections from Integrated Assessment Models, in a standard format required by climate models. Results indicate that the effects of land-use on climate, while uncertain, are sufficiently large and complex to warrant an expanded activity focused on land-use for CMIP6.

 

(Future) ANTHROMES project (principal investigator and contributor)

The Anthromes Project aims to investigate, understand and model human transformation and management of the terrestrial biosphere based on the concept of Anthromes (Anthropogenic Biomes) as a new paradigm for incorporating human systems into global ecology and earth science research and education for the Anthropocene. Currently, we are working on the Anthropogenic Transformation of the Holocene and of the Future with prof. dr. Erle Ellis, Univ. of Baltimore, USA. (see http://ecotope.org/anthromes/)

 

Older projects.

IMAGE 3.0

IMAGE is an ecological-environmental framework that simulates the environmental consequences of human activities worldwide. It represents interactions between society, the biosphere and the climate system to assess sustainability issues like climate change, biodiversity and human well-being. The objective of the version of IMAGE 3.0 (update of version 2.4 released in 2006) is to explore the long-term dynamics of global change as the result of interacting demographic, technological, economic, social, cultural and political factors. New features of IMAGE 3.0 will be (amongst other parts) land use modeling on a 5 arcminute resolution, a new LPJml dynamic vegetation module, and a new Forest Management Module (www.pbl.nl/image)

 

BEO

Biodiversity, Ecosystem goods and services and Developments issues (BEO). It's about quantifying ecosystem degradation and its role on human affairs: mapping & quantifying lost functions on a global scale, for current and pristine conditions.

 

CLIO-INFRA

In 2010, NWO awarded a subsidy to the Clio Infra project, lead by Prof. dr. Jan Luiten van Zanden of the International Institute of Social History (IISH). Under the title of Clio Infra, a set of interconnected databases has been set up containing worldwide data on social, economic, and institutional indicators for the past five centuries, with special attention to the past 200 years. These indicators allow research into long-term development of worldwide economic growth and inequality.

 

Global inequality is one of the key problems of the contemporary world. Some countries have (recently) become wealthy, other countries have remained poor. New theoretical developments in economic science - such as new institutional economics, new economic geography, and new growth theory - and the rise of global economic and social history require such processes to be studied on a worldwide scale. The question of worldwide economic growth and inequality can only be researched on the basis of worldwide data concerning the patterns of economic performance and their causes. Clio Infra provides datasets for the most important indicators. Economic and social historians from around the world have been working together in thematic collaboratories, in order to collect and share their knowledge concerning the relevant indicators of economic performance and its causes. The collected data have been standardized, harmonized, and stored for future use. New indicators to study inequality have been developed. The datasets are accessible through the Clio Infra portal which also offers possibilities for visualization of the data (http://www.clio-infra.eu/)

 

The unique global datasets enable new opportunities for data analysis and the testing of hypotheses from new economic theories. Clio Infra offers the opportunity to greatly enhance our understanding of the origins, causes and character of the process of global inequality. 


LandCover6K