The staff of the Institute for Clinical and Economic Review, or ICER, are known as the nerds of the drug industry: bespectacled killjoys who emerge a few times a year to scold drugmakers for pricing their latest cancer or MS advance far beyond reason.
But last year, its staff sat down and concluded a forthcoming treatment was worth up to $3.9 million — more than any medicine in history, more than a 45-year supply of Humira, the autoimmune drug often held up as an emblem of America’s runaway drug spending.
It was a testament to the power of a new class of gene therapies to deliver something pharma so rarely does: Genuine cures. The treatment, approved last week as Lenmeldy, may allow some babies born with an ultra-rare neurodegenerative disease called metachromatic leukodystrophy, or MLD, to grow up and live essentially normal lives.
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The surface of the Moon is covered with a layer of loose rocky material, including micron and submicron-sized dust particles. This regolith has been formed and remains continually reworked, by the intermittent impacts of comets, asteroids, meteoroids and the continual bombardment by interplanetary dust particles (IDPs). All planetary bodies in the inner solar system are continually bombarded by IDPs originating primarily from asteroid collisions and cometary activity. Thick atmospheres protect Venus, Earth and Mars, ablating the incoming IDPs into ‘shooting stars’ that rarely reach the surface. On the contrary, the surface of airless planetary bodies are directly exposed to IDP impacts. The effects of meteoroids bombarding the lunar surface, especially their contribution to sustaining the tenuous lunar atmosphere, have been recognized since the Apollo era, but there are still large uncertainties in our knowledge about the variability of their flux, size and speed distributions [1]. In addition, the solar wind plasma flow and solar ultraviolet radiation also reach the surface generating a near-surface plasma environment that can lead to charging, mobilization and transport of the lunar fines.
Dust poses risks to human presence or the long-term remote operation of astronomical telescopes on the lunar surface. Dust particles damage spacesuits [2], cover optical surfaces [3–5] and degrade the performances of thermal radiators and solar panels [2]. Lunar dust in human living quarters could lead to health risks when inhaled by astronauts [6].
Below we discuss the effects of the IDP influx (§2), the properties of the secondary ejecta particles they generate (§3) and the near-surface plasma effects on the lunar regolith (§4), as these all represent a potential hazard for establishing permanent human habitats, and to use the unique opportunity the Moon offers to deploy astronomical observatories [7,8]. We offer our assessment for ranking the potential risk these processes represent (§5).
The surfaces of airless bodies near 1 AU are directly exposed to high-speed () micrometeoroid impacts, particles with characteristic radii of dominating the mass flux of [9]. The most recent estimate of the cosmic dust input into the Earth’s atmosphere is () tons per day [10]. The mass flux of meteoroids impacting the lunar surface is about 30 times smaller due to the Moon’s smaller size and reduced gravitational focusing, resulting in an average total deposition rate of () tons per day [11]. IDPs arrive at the lunar surface with a characteristic speed of [11]. Figure 1 shows the size, , and speed, , distributions that are assumed to be independent, hence . The IDP sources impacting the Moon at high latitudes remain largely uncharacterized due to the lack of optical and radar observations in the polar regions on Earth [13]. High-latitude sources could have very large impact speeds in the range of [14,15], hence they are expected to have a significant effect on the lunar surface, including the removal and burial of volatile deposits in the lunar polar regions.
IDP impacts will excavate craters on exposed surfaces. One of the goals of NASA’s Long Duration Exposure Facility mission (LDEF) was to survey the interplanetary and Earth-orbital dust populations [16]. LDEF was placed in low-Earth orbit (LEO) by the space shuttle Challenger in April 1984, and retrieved by the space shuttle Columbia in January 1990, orbiting for 5.77 years in the altitude range of 331–480 km. After retrieval, a set of 761 craters was identified on a zenith-facing aluminium alloy panel, with diameters in the approximate range of [17]. Each micrometeoroid impact generates a dent, with a radius and depth set by its mass, speed and composition, degrading the performance of optical surfaces at an approximate rate of 0.01%/year at 1 AU distance from the Sun, with large possible fluctuations due to the stochastic nature of impacts. In the first approximately six months of operations, the Webb telescope’s primary mirror, with a total surface area of about , was hit five times, without generating any noticeable degradation in its performance [12]. During the predickted lifetime of 20 years, the Webb telescope’s primary mirror is expected to steadily accumulate damages that only minimally degrade its performance, neglecting additional damages by the rare and hard-to-predict larger () IDPs. Similar degradation is expected for optical telescopes on the lunar surface.
In addition to direct damage, IDP impacts generate secondary ejecta particles, lofting them to high altitudes (), some even escaping the Moon. The bound ejecta particles form a permanently present dust cloud engulfing the Moon that was identified during NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) mission [18]. LADEE was launched in September 2013, it reached the Moon in about 30 days, and continued with an instrument checkout period of about 40 days at an altitude range of 220–260 km, followed by approximately 150 days of science observations period at a typical altitude range of 20–100 km. LADEE followed a near-equatorial retrograde orbit, with a characteristic orbital speed of . It carried the Lunar Dust Experiment (LDEX) that was designed to explore the ejecta cloud generated by sporadic interplanetary dust impacts, including possible intermittent density enhancements during meteoroid showers, and to search for the putative regions with high densities of dust particles with radii µm lofted above the terminators [19]. LDEX was an impact ionization dust detector that measured both the positive and negative charges of the plasma cloud generated when a dust particle struck its target. The amplitude and shape of the waveforms (signal versus time) recorded from each impact were used to estimate the mass of the dust particles. The instrument had a total sensitive area of , gradually decreasing to zero for particles arriving from outside its dust field-of-view (FOV) of off from the normal direction [20]. The measured fluxes indicated that the Moon is engulfed in a permanently present, but highly variable dust exosphere (figure 2). The density of the dust exosphere, compared with our best models of the incoming primary meteoroid flux, is lower than expected. Based on LDEX observations, the total ejecta production rate on the Moon is of the order of , indicating a mass yield [11], 2–3 orders of magnitude smaller than the icy Galilean moons of Jupiter [23].
The vast majority of the ejecta particles are launched into a narrow cone angle normal to the surface with speeds below the escape speed from the Moon (), hence following ballistic trajectories and returning to the surface [24]. LDEX observations enable us to estimate the average lunar dust ejecta density distribution above the Moon, and the rate at which this exospheric dust rains back onto the lunar surface. Near the equatorial plane, the burial rate is estimated to be approximately of lunar regolith, with a cumulative size distribution index of , that is redistributed due to meteoritic bombardment, a process that occurs predominantly on the lunar apex hemisphere [25]. This burial rate is rather modest; however, it does not include any contribution that initially slow particles, which did not rise to the orbital altitude of LADEE, might contribute.
Additional sources of damage are the fast secondary ejecta particles that have speeds above the lunar escape speed, generated at shallow angles [26]. They dominate the generation of micro craters with diameters below observed on lunar rocks [27,28]. The cratering rate of these small pits, compared with the predictions based on in situ measurements of micrometeoroids in space, indicate a flux of fast ejecta of particles with radii [9], that generates a negligibly slow surface degradation rate due to cratering. However, high-speed hits can generate significant impact charges and electromagnetic pulses and can destroy sensitive electronics [29].
Compared with direct IDP impacts (§2), or impacts/burial by secondary ejecta particles (§3), perhaps the biggest concern for Moon-based astronomy is electrostatic dust charging, mobilization and transport, which is expected to dominate the near surface () dust environment [30,31]. The Moon has no global magnetic field and only a tenuous exosphere, hence, its surface is directly exposed to the solar wind plasma flow, the Earth’s magnetospheric plasma environment and solar ultraviolet (UV) radiation, resulting in electric charging of the regolith that varies in space and time [32]. Electrostatic charges are expected to accumulate on human and robotic exploration systems, causing potential issues for crew safety and for the performance of scientific instruments and equipment [33–36].
Electrostatic processes on the lunar surface were first indicated by Apollo-era observations. The Lunar Horizon Glow (LHG), 30 cm above the surface was recorded shortly after sunset by the Surveyor landers (figure 3). The LHG is likely due to sunlight scattered off a cloud of dust particles with radii of a few µm that are lofted by electrostatic forces near the terminator [37–40]. The height of the LHG is consistent with a recent observation by the Chang’E-3 rover of fine dust deposits on lunar rocks up to a height of cm [41].
The unexpected signals of the Apollo 17 Lunar Ejecta and Meteorites Experiment (LEAM) deployed on the lunar surface have been suggested to be due to low-speed , highly charged dust particles with the rates spiking near sunset and sunrise [42]. However, different LEAM datasets showed no rate enhancement associated with terminator crossings and indicated that any enhancements were likely caused by rapid temperature changes rather than lofted dust [43]. Similarly, high-altitude dust possibly lofted through electrostatic mechanisms indicated from the Apollo astronauts’ sketches [44,45] and images from orbit [46,47] remained controversial. Such a dust population was not confirmed by the remote sensing observations by Clementine [48] and LRO/LAMP [49], or by the in situ measurements from LADEE/LDEX [21,50], contrary to a competing analysis [51]. These putative near-surface dust mobilizations might represent only modest dust fluxes, as opposed to dust mobilization due to human activities (figure 3), but they are acting continually for long periods of time, and without easy mission design solutions to mitigate their effects.
Through the decades following the Apollo missions, the processes responsible for the initial lift-off of dust particles remained poorly understood, even though a number of models [52–54] and laboratory experiments [55–58] were dedicated to this issue and succeeded in explaining the subsequent dynamics of charged dust particles in plasma sheaths. Recently, the recognition of the roles micro-cavities play in surface charging led to a better understanding of particle lift-off from surfaces due to plasma effects, the so-called patched charge model [59]. The model, verified by a series of experiments (figure 4) [60–66], is based on the emission and re-absorption of secondary electrons, generated by impacting energetic () electrons, ions or UV photons. As opposed to the case of a flat surface, secondary electrons can remain trapped in cavities that form between dust particles, generating a potential difference of the order of 2–3 V, due to the typical energy of secondary electrons. This potential difference for a photoelectron plasma sheath on the Moon, with a daytime characteristic shielding thickness of the order of 1 m, generates an electric field to . In a cavity, the same potential difference develops across characteristic distances of perhaps 10 to , generating surprisingly large electric fields of the order of , accompanied by highly enhanced, both positive and negative surface charge density distributions. The combination of complex electric fields and charge density distributions leads to ‘Coulomb explosions’, which break the cohesive forces between dust particles, and lead to the initial lift-off of charged grains (figure 4) [59]. Contrary to the expectations of positively charged particles, the emergence of highly negatively charged particles from a rough surface under UV illumination has been verified in laboratory experiments [60] and successfully explained using computer simulations [67].
The lunar soil samples, returned by the Apollo missions, have a size range of to 1 cm and an approximately log-normal size distribution with a typical maximum in the range of [68,69]. The small optical dust detectors on Apollo 12, 14 and 15 [70], each placed 1 m above the surface, indicated a combined long-term dust accumulation rate of the order of [71]. The Chang’E-3 lander’s Sticky Quartz Crystal Microbalance (SQCM), at a height of 1.9 m above the lunar surface, reported a dust accumulation rate of about [72]. Without knowing the initial speed and velocity distribution of the dust grains launched from the surface, it remains an open question how the dust accumulation rate changes with height above the surface. Assuming that these were similar at all the Apollo and the ChangE’3 landing sites, and using the observations at these two distinct heights to determine an approximate scale height, assuming that for dust deposition, indicates , and an accumulation rate on the surface. If the characteristic radius of the mobilized dust particles is , the coverage of an exposed flat surface () by dust is about 15%/y, if a = the coverage is 3%/y, and if , the coverage reduces to 1.5%/y.
The size and initial speed distributions of lofted particles were measured in laboratory experiments (figure 4), establishing an expected lofting rate, if extrapolated to lunar conditions, of 1– [61]. While in the tabletop laboratory experiments this initial rate dropped in minutes due to a lack of reciprocal dust transport in/out of the small crater holding the lunar simulant, it is expected that the dust lofting rates on the lunar surface could be sustained over geological timescales. The typical lift-off speed of in these experiments indicates that the particles in the typical size of 10 to could reach heights of on the lunar surface. If particles are lofted at a rate of they generate a surface coverage rate of nearly 30% per day of landing particles. Some of the deposited grains could be subsequently removed by the very same processes, but dust mobilization from a smooth surface covered by a single layer of dust is expected to be much less efficient. The laboratory experiments cannot possibly reproduce lunar vacuum, UV radiation and plasma conditions, or the properties of the regolith, hence, the efficacy of plasma and UV-induced dust charging, mobilization and transport on the lunar surface remains an open issue. It is perhaps still encouraging that the rough estimates based on the combined Apollo [71] and ChangE’3 [72] in situ measurements are of similar magnitude as the laboratory results [61]. These processes could represent a significantly large enough hazard to warrant a combination of in situ measurements.
Dust on the lunar surface represents a variety of hazards and its safe and effective mitigation requires detailed, yet to-be-fully developed, engineering approaches. The lunar dust is extremely abrasive, similar to broken glass, it ruins friction-bearing surfaces, seals, gaskets, optical lenses, windows, degrades thermal radiators, solar panels and causes dangerous physiological effects on the tissue in human lungs [2].
Solar panels and optical devices on the lunar surface will lose performance due to the accumulation of dust particles on their surfaces. However, it is possible that dust accumulation can reach equilibrium due to the accompanying processes that can lead to concurrent dust removal. The Apollo Lunar Laser Retroreflectors deployed during Apollo 11, 14 and 15 are still operating after well over 40 years; however, the magnitude of the return signal has decreased by a factor of 10 to 100 since the arrays were deployed [3–5]. Even at the very start of their use, the strength of the return signal was about 10% of the expected value, based upon an analysis of the ground stations and the retroreflector arrays. A deposit of lunar dust on the front faces of the reflectors is the most likely reason, other causes have also been suggested, for example, the darkening of the glass material due to UV and/or particle exposure, micrometeoroid bombardment, or change in the thermal properties due to dust, UV and or plasma exposure. The dust may be due to secondary ejecta from micrometeorite impacts in the vicinity, electrically levitated dust and/or dust from the lift-off of the Apollo lunar module [4].
Most open questions about near-surface dust mobilization could be answered by precursor missions delivering small dedicated experiments to the lunar surface. For example, the size and speed distributions of electrostatically levitated dust could be measured on the surface [73,74]. A complementary measurement of the dust coverage as a function of height could be measured by the optical transmission changes of a series of glass plates [75] or quartz crystal microbalance set-ups [72].
We focused on the naturally occurring dust hazards, but rocket firings during landings and take-offs, pedestrian and motorized vehicle traffic, for example, will liberate copious amounts of dust, representing a potential hazard for the safe and optimal use of optical platforms [76]. These, however, could be mitigated by careful mission design using distant landing/take-off sites, minimizing any traffic near installations and by including shutters and covers over sensitive surfaces that can be deployed during critical periods, as needed. Site selections for the various scientific installations, and their long-term optimal use, will require international agreements and cooperations [77].
This article has no additional data.
We have not used AI-assisted technologies in creating this article.
M.H.: formal analysis, funding acquisition, investigation, writing—original draft; X.W.: investigation, methodology, writing—review and editing; J.R.S.: investigation, methodology, software, visualization, writing—review and editing.
All authors gave final approval for publication and agreed to be held accountable for the work performed therein.
We declare we have no competing interests.
The authors acknowledge support from NASA's Solar System Exploration Reserach Virtual Institute (SSERVI): Institute for Modeling Plasmas, Atmopsheres, and Cosmic Dust (IMPACT).
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Crossref, ISI, Google ScholarIt's a typical weekday in Beth Acton's Montreal home. Two of her children are at school, but another, 12-year-old Connor, is asleep upstairs under a pile of Squishmallows.
Acton logs on to an app on her phone to report Connor's latest absence to his school, something she's been doing regularly since the fall of 2022, which was the second time Connor got COVID-19.
"He is ill very, very frequently. You know, kind of catches anything that's going around," she said. "He sometimes just can't even complete the school day."
Connor, who is struggling to pass his Grade 7 year, has not been diagnosed with a chronic condition, but his delicate health has meant he's missed most of the last four weeks of school.
Connor's case is extreme, but exclusive data compiled by CBC News suggests he is far from alone in missing considerably more school than before the pandemic. In multiple districts across the country, rates of chronic absence — the percentage of students who miss at least 10 per cent of the school year, or two full days a month — are up significantly.
There is no data as to why. Interviews with experts and those affected suggest there are many reasons — from illness to bullying to a lack of support services — which vary by district and even by school.
CBC's analysis found more children missing school in every district or province that was able to provide data compared with pre-pandemic. In six districts, the rate of absence or chronic absence more than doubled. In Newfoundland and parts of New Brunswick, more than half of high school students are chronically absent. But the most significant increases were among elementary students.
It's an issue that's flown under the radar in Canada because there is no publicly available national data on how many kids miss large amounts of school or the reasons why.
This is not the case in both the U.S. and the U.K., where the number of students missing significant amounts of school is being called a national crisis.
The lack of data makes it almost impossible for policy-makers to get a sense of the scope of the problem and take action, says Maria Rogers, a child psychologist and Canada Research Chair in Child Mental Health and Well Being at Carleton University.
"If we don't have the data to show that our children are missing tremendous amounts of school, far more than they have in the past … then it's easy to look the other way," she told CBC News.
Children who attend school regularly generally have better emotional health, better relationships with teachers and stronger social connections, Rogers added.
"We know that academic achievement, broadly speaking, is one of the top predictors worldwide of a healthy adulthood."
It's possible, experts say, that the pandemic has had a lasting impact on attitudes toward school attendance. Some parents, more likely to be working from home themselves, may be keeping their kids home with milder symptoms for longer than they would have pre-pandemic.
For others, the extended periods of online school has shown they don't always need to be physically present to keep up with their work. And then there are the kids who began their school experience during the pandemic.
Rogers says there's just been this normalization of school attendance problems, a change she's noticed in her own home. "Even my own kids will sometimes say, 'Well, I'll just check Google classroom,' right?"
In the U.K., research from the Centre for Social Justice found one in five students were persistently absent in spring 2023, which represents a 60 per cent increase compared with pre-pandemic. The think tank also found the rate of severe absence among vulnerable children, or those receiving free school meals, was triple the rate of those not eligible for the free meal program.
In the U.S., Stanford University professor Thomas Dee compiled and analyzed data on chronic absenteeism in 40 states. His research, which compared 2018-19, the last pre-pandemic school year, with 2021-22, found an increase in every state. A large majority of states collect annual data on chronic absenteeism and use it as a performance indicator mandated by the federal Every Student Succeeds Act, Dee wrote in his research paper.
In Canada, there is no such body mandating the collection or publication of this data. As a result, absence data is collected inconsistently, if at all, by provinces or territories, school boards or individual schools, using different indicators that are not comparable across jurisdictions.
CBC News asked 41 Canadian school districts with more than 30,000 students for rates of chronic absenteeism for both pre- and post-pandemic school years. We received complete data from eight districts, two provinces and found publicly available data for two territories. Four additional districts provided data for only one time period, either pre- or post-pandemic. Twenty districts were unable to provide data and eight did not respond to our request by deadline.
In Newfoundland and Labrador, two-thirds of secondary school students were chronically absent in 2022-23, up from just under half in 2018-19, according to figures provided by the province's Department of Education. For elementary students, the rate more than doubled, from 23 to 50 per cent over the same period.
The number of children missing school in the province was already a concern before the pandemic, with the province's child and youth advocate releasing the results of an investigation into it in 2019. It identified learning disabilities, mental health problems for children and their parents, racism, poverty, substance abuse and violence in schools as some of the contributing factors.
Multiple parents in Newfoundland, who did not want to be identified, said in social media messages that their children faced significant bullying that made them afraid to go to school.
Don Coombs, president of the Newfoundland and Labrador Federation of School Councils, says the factors keeping children away are so wide-ranging it's impossible for schools to address them in isolation.
Families, local governments and provincial departments of education and social services must work together to find out why children are missing school and help them, Coombs said, citing bullying as one example.
"Communities have to be involved. People should not feel intimidated to go walk through the doors of the school. It's a place of learning and it has to be a safe and friendly environment," he said.
The interruption of school during the COVID-19 pandemic may have made things worse by further weakening some students' already tenuous connection to school.
"I think once you become disconnected with school, it's hard to reverse," Coombs said. "These children often lose their social connections. You know, they drop behind in the curriculum and … it's hard to catch up."
Without data, it's impossible to know for sure, but from her vantage point as an academic and child psychologist at Carleton, Rogers says it's likely children who were struggling before the pandemic with things like learning disabilities, ADHD or anxiety account for at least some of the post-pandemic increase in absenteeism.
"The research is showing that a lot of those kids did not do well with online learning, so they're now further behind. There's an increased learning loss for some of those children, so you can imagine that that would also make it harder to get back to school," she said.
Staff shortages across the country also made it difficult for districts to provide such students with the help they needed in the classroom, Rogers added.
Fredericton parent Laurel Richmond experienced this first-hand. Her son, now 10, was in kindergarten and Grade 1 during the pandemic. Richmond noticed he was having trouble reading and discussed it with his teacher, who she said took a wait-and-see approach. But as the weeks went by, Richmond became concerned.
"You could see his demeanour was changing. He didn't want to go to school," she said. "He fought me most mornings. He oftentimes had stomach aches, headaches, body aches."
Richmond said her son told her he feels like he's stupid and that everyone seems to get it but he's just pretending to understand what's going on.
Richmond got her son privately assessed and the results showed he had dyslexia (difficulty reading) and dysgraphia (difficulty writing). The school offered some assistance, Richmond said, but did not have anyone with experience dealing with these conditions who could provide the help he needed.
All of this, combined with a disruptive months-long pandemic closure at the end of kindergarten and a bullying situation that was causing her child further anxiety, led to Richmond's difficult decision to pull her son out of the system in Grade 1 and home school. He is now much more confident and reading almost at grade level, she said.
Richmond's district, Anglophone West, saw significant increases in chronic absence at all grade levels
The sense of anxiety Richmond describes in her son is something Rogers sees regularly in her practice as a child psychologist. Mental health deteriorated significantly for everyone since the pandemic, but it's especially true of youth, she said, and it could be one reason they're missing school.
"Some people in my field are calling it a mental health crisis amongst youth worldwide," Rogers said. "We don't have the services to provide to meet those needs either in the community or in the school system."
And then there's illness. Back in Montreal, Acton, a CEGEP teacher, says her department has had to devote permanent classroom space to people writing makeup exams because they've been home sick.
Acton says her eldest son Jacob, who is 15, has told her there are a lot of kids that are absent quite frequently from his Grade 9 class. Acton also says her daughter Tessa who is 9, had a day in December where less than half her Grade 4 class was present.
As for Connor, Acton suspects he has long COVID, but he has yet to get an appointment with a clinic that could make that diagnosis. Acton says she looks forward to having his health challenges resolved so he can get back in the classroom. Every day, she says she feels forced to choose between her child's education and his health.
A new report says the federal government is providing billions of dollars in financial support for the fossil fuel industry, despite measures announced last year to limit certain types of subsidies for the oil and gas industry.
The analysis, released today by the advocacy group Environmental Defence, estimated that Ottawa offered up at least $18.6 billion in support of the fossil fuel and petrochemical industries in 2023.
That tally includes:
Climate activists have for years been calling on Canada to scale back its support of the fossil fuel industry and instead prioritize cleaner, renewable forms of energy.
"This is kind of the litmus test of whether the government is actually taking serious action," said Julia Levin, an associate director at Environmental Defence who prepared the report.
"It's failing that litmus test by continuing to give federal subsidies."
Environmental Defence's numbers are down only slightly from last year, when it calculated $20.2 billion in financial support — even though Environment Minister Steven Guilbeault eliminated "inefficient" fossil fuel subsidies in July.
Environment and Climate Change Canada did not immediately return a request for comment Wednesday.
The framework regarding inefficient subsidies was meant to phase out funding for oil and gas, with some exceptions, such as for projects that reduce greenhouse gas emissions, support clean energy or capture carbon and store it underground.
"We're eliminating subsidies to produce fossil fuels in Canada, unless those subsidies are aimed at decarbonizing the emissions of the sector," Guilbeault said at the time.
But the new rules do not apply to public financing, such as commercially viable loans, which the federal government does not consider a form of subsidy.
Regardless of what term is used, the government's financial backing gives the fossil fuel industry an advantage over energy alternatives, said Paasha Mahdavi, an assistant professor of political science at University of California, Santa Barbara, and an expert in oil subsidies.
Mahdavi, who was not involved in the report, said the findings illustrate "all these other tentacles through which financing and financial support can exist."
"You still have money from the government that's creating an uneven playing field," he said, citing the billions in loan guaranteed for Trans Mountain.
"That's still a pretty big deal, because that allows an oil company or a pipeline access to cheap capital, and that's right now one of the very important levers to pull to try to make decarbonization and energy transitions more successful."
Levin said the federal government makes it difficult to track and calculate the financing across departments.
"The government has not improved its transparency practices at all," she said.
"That means we are still required to do kind of a piecemeal analysis to the best of our ability because the government doesn't produce any kind of reporting on its own."
Laura Cameron, a policy advisor for the International Institute for Sustainable Development, said the report shows "there is still far too much public money being invested in fossil fuels."
"Continued support for this industry works directly against climate action and the energy transition," she said in a statement.
The analysis found that Export Development Canada provided public financing to many companies, often at subsidized rates. The financing included $300 million for Nova Chemicals Corporation, a petrochemical company, and $200 million for Enbridge.
The $1.3 billion for carbon capture projects in 2023 is set to increase in the years to come, under a new tax credit aimed at helping projects get off the ground. Proponents say it will help the oil and gas industry cut their emissions while maintaining production, while critics say the technology remains unproven at a large scale and the money could be better spent elsewhere.
The Parliamentary Budget Officer estimates the carbon capture, utilization and storage investment tax credit will cost $5.7 billion over five years.
The Canadian Association of Petroleum Producers (CAPP) says on its website that Canada's oil and gas producers "do not receive government production subsidies, nor is the industry requesting or expecting any such support."
Asked for more details on their position, CAPP spokesperson Jay Averill said in a statement that oil and natural gas production in Canada is "subject to royalties and taxes from every level of government, working to the benefit of Canadians right across the country."
"This differs from most other producing nations and is the exact opposite of a subsidy," Averill said.
Averill stressed the importance of the oil and gas sector to the economy. He said revenues from oil and gas reached $45 billion last year, and that capital investment from the industry is expected to reach about $40 billion.
Many international organizations, including the United Nations Development Programme, the International Energy Agency and the International Monetary Fund (IMF) have called for an end to fossil fuel subsidies.
Critics argue they undermine climate policies by distorting the market and delaying the transition to alternative technologies.
WATCH | Alberta oilsands facilities are emitting potentially harmful air pollutants:
According to the IMF, global subsidies surpassed $7 trillion US for the first time last year.
The assessment included what are called "implicit subsidies," which are the environmental costs of air pollution and climate damage from fossil fuels that producers and consumers aren't required to pay.
The IMF found that Canada doled out $2 billion in explicit fossil fuel subsidies; it calculated that the implicit cost was another $36 billion.
Environmental Defence is pressing Finance Minister Chrystia Freeland to include a tax on the windfall profits of the oil and gas industry in the 2024 budget, set to be tabled April 16.
"We should be taxing those windfall profits and returning that money to Canadians to meet their climate and affordability needs," Levin said.