G
The Scientific Engine of the Gigaton Project

The 'G' Lab

G — for Gigaton. The unit that defines the scale.

Every recommendation the Gigaton Project makes traces back to research produced here. The 'G' Lab is where 25 years of urban climate science by Prof. Dr. Jürgen Kropp's group at PIK becomes actionable tools, open datasets, and peer-reviewed findings — ready for cities, corporations, and policymakers to act on.

119
Peer-reviewed publications
25+
Years of urban climate research
4
Research frontiers · Nature Sustainability
Scientific Founder

The researcher behind the Lab

Prof. Dr. Jürgen P. Kropp
Founder · The 'G' Lab
Prof. Dr. · PIK Potsdam · University of Potsdam

Jürgen P. Kropp

Deputy Head, Climate Resilience Department · PIK
Head, Urban Transformation Research Group · PIK
Extraordinary Professor, Climate Change & Sustainable Development · University of Potsdam

A chemist and physicist by training, Jürgen Kropp has spent more than two decades at the Potsdam Institute for Climate Impact Research developing the scientific tools to understand cities as carbon-emitting, heat-producing, and food-consuming systems. His group's research — spanning urban emission profiles, built environment carbon costs, heat burden modelling, and the nexus between corporate and urban climate action — forms the direct scientific foundation of the 'G' Lab and every recommendation that flows from it.

119
ISI journal articles,
books & chapters
25+
Years leading urban
climate research at PIK
RD2
PIK Climate Resilience
Department
PIK Profile → Publications → Google Scholar →
The Science

Four Research Frontiers

These four frontiers define the scientific backbone of the Gigaton Project. Every tool, dataset, and recommendation we produce is grounded in at least one of them.

Accepted Gudipudi R, Costa L, Arumugam P, Agarwala M, Kropp JP, Creutzig F — "From Corporate Net-Zero Pledges to Credible Climate Action." Nature Sustainability, 2025.
1
Research Frontier 1

Harmonised Emission Accounting

Corporate and city emission inventories are currently incompatible — different scopes, boundaries, and methodologies make comparison meaningless. RF1 develops the harmonised accounting frameworks that allow emissions to be counted consistently across sectors, geographies, and reporting standards.

Consistent, comparable data across actors
2
Research Frontier 2

Industry-Specific Decarbonisation Pathways

A single decarbonisation trajectory cannot serve steel, cement, aviation, and agriculture equally. RF2 builds sector-by-sector science-based pathways that reflect the different physics, economics, and timescales of each industry — enabling realistic, credible targets rather than uniform pledges.

Sector-specific roadmaps, not one-size-fits-all
3
Research Frontier 3

Mathematical Decomposition of Year-to-Year Emissions

When a company reports a 6% emission reduction, what caused it — a drop in production activity, a genuine efficiency gain, or a fuel-mix shift? RF3 applies formal decomposition methods to disentangle these drivers, making emission trends interpretable, attributable, and auditable.

What's actually driving change — visible
4
Research Frontier 4

Industry-Specific Residual Emissions

Even after maximum decarbonisation effort, some emissions cannot be eliminated with current technology. RF4 quantifies this hard-to-abate floor for each sector — establishing what residual emissions are scientifically defensible, and what claims of net-zero actually require.

The honest floor — after maximum action
👥
Group photo
coming soon
Prof. Kropp's research group · Urban Transformation
The Research Legacy

From PIK to the
'G' Lab — a body of work in motion

After more than two decades leading the Urban Transformation Research Group at the Potsdam Institute for Climate Impact Research, Prof. Kropp has brought his entire scientific programme to the Gigaton Project. The 119 publications, the methodologies, the models — this accumulated body of work now forms the independent scientific foundation of the 'G' Lab, carried forward under new institutional homes and with full independence.

🌍
Bauhaus der Erde: Prof. Kropp is a shareholder at Bauhaus der Erde, co-founded alongside Prof. Dr. Hans Joachim Schellnhuber and Marc Weissgerber — a platform at the intersection of sustainability science, design, and societal transformation.
🔬
IIASA: Prof. Kropp holds an active position as Senior Researcher at the International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria — continuing his work on complex human–environment systems.
📄
Research heritage: 119 peer-reviewed publications built at PIK across Nature journals, Environmental Research Letters, Nature Communications, and more — now the independent scientific backbone of the 'G' Lab.
⚗
The 'G' Lab: An independent, institutionally unaffiliated research and tool production unit — drawing on Prof. Kropp's body of work to generate recommendations, data, and models for the Gigaton Project.
Bauhaus der Erde ↗    IIASA ↗
From the Research

Landmark Findings

What 25 years of research established — and what each finding means for how we design the Gigaton Project's recommendations.

RF1 · RF2
1.5°C
Constructing the global built environment alone can preclude the 1.5°C climate target — before a single building is operated.
Li C, Pradhan P, Chen G, Kropp JP, Schellnhuber HJ · Nature Communications: Earth & Environment · 2025
RF1 · RF3
5
Four research frontiers form the science-based bridge from corporate net-zero pledges to credible, verifiable climate action.
Gudipudi R, Costa L, Arumugam P, Agarwala M, Kropp JP, Creutzig F · "From Corporate Net-Zero Pledges to Credible Climate Action" · Nature Sustainability · 2025 (accepted)
RF1 · RF4
3×
Climate extremes in Europe are increasingly co-occurring, compounding, and persistent — their frequency has roughly tripled compared to mid-20th-century baselines.
Pradhan P, Seydewitz T, Zhou B, Luedeke MKB, Kropp JP · Anthropocene Science · 2022
RF2
71%
Agricultural emission accounting shifts substantially when adjusted for trade — meaning where emissions are reported matters as much as how much is emitted.
Foong A, Pradhan P, Fröer O, Kropp JP · Nature Communications · Vol. 13, 2022
What the Lab Produces

Tools & Open Data

The 'G' Lab translates research into usable instruments — datasets, models, and analytical tools that cities and corporations can apply directly.

📊
Municipal Emissions Disaggregator
Spatially resolved emission data for municipalities across end-use sectors, enabling city-level carbon accounting at the resolution corporate Scope 3 frameworks require.
Based on: Patil S, Pflugradt N, Weinand JM, Kropp JP, Stolten D · Scientific Data · 2025
In development
🏗️
Built Environment Carbon Model
Quantifies embodied carbon in the construction of buildings and infrastructure — connecting the urban development pipeline to national and corporate decarbonisation targets.
Based on: Li C, Pradhan P, Chen G, Kropp JP, Schellnhuber HJ · Nature Comm. E&E · 2025
In development
🔍
Emission Decomposition Toolkit
Applies RF3 decomposition methods to reported corporate emission series — attributing year-on-year changes to activity, efficiency, and fuel-mix effects with mathematical rigour.
Grounded in: Research Frontier 3 · Gudipudi et al. · Nature Sustainability · 2025
In development
🎯
Residual Emissions Benchmarker
Establishes sector-specific residual emission floors — helping corporations distinguish scientifically defensible net-zero claims from those that require offsetting of avoidable emissions.
Grounded in: Research Frontier 4 · Gudipudi et al. · Nature Sustainability · 2025
In development
🌱
SDG Synergy & Tradeoff Tracker
Maps co-benefits and conflicts between climate action and sustainable development goals across sectors — supporting integrated policy design for cities and corporations.
Based on: Warchold A, Thapa P, Kropp JP et al. · Sustainable Development · 2022
In development
📐
Pathway Alignment Screener
Assesses whether a corporate decarbonisation plan is consistent with an industry-specific 1.5°C pathway — grounded in RF2 sector modelling and independently verifiable.
Grounded in: Research Frontier 2 · Gudipudi et al. · Nature Sustainability · 2025
In development
Work with the Lab

Three ways in

Whether you're a city mapping your emissions, a corporation building a credible pathway, or a researcher looking to collaborate — the 'G' Lab has a door open for you.

🏙️
Cities & Regions
Get your emission profile mapped
The Lab can produce spatially disaggregated emission inventories for your city — compatible with corporate Scope 3 reporting frameworks and science-based targets.
Explore for Cities →
🏭
Corporations
Build a credible decarbonisation pathway
Access RF2 industry-specific pathways, RF3 decomposition analysis of your emission history, and RF4 residual emission benchmarks — the science behind a defensible net-zero claim.
Explore for Corporations →
🔬
Researchers
Collaborate with the group
The 'G' Lab welcomes collaboration on emission accounting, urban carbon modelling, and the science-policy interface. Write to us if you want to collaborate.
Prof. Kropp's ORCID ↗