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Atmospheric carbon dioxide (CO2) levels are currently at 418 parts per million (ppm), and by 2100 may exceed 900 ppm. The biological effects of lifetime exposure to CO2 at these levels is unknown. Previously we have shown that mouse lung function is altered by long‐term exposure to 890 ppm CO2. Here, we assess the broader systemic physiological responses to this exposure. Mice were exposed to either 460 or 890 ppm from preconception to 3 months of age, and assessed for effects on developmental, renal and osteological parameters. Locomotor, memory, learning and anxiety‐like behaviours of the mice were also assessed. Exposure to 890 ppm CO2 increased birthweight, decreased female body weight after weaning, and, as young adults, resulted in reduced engagement in memory/learning tasks, and hyperactivity in both sexes in comparison to controls. There were no clear anxiety, learning or memory changes. Renal and osteological parameters were minimally affected. Overall, this study shows that exposure of mice to 890 ppm CO2 from preconception to young adulthood alters growth and some behaviours, with limited evidence of compensatory changes in acid–base balance. These findings highlight the potential for a direct effect of increased atmospheric CO2 on mammalian health outcomes. Key points Long‐term exposure to elevated levels of atmospheric CO2 is an uncontrolled experiment already underway. This is the first known study to assess non‐respiratory physiological impacts of long‐term (conception to young adulthood) exposure of mice to CO2 at levels that may arise in the atmosphere due to global emissions. Exposure to elevated CO2, in comparison to control mice, altered growth patterns in early life and resulted in hyperactive behaviours in young adulthood. Renal and bone parameters, which are important to balance acid–base levels to compensate for increased CO2 exposure, remained relatively unaffected. This work adds to the body of evidence regarding the effects of carbon emissions on mammalian health and highlights a potential future burden of disease.

In this paper an image unmixing process is described which is based on the assumption that pixel reflectance is a linear mix of component reflectances. Three stages are used initially to calibrate the multispectral data to shaded reflectance: (I) minimum value subtraction, (2) band-mean standardization and (3) reflectance-mean equalization. Using laboratory or field spectra, linear mixing equations are then solved for substance proportions. For a geological test site in North Queensland, Australia, two vegetation types (green and dry) and four mineral types (clay, haematite, goethite and quartz) were unmixed using NSOOI aircraft scanner data. The six images created show the spatial abundance of individual vegetation and mineral types. The obscuring eITect of both green and dry vegetation was removed from mineral maps by separately scaling up mineral proportions in each pixel. Unmixed mineral maps were used to locate potentially economic hydrothermal alteration zones. In addition, scaled mineral proportions were used to recalculate brightness values for the original wavelength bands producing de-vegetated geological reflectance images which are useful for identification of rock· types.

D uring 1997 P apua N ew G uinea (P N G ) experienced an intense drought. Emergency famine relief operations provided many subsistence agricultural communities with food, water and health provisions during the height of the drought. The locations of relief operations were based on a rapid and spatially explicit extensive eld survey conducted at the height of the drought for all P N G . We have tested the utility of composite Advanced Very H igh Resolution Radiometer (AVH RR) data to assist in a rapid assessment of drought conditions in P N G . Composited data were used to provide a means to overcome the frequent cloudy conditions that exist in P N G . To assess the drought we divided land surface temperatures (T s ) by the N ormalized D iVerence Vegetation Index (N D VI ). The ratio (T s /N D VI ) increases during times of drought. This is due to the increase in T s associated with more net radiation being partitioned into the sensible heat ux and the decrease in N D VI associated with decreasing amounts of plant cover. A time series of T s /N D VI is a rapid indicator of the drought at the country and province level. We calculated the integral under the T s /N D VI curve for 1997, denoted Dec Jan T s /N D VI, which allowed us to validate the assessment in two ways. F irstly, it was compared with eld-based assessments of food supply (undertaken at the height of the drought ) which classi ed areas into ve grades. P lotting Dec Jan T s /N D VI against the percentage area of each of the 14 mainland provinces experiencing food supply problems (so lives were at risk) showed a strong positively correlated relationship (r2 0.818). Secondly, for seven meteorological stations plotting Dec Jan T s /N D VI against cumulative 1997 rainfall showed an inverse relationship (r2 0.809). Both forms of validation show that the composite AVH RR T s /N D VI ratio provides a rapid means to assess drought conditions in a cloudy environment such as P N G .

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