Related Experiment Video
Updated: Sep 17, 2025

Split Point Analysis and Uncertainty Quantification of Thermal-Optical Organic/Elemental Carbon Measurements
Published on: September 7, 2019
Large differences between UK black carbon emission factors
Adam Brighty1, Iain Staffell2, Helen ApSimon2
1Centre for Environmental Policy, Imperial College London, London, UK. a.brighty21@imperial.ac.uk.
Black carbon (BC) emissions are highly uncertain due to a lack of standardized measurement. This study found significant discrepancies between two major UK emission databases, highlighting the need for alignment.
Area of Science:
- Environmental Science
- Atmospheric Chemistry
- Climate Change Research
Background:
- Black carbon (BC) is a significant air pollutant linked to climate warming and adverse health effects.
- Current BC emission estimates are highly uncertain due to the absence of standardized measurement techniques.
- Evaluating discrepancies in BC emission factors is crucial for accurate climate and health impact assessments.
Purpose of the Study:
- To compare and evaluate two UK-based black carbon (BC) emission factor databases: the National Atmospheric Emissions Inventory (NAEI) and the GAINS model database.
- To identify the extent of disagreement between BC emission factors from NAEI and GAINS across various fuel consumption (1A NFR code) sources.
- To assess the variance in BC emissions estimates derived from different databases and activity data.
Main Methods:
- Utilized NAEI and GAINS model databases for BC emission factor comparisons.
- Focused on the 1A (Fuel Consumption) NFR code, representing major BC-emitting activities in the UK.
- Compared NAEI reference values against a range of GAINS emission factors (low, medium, high) and analyzed PM2.5 and NOx emission factor overlaps.
Main Results:
- The NAEI BC emission factor fell outside GAINS ranges for 64% of the analyzed 1A sources, particularly in industrial combustion.
- Disagreements for PM2.5 (26%) and NOx (46%) emission factors between databases were less frequent than for BC.
- Complementary BC emissions estimates using NAEI activity data showed highest variance in industrial, domestic, and agricultural combustion.
Conclusions:
- Significant discrepancies exist between UK BC emission factor databases, especially for industrial sources.
- The variability in BC emission factors necessitates further investigation into underlying methodologies.
- Aligning BC emission factor databases is essential for improving the accuracy of climate and air quality models.
Related Concept Videos
Factors Affecting Respiration
Factors Affecting Activity Coefficient
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
The Carbon Cycle
Chemical Factors Affecting Respiration Centers
CO2 has a potent influence on respiration and is strictly regulated....

