On May 21^st, our sixth Quadtrees Hub will take place. The aim is to share and discuss research in progress. Quadtrees’hubs are open to anyone interested and somehow familiar with some quantitative techniques and willing to progress with these. Please contact Isabelle Pigeron-Piroth for information.

When? 21^st May 2021, 2 to 3 pm

Where? via Webex

2-3 pm : Marlène Boura  (University of Luxembourg, DGEO): Towards a spatially explicit urban CO₂ budget. Urban carbon emissions, dispersion and sequestration in Europe

Modelling a steady-state urban carbon balance for 802 European cities at a fine spatial resolution.

Anthropogenic CO2 emissions are downscaled spatially (down to 1 ha) and temporally (from annual to daily) based on the sector of activity, the land use category and the location. Sequestration of CO2 is estimated for different types of urban vegetation, following the IPCC guidelines at the same spatial and temporal resolutions.

For one typical day of each month, we simulate 2 steady-state situations for the CO2 molecules dispersion and capture. The absolute carbon balance and the relative carbon capture (as a percentage of effective anthropogenic emissions) are then computed. The data produced can be used to assess the spatial heterogeneity of the carbon balance within a specific urban area. It can also be used to assess how much of its own emissions an urban area can capture.

Zenodo: http://doi.org/10.5281/zenodo.4301952

Description

The datasets provide a typology for 689 European urban areas, the land cover metrics and landscape metrics used to create the typology and the Urban Forest Ecosystem Services (UFES) indexes created from them.

The typology of Urban Forest Ecosystem Services (UFES) presents 10 clusters of cities aggregated into 4 groups: Forest cities (F1-4), Anthropogenic cities (A1-3), Herbaceous cities (H1-2) and Standard European cities (E1). The data can be used to support urban planning policies at local and regional scales; in urban forestry, urban form and ecosystem services work-related at different spatial scales. The metrics used capture the spatial integration of different layers of natural, semi-natural and artificial land within functional urban areas.

The data refers to the article under revision “Urban Forests Ecosystems in Europe: Types and Ranking of Cities”

In the context of population growth and urbanisation, associated with an increase of GHG concentration in the atmosphere, the impact of human activities on climate change is ever increasing. Simultaneously, the pressure on natural ecosystems especially within and around cities becomes harder. We contend that these natural ecosystems are important to mitigate climate change, if we would be able to understand better how the services they provide to Earth and mankind vary across and within cities, especially along different spatial arrangements of anthropogenic and natural lands.

The majority of GHG emissions arise from anthropogenic activities within urban areas, while the most important potential carbon sinks lie within natural and semi-natural areas. The further agglomeration of the population in cities but also the last two decades of density planning are both aggregated views of cities which ignore the spatial pattern of carbon sources and sinks. A deeper understanding is needed on how urban areas can cope with their own emissions, and at which magnitude, compared to global scale effects. The objective of this project is to provide insights on how urban forms and their inner characteristics relate to carbon dioxide (CO2) profiles. More particularly, it analyses the level of integration of urban forest (i.e., all elements of urban vegetation) present within the built-up footprint and within functional urban areas in order to derive the effect of their spatial distribution on CO2 flows and aggregated budgets.

The research is conducted at a geographically detailed scale for hundreds of Functional Urban Areas (FUAs) in Europe. It is structured in three stages as follows:

• Urban Forest Ecosystem Services (UFES) typology: How much variation exist in Europe in the spatial integration and characteristics of urban forests within urban settlements. Are there clear types and how can they potentially support ES arising from the urban forest? Are there mismatches between needs and provisions of urban forests ES in general or for some urban types?

• CO2 flows and UFES typology: How does the relative spatial pattern of urban forests (and their characteristics) within urban areas impact the CO2 uptake potential? Modelling of spatial explicit CO2 flows for European urban areas and analysis of the link between the typology and the carbon profile.

• Spatial boundaries and CO2 profiles: How does the definition of urban boundaries affect CO2 budget appraisal? (functional-radial-morphological approaches). What is the impact of choosing a city, metropolitan, regional, national, continental scale for appraisal? How can each of these scales be relevant against planning capacities and land use policies?

This PhD project is held at the University of Luxembourg and the Thesis Supervisory Committee (CET) is constituted of:

-Prof. Geoffrey Caruso: University of Luxembourg (Department of Geography and Spatial Planning), Luxembourg Institute of Socio-Economic Research (LISER) – Supervisor

-Prof. Cecil Konijnendijk van den Bosch: University of British Columbia (Department of Forest Resources Management)

-Prof. Mohamed Hilal: AgroSup Dijon and INRA (UMR CESAER)