摘要：Peroxide speciation and formaldehyde measurements have been made on ice cores retrieved from Law Dome, Antarctica. Measurements were made for ice deposited during four different periods: modern, pre-industrial Holocene, early Holocene and Last Glacial Maximum (LGM). The data show modern peroxide levels >50% above pre-industrial levels (at ∼1.6 μ mol L −1 ) and an absence of methyl hydroperoxide (down to a detection threshold of 0.003 μ mol L −1 ). Formaldehyde levels show a 40% increase from pre-industrial to modern times (rising from ∼0.07 μ mol L −1 to ∼0.10 μ mol L −1 ), with a further increase and possible seasonality near the surface which we associate with post-depositional processes. Peroxide levels in LGM ice are low, but formaldehyde concentrations are high (at ∼0.13 μ mol L −1 ) relative to modern levels. Similar high levels of formaldehyde are seen in early Holocene ice (∼6900 years BP).
