= Solution
The estimate assumes the entire $2\,\mathrm{m^2}$ surface remains exposed at $35\,{}^\circ\mathrm C$ continuously. Clothing reduces direct exposure and presents a cooler outer emitting surface; the skin <temperature> also varies across the body and decreases in cooler surroundings through changes in blood flow. Body posture and nearby surfaces reduce the effective exchange <area>, while blankets and warm surrounding surfaces reduce net <radiative heat transfer>. These effects make the full-area, constant-<temperature> daily radiative estimate too large for ordinary clothed conditions.
The unit <emissivity> approximation is already fairly good for skin in the thermal <infrared>, so reducing <emissivity> alone is not the main correction. Also, <convection>, <thermal conduction>, and evaporation are additional channels of <heat transfer>; their existence does not subtract from the calculated radiative term. The computed number is a simplified \b[radiative] loss, not a complete metabolic <energy> budget.
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