Sources of information and numbers used in: Defusing BC's big, bad carbon bomb
(1) "The average stumpage rate in BC—the price the Province charges forestry companies for harvesting a cubic metre of tree on Crown land—was around $23 for both the interior and the coast in 2019."
We used the Ministry of Forests (MoF) Harvest Billing System to determine the total volume cut and total stumpage assessed for both the interior and the coast.
(2) "raw logs for export were selling at an average price of $128 per cubic metre through 2019"
We averaged the MoF's published values for log market prices per cubic metre to arrive at this figure.
(3) "Raw logs worth $4.146 billion were exported from BC to other countries for processing over the past five years."
To estimate this value, we used the MoF's records of "Weekly Advertising Lists" to establish the volume for which permits were sought to export raw logs for each of the past 5 years, and the annual average market value for logs on the coast published by the MoF. No information is published by the MoF on what portion, if any, of the volume on the Weekly Advertising Lists is not exported. We make the assumption that it was all exported. The Province ought to provide additional information.
(4) "This huge overcut—unnecessary to meet domestic and international demand for BC’s finished wood products—has averaged 6.5 million cubic metres per year over those five years, equal to 41 percent of the total cut on Crown and private land on the coast."
The average 6.5 million cubic metres was determined by totalling the volumes advertised in the "Weekly Advertising Lists" for 2015 to 2019. The "41 percent" was estimated by comparing MoF values for volume cut on "all land" on the coast with the total volume from the "Weekly Advertising Lists" for each year. Some volume of raw logs that are exported each year is from the interior of BC. But the total volume, regardless of origin, is "equal to 41 percent" of the coastal cut. Here are the export volumes advertised by year and the percentage of the total coastal cut:
2015: 6.9 million cubic metres, 41 percent
2016: 8.1 million cubic metres, 46 percent
2017: 6.7 million cubic metres, 43 percent
2018: 5.03 million cubic metres, 31 percent
2019: 5.6 million cubic metres, 43 percent
(5) "Our provincial forest’s capacity to serve as a carbon sink has vanished. Its catastrophic collapse is recorded in a 20-year segment of the Province’s annual inventory of provincial greenhouse gas emissions. In 1997, BC forests could sequester the equivalent of 103 megatonnes of CO2 annually. By 2017 that had fallen to 19.6 megatonnes."
Here's the relevant section from the Province's 2017 GHG Emissions Inventory (click to enlarge). The yellow horizontal band highlights the above reference.
(6) Environment Canada estimated upstream emissions from oil-sands-related operations in 2017 were 80.5 megatonnes. This estimate is on page 20 of the attached document: national-GHG-emissions-en.pdf1.09 MB · 30 downloads
(7) "Each cubic metre of wood will eventually produce about 0.82 tonnes of CO2-equivalent emissions."
This was determined by using the following parameters:
• About one-half (.5) the dry weight of a tree is carbon.
• The decay of one tonne of tree carbon will result in the release of 3.667 tonnes of carbon-dioxide-equivalent emissions
• The average density of timber felled in 2018 on the Coast (based on MoF numbers for relative volumes of tree species cut, and their known dry-weight densities) was about .447 tonnes/cubic metre
So, carbon-dioxide-equivalent emissions released by decay of one tonne of average coastal wood = 1/2 x 3.667 x .447 = .82 tonnes/cubic metre.
(8) “For 2017 it noted that 'Emissions from Decomposition of Harvested Wood Products' contributed 42 megatonnes annually to the provincial greenhouse gas inventory, which is close to our estimate of 44 megatonnes for 2018”.
This is from the same source as in (5) above. See the bottom right corner of the spreadsheet (highlighted in yellow, above).
(9) "There were 17,800 people employed in “forestry and logging with support activities” in all of BC in 2018, according to BC Stats."
From a spreadsheet found here: https://www2.gov.bc.ca/gov/content/data/statistics/employment-labour/labour-market-statistics
The relevant section is reproduced below (click to enlarge):