Does the biosphere lift nutrients against gravity, or redirect solar energy? A thermodynamic reframing of planetary biogeowork

Abstract. We use the term biogeowork for the thermodynamic work performed by the biosphere in shaping the Earth's energy and entropy budgets – whether supplied by metabolism or mediated through biological structures. Biological work at the Earth's surface is often imagined as mass transport against gravity – from whale pumps to plant transpiration – yet this framing conflates fundamentally different energy pathways. The biosphere shapes these budgets far beyond its own metabolic energy supply, yet biological energy supply and biologically mediated solar fluxes have not been clearly separated in a single quantitative framework. We propose a three-component decomposition of the biosphere's thermodynamic role: (i) active biogeowork, W_A, the mechanical work performed using metabolic free energy derived from gross primary production (GPP); (ii) mediated biogeowork, ΔΦ_M, the solar-driven flux redirected through biological structures – dominated by the biogenic enhancement of latent heat flux, ΔLE_bio, relative to an abiotic counterfactual land surface; and (iii) the resulting entropy-export enhancement, ΔṠ_bio. Using published global datasets, we estimate W_A ~ 10²⁰ J yr⁻¹ (≈2 % of GPP), ΔLE_bio ~ 5 × 10²³ J yr⁻¹ (≈30 % of global latent heat flux of 1.3 × 10²⁴ J yr⁻¹), and ΔṠ_bio ~ 2 × 10²⁰ J K⁻¹ yr⁻¹ (≈1–2 % of total planetary entropy production). The dimensionless leverage ratio Λ_bio ≡ ΔΦ_M / W_A ~ 5 × 10³ (range: 3–7 × 10³) quantifies the amplification by which biological infrastructure redirects solar energy per unit metabolic investment. The decomposition clarifies the distinct pathways through which the biosphere shapes the planetary energy budget, links biosphere degradation to planetary-scale thermodynamic consequences, and yields testable predictions connecting land-cover change, Bowen-ratio variability, and planetary-scale entropy export.