Your argument fails on both arithmetic and methodology.

First, your maths is wrong.

28 million × 1 kg/day × 365 × 300 m²/kg = 3.066 million km², not 8.4 million.

Even using your graph's exact 326.21 m²/kg, it's 3.334 million km².

At 500 g/day of animal food, including edible fat and organs, that becomes 1.667 million km², roughly 22% of Australia.

And you're applying a global beef-herd average as though it measures Australian grazing capacity or represents all animal foods. It does neither.[^1]

Second, your own research exposes the flaw in your land-use argument.

Its modeled removal of beef-herd beef and mutton frees 1.92 billion hectares globally, of which 1.85 billion (96%) are pasture. Arable land decreases by only 70 million hectares (~6%).[^2][^3]

Pasture isn't cropland. Roughly two-thirds of global grazing grassland cannot be converted to cropland.[^3][^4] Ruminants produce human food from vegetation growing on land unsuitable for cultivation.

Third, ruminants can outperform crops when land suitability is considered.

A direct comparison found that dairy cattle on marginal peat soils produced 1 kg of human-digestible protein where crops could produce only 0.67 kg on the same land.[^5]

Globally, 86% of livestock feed is human-inedible, and only ~5% of ruminant feed consists of potentially food-competing grains and soybean meal.[^4][^6]

Australian beef systems achieved quality-adjusted human-edible protein output/input ratios of 1.96 (grain-finished) and 1,597 (grass-fed), the latter reflecting negligible human-edible feed inputs.[^7]

That's converting resources humans cannot directly consume into high-quality nutrition.

Fourth, count the whole animal.

An Australian lamb study found edible co-products contributed 24% of edible weight, 37% of fat and 42% of iron.[^8]

Ignoring edible fat and organs understates nutritional output. Kilograms of meat alone don't capture total food value.

Finally, biogenic methane isn't fossil CO₂.

Cattle recycle atmospheric carbon captured through photosynthesis. Methane has an atmospheric lifetime of approximately a decade.

Stable methane emissions sustain approximately stable methane-driven warming, unlike continuing fossil CO₂ emissions, whose warming effects accumulate. GWP* accounts for this fundamental difference.[^9][^10]

Your 8.4-million-km² calculation is wrong. Your broader argument confuses global land-use averages with Australian carrying capacity, pasture with cropland, raw food weight with nutritional efficiency, and biogenic methane with fossil carbon.

Your conclusion doesn't follow from your evidence.

[^1]: Poore & Nemecek data — Our World in Data [^2]: Poore & Nemecek (2018) — Corrected Supplementary Materials, p. 63 [^3]: ALEPH2020 — Land Use and Biodiversity [^4]: Mottet et al. (2017) [^5]: Van Zanten et al. (2016) — Land Use Efficiency [^6]: ALEPH2020 — Feed-Food Competition [^7]: Thomas et al. (2021) [^8]: Wingett & Alders (2023) [^9]: ALEPH2020 — Greenhouse Gas Emissions [^10]: Lynch et al. (2020) — GWP*