All our field measurements pointed to high emissions of particulate matter just before and during ignition (see P2A). Material released from wood escapes to the atmosphere when it doesn’t pass through a flame. We are exploring how to mitigate these pre-ignition events.

2024 Illuminating onset of pyrolysis & ignition. Identifying conditions that promote ignition, and decrease pre-ignition emissions. Fun times at Edinburgh fire safety lab. (Flynn, Morrisset, Hadden, Bond – submitted to Proc Combustion Inst.)
2024 Predicting time-resolved wood-burning emissions. Model is a hybrid of mass loss predicted with a “standard” pyrolysis model and machine-learning outcomes of measured data. (Fawaz, Gollner, Bond – in press at Biomass & Bioenergy)
2022 Chemical composition of pyrolysis emissions with an Aerodyne Mass Spec. Composition does vary between woods and burning conditions but is relatively constant throughout the burn. (Avery et al, ACP)
2021 Pyrolysis principles explain time-resolved organic aerosol release. Wood burning rates are predictable before ignition. Seven wood types & three temperatures. (Fawaz et al., ACP)
2020 Predicting aerosol precursors from pyrolysis. Much investigation is either “fast” or 1-d pyrolysis. We applied pyrolysis reactions to in a 2-d wood model, did some fitting, and the prediction is OK. (Fawaz, Lautenberger, Bond – Fuel)

My students have built portable emission equipment and measured real-time emissions in hundreds of homes. We’re not doing this anymore because I think we learned what’s possible to learn, and I’m trying to solve the pyrolysis problem.

2022 Appliances for Cooking, Heating, and Other Energy Services – book chapter by me and Zach Merrin in Handbook of Indoor Air Quality (Springer)
2019 In-use emissions in Yunnan, China – coal and other materials. Shows importance of startup phase. (Thompson et al, ES&T)
2019 In-use emissions in Nepal and Tibet – wood & agricultural residue. Black carbon emission factors are bounded; organic carbon emission factors can get quite high. (Weyant et al, ES&T)
2017 Seasonal uses of fuel in Far-West Nepal. Measurements over the year showing importance of non-cooking uses. Tough field study, by the way (Lam et al, ERL).
2013 Kerosene lamp policy brief from Brookings (Jacobson, Bond, Lam, Hultman)
2012 Kerosene lamps Simple kerosene lamps have very high BC emission rates (Lam et al, ES&T)
2012 Pattern matching (PaRTED). We crunched real-time combustion emissions into patterns, showing why lab and field measurements were so different (Chen, Roden, Bond, ES&T)
2009 Cooking stoves in laboratory vs field. In-use cookstoves don’t behave like lab stoves. Some improved stoves are better than unimproved stoves; some aren’t. 3 years of measurements with partners at AHDESA & TWP. (Roden, Bond & lots of others – Atmos Env)
2006 Field box in Honduras. Emission factors, absorption and scattering from real cooking fires. First field measurements I know of that did real-time particles. (Roden, Bond, Conway & Osorto – ES&T)

We dove into brick kilns for a while. Measuring & mitigating is a sector-wide effort. We worked out the measurement procedures, developed the equipment, wrote protocols, and passed the work on to groups like ICIMOD and the Clean Air and Climate Coalition. This was a great collaboration with Greentech, Enzen, Clean Air Task Force.

2020 Kiln measurements in Colombia – report for CCAC; never put into journal though.
2016 Brick kiln measurement guidelines – led by Cheryl Weyant for CCAC
2015 Brick kiln emission sampling protocol – led by Ryan Thompson & Cheryl Weyant for CCAC
2014 Brick kilns in South Asia. Emission factors from a few kinds of kilns. First black carbon measurements from these.  (Weyant et al – ES&T)
2012 Brick Kiln Performance Assessment – Roadmap for Cleaner Production. Extensive report for Shakti and ClimateWorks led by Greentech; we did the environmental impact part.

I worked on emission inventories and some unusual sources didn’t have emission measurements. Now we have more.

2016 Natural gas flaring. Emission factors from flares in the Bakken region, flying Paul Shepson’s little plane through plumes. (Weyant et al – ES&T)
2009 Diesel emission factors from 88 vehicles in Bangkok. Climate-relevant properties– EC content, absorption, and water uptake. Partnership with AIT and World Bank (Subramanian, Bond et al. – ES&T)
2006 Oil & gas boiler that replaced the lignite stoker shows net effect of technology switch on emission of absorption and particle number (Bond, Wehner et al., Atmos Env)
2002 Chunk coal burning in a few different stoves – bituminous, lignite, formed briquette; emission factors, absorption, particle size distributions. (Bond, Covert et al. – JGR)
1999 Light absorption by particles from a lignite boiler in Leipzig. Very little absorption – surprised me & led to fascination with aromaticity. Collaboration with Inst for Tropospheric Research. (Bond, Wehner et al. – ES&T)
1996 Catalytic combustion of natural gas – MS degree work in Bob Dibble’s lab. (Bond et al, Combustion Symposium)

Emissions from households – especially from solid-fuel burning – are atmospherically important. However, reductions aren’t as trivial as a technology swap; contextual limitations and human dimensions are at work. 

2023 Reduction potentials for household energy emissions. We borrowed terminology from renewable energy to describe feasible fractions of emission reductions. Underlying dataset is high-resolution for India. (Nick Lam et al – ERL, Kirk Smith tribute issue)
2022 Conceptual framework for evaluating cooking systems. Came out of ISO standards work prompted by differences between lab and field emissions. (T Bond & ISO colleagues – ERL, Kirk Smith tribute issue)
2020 Health effects of cleaning up household energy in India. Complete transition reduces life loss by 25%; there are other practical limitations to transition described in the high-res emission paper of 2023 (L Conibear et al – ERL)
2016 Emissions from residential combustion II. Plausible emission reductions from cooking and heating stoves – depending on whether folks are near electricity or forest. (Ekbordin Winijkul and Bond, Atmos Env)
2016 Emissions from residential combustion I. We used nightlights and forest land combined with population to distribute household emissions. (Ekbordin Winijkul, L Fierce and T Bond, Atmos Env)

Vehicles are a great demonstration of a system that includes infrastructure and people in addition to technology. I summed up the evolution of thought in a “Behind-the-Paper” post to accompany the 2019 paper.

2019 Climate & health impacts of freight (i.e. goods movements over long-haul and delivery distances) through 2050. Considers mode switch, superemitters, urban sprawl – not electrification though. Estimates long-lived and short-lived climate forcing and mortality (Liang Liu et al., Nature Sustainability)
2015 Emission projections for USA trucks & rail, considering mode switching by commodity and network congestion (Liang Liu et al., ES&T)
2014 Effectiveness of mitigation measures for global fleet of cars and trucks. We compared superemitter policy vs scrappage using Monte Carlo examination of robustness (Fang Yan, Bond & Streets, ES&T)
2014 Uncertainty in on-road projected emissions propagating unknowns in fleet parameters through stock model. Retirement rate matters and its dependence on income is uncertain. (Fang Yan et al., Atmos Env)
2011 Projected emissions for on-road vehicles using a technology stock model consistent with global scenarios. Superemitters and Africa are important in the near future. (Fang Yan et al., Atmos Env)

I’ve gotten back into residential airflows and managing indoor IAQ. Most of my work on this topic was done at Ecotope with Larry Palmiter a long time ago. The old stuff has never been published but I still remember how it goes. Not linked here but I have the PDFs.

2021 Proximity, Confinement, and Interventions. Everyone had a COVID paper and this was mine. We proposed a way of characterizing spaces (rebreathed volume) that could be done before any pandemic and compared how many interventions would affect infection probabilities. SI is 37 pages. Calculation-heavy because what else was there to do? (Bond et al. ES&T)
1995 Interaction of mechanical systems & natural infiltration. Source of the “0.5 rule.” (Palmiter & Bond, AIVC conference)
1991 Measured & modeled infiltration. 472 homes in the Pacific Northwest with PFT measurements and LBNL infiltration model. (Palmiter, Brown and Bond – ASHRAE Trx)
1991, 1994 Measured and modeled infiltration Time-resolved tracer gas measurements compared with models (Palmiter & Bond, 7 homes, 2 reports for EPRI)

People spend a lot of time at home, but don’t have many ways to control health stressors where they live. Why not and what can we do about it?

2024 Moving the Needle on Home Health. A social-problems take on creating integration from fragmentation. (Ambord, Bond, Francisco, Magzamen; submitted to Environmental Health Perspectives)

Set out to answer the question “How much climate impact might we reduce by mitigating black carbon sources?” (And how well do we know that answer?) 180 journal pages, 4 years from start to finish. Open access at JGR.

2013 Bounding-BC Black carbon, all its effects, and all its sources. A couple things people could work on (instead of, say, mixing state, or running the models again and again with lousy inputs)
– Effect of organic carbon on clouds. Determines whether black carbon reductions are worth doing for a particular source.
– Is there really more absorption in the atmosphere than in the models? Or is it just that we don’t know how to distinguish BC from dust in AERONET obs? If there’s a lot of BC, what’s the source?
– Figure out some clever ways to constrain forcing by mixed-phase and ice clouds. Wild card.

Emission inventories are tabulations of how much is emitted, where, and from what. Emission rates can vary vastly depending on the technology used to burn. We added estimates of technology used to global inventories; before this body of work, people often used sector-wide emission factors. I worked a lot with Dave Streets at Argonne.

2022 Aerosols and precursor gas emissions – book chapter by me and Cat Scott in Aerosols and Climate edited by Ken Carslaw. All inventories, not just black+organic carbon.
2019 Constrained USA BC inventory for 1960-2000 using COH measurements and other inputs. Diesels must have been a lot more polluting – before there were measurements. (Tianye Sun et al, JGR).
2014 End of the age of aerosols SO2+BC importance dwindle in comparison to CO2. (Smith and Bond, ACP)
2007 Historical biofuel consumption Country-specific estimates of biofuel use since 1850, considering drivers beyond population only. Needed for the historical BC/OC inventory. (Fernandes et al, Global Biogeochem Cycles)
2007 Historical BC/OC emissions Black & organic carbon since 1850. We did the best job we could at constraining technology development and emission factors using old reports, smoke measurements, and commodity production. (Bond & lots of group members, Global Biogeochem Cycles)
2004 Future emissions of black & organic carbon. Estimated  technology improvement and penetration leading to BC/OC plateau in the near future. (Streets, Bond, Lee and Jang – JGR)
2004 Global emission inventory of black & organic carbon with technology basis. Really long paper but gives a combustion background for why sources emit (or don’t emit) black and organic carbon. (Bond, Streets et al. – JGR)
2001 Black carbon emissions in China. Technology-based emission inventory. This is when I started a comprehensive search for emission factors. (Streets, Gupta et al. – JGR)

We provided black & organic carbon emission inventories that were used in IPCC AR5 and AR6. Those products are reported in inventory collection papers. I don’t do this work anymore because the collection work gets supported and cited but the development generally doesn’t.

How much light do particles absorb and scatter (per mass)? This information helps model particles’ effect on sunlight.

2011 Absorption change with RH Measured growth of absorption with RH. Biomass aerosol increases its absorption by a factor of 2. (Beni Brem, Francisco Mena et al. – AS&T)
2010 Absorption by wood organic carbon (OC) Measured spectra of aerosol from wood pyrolysis. Much OC is not water-soluble, but methanol works. (Yanju Chen and Bond – ACP)
2007 Brown carbon color Spectra of yellow and brown carbon. Toyed with different theories to explain the spectra. (Haolin Sun, Biedermann, Bond – GRL)
2006 Limitations in absorption Probable range of absorption amplification by coated particles and varying mixing states. (Bond, Habib & Bergstrom – JGR)
2006 Optics Review Review of why light is absorbed by soot particles, and how much. Another long one. (Bond & Bergstrom, AS&T) ** Inquire about Annotated Version because the tables got messed up. AAAR Outstanding Publication Award, 2017
2001 Spectral dependence of light absorption by carbon particles. Black to brown to yellow colors of carbon particles, and hypotheses about causes. (Bond, GRL)

Black carbon warms the climate system and might be considered in mitigation actions. The Climate and Clean Air Coalition was initiated in 2012.

2011 Metric for short-lived pollutants, especially black carbon. Use energy added per emission, since it’s just a pulse anyway. Shows atmosphere & snow contributions to warming/cooling. (Bond, Zarzycki, Flanner, Koch – ACP)
2007 Why not black carbon? Reasons why aerosols don’t end up in climate policy; reasons why those reasons aren’t supportable (Bond, ERL)
2005 Can black carbon save us from global warming? Policy comment on black carbon & climate, including estimate of direct GWP. Nearly 20 years later, I think the numbers haven’t changed much. (Bond & Sun, ES&T)
2004 Residential fuel emission impact on climate forcing. Combined GWP including black and organic carbon. I think this was the first published GWP for particles (Bond, Venkataraman & Masera – Energy Sust Dev)
Journal papers aren’t the way to reach decisionmakers. I also testified in Congress a couple of times. 

I’m not an instrument developer. I just like to know what I’m measuring.

2014 Carbon in rainwater Comparison of methods for carbon in precipitation – because we’re not very good at quantifying carbon removal. Be careful when using filters. (Alex Torres Negron et al. AS&T)
If anyone’s interested, we also have 2 years of measured event-based wet deposition using the methods we sorted out, which will probably never be published because reviewers expect us to solve the whole problem in a single paper.
2009 Nephelometer truncation corrections Need to use size distributions to calculate error when measuring brown carbon (Bond et al. AS&T)
2008 Physical basis of thermal-optical analysis (OC-EC analysis). Express the whole mess as a matrix reactor equation. How to live with an underdetermined system. (Poonam Boparai, Lee & Bond AS&T)
2007 Beads on fiber filters Absorbing liquid particles on filter samples alter absorption. (R Subramanian, Roden, Boparai, Bond AS&T)
1999 Calibration of light absorption measurements: The infamous PSAP calibration paper. (Bond, Anderson and Campbell AS&T)
1998 Quantifying emissions of light absorption: Measure light absorption at the source. (Bond, Charlson and Heintzenberg – GRL)

I use simulations at micro-scale and macro-scale to get to a parsimonious form, or to figure out what matters.

2021 Model-resolution discrepancy for comparing grid averages with point-source measurements. (Tianye Sun, Zarzycki and Bond, Atmos Env)
2018 Is cloud radiative forcing linear with emission rate? Only where emissions and concentrations are relatively low (Yanju Chen et al., JGR)
2017 Plume-exit modeling: We proposed plume-exit as appropriate for reporting emission characteristics and identified in-plume processes that affect cloud condensation activity (Francisco Mena Gonzalez, Riemer & Bond, ACP)
2017 Reduced mixing state – parameterization of cloud condensation activity and light absorption. (Laura Fierce, Riemer and Bond, BAMS)
2016 Diversity in composition at particle scales affects overall light absorption. (Nature Communications; Laura Fierce et al.)
2014 CCN sensitivity No clouds from diesel engine particles until high supersaturation occurs. Then it depends on condensation of secondary material. (Laura Fierce, Riemer & Bond)
2010 Vertical distribution. Black carbon altitude creates a 25% uncertainty in direct forcing. (GRL; Colin Zarzycki and Bond)
2007 Future climate forcing by individual source sectors. (Koch, Bond, Streets, Unger – ACP)
2007 Forcing by individual sectors Present-day climate forcing by individual groups of sources, rather than chemical components. (Koch, Bond et al.)

We (that is, Sagar Rathod and I) did with combustion-iron what I’d done with black carbon – inventories and optics. These products went directly into models run by partners at Cornell – there are lots more papers from them.

2023 Constraining iron emissions: used several comparisons to give a best estimate of combustion iron emissions with uncertainties. (Rathod et al, Submitted to JGR)
2022 Atmosphere & ocean responses to combustion iron, using the mineral form. Overall question: could response to combustion iron be noticeable in atmosphere (radiation) or ocean (biology)? Answer: probably not, even with uncertainty (Rathod et al., GRL)
2022 Earth, Wind, Fire and Pollution – Overview of impacts on ocean biogeochemistry. This one includes phosphorus in addition to iron (Hamilton et al., Ann Rev Marine Sci)
2020 Global inventory of iron particles emitted from combustion, divided into emitted minerals in which the iron appears. The mineral form affects absorption & solubility. (Rathod et al., JGR)