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• 1. [Article] Geothermics and climate change : 2. joint analysis of borehole temperature and meteorological data

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Geothermics and climate change : 2. joint analysis of borehole temperature and meteorological data Author: Chapman, David S., Harris, Robert N. copyrighted by American Geophysical Union Title: Geothermics and climate change : 2. joint analysis of borehole temperature and meteorological data Author: Chapman, David S., Harris, Robert N. copyrighted by American Geophysical Union Close

• 2. [Article] Repeat temperature measurements in boreholes from northwestern Utah link ground and air temperature changes at the decadal time scale

  Borehole temperature profiles provide a record of ground surface temperature (GST) change at the decadal to centennial time scale. GST histories reconstructed from boreholes are particularly useful in ...

  Citation × Citation Citation Abstract Copy Title: Repeat temperature measurements in boreholes from northwestern Utah link ground and air temperature changes at the decadal time scale Author: Chapman, David S., Harris, Robert N., Davis, Michael G. Borehole temperature profiles provide a record of ground surface temperature (GST) change at the decadal to centennial time scale. GST histories reconstructed from boreholes are particularly useful in climate reconstruction if changes in GST and surface air temperature (SAT) are effectively coupled at decadal and longer time periods and it can be shown that borehole temperatures respond faithfully to surface temperature changes. We test these assumptions using three boreholes in northwestern Utah that have been repeatedly logged for temperature over a time span of 29 years. We report 13 temperaturedepth logs at the Emigrant Pass Observatory borehole GC‐1, eight at borehole SI‐1 and five at borehole DM‐1, acquired between 1978 and 2007. Systematic subsurface temperature changes of up to 0.6°C are observed over this time span in the upper sections of the boreholes; below approximately 100 m any temperature transients are within observational noise. We difference the temperature logs to highlight subsurface transients and to remove any ambiguity resulting from steady state source of curvature. Synthetic temperature profiles computed from SAT data at nearby meteorological stations reproduce both the amplitude and pattern of the transient temperature observations, fitting the observations to within 0.03°C or better. This observational confirmation of the strong coupling between surface temperature change and borehole temperature transients lends further support to the use of borehole temperatures to complement SAT and multiproxy reconstructions of climate change. Title: Repeat temperature measurements in boreholes from northwestern Utah link ground and air temperature changes at the decadal time scale Author: Chapman, David S., Harris, Robert N., Davis, Michael G. Borehole temperature profiles provide a record of ground surface temperature (GST) change at the decadal to centennial time scale. GST histories reconstructed from boreholes are particularly useful in climate reconstruction if changes in GST and surface air temperature (SAT) are effectively coupled at decadal and longer time periods and it can be shown that borehole temperatures respond faithfully to surface temperature changes. We test these assumptions using three boreholes in northwestern Utah that have been repeatedly logged for temperature over a time span of 29 years. We report 13 temperaturedepth logs at the Emigrant Pass Observatory borehole GC‐1, eight at borehole SI‐1 and five at borehole DM‐1, acquired between 1978 and 2007. Systematic subsurface temperature changes of up to 0.6°C are observed over this time span in the upper sections of the boreholes; below approximately 100 m any temperature transients are within observational noise. We difference the temperature logs to highlight subsurface transients and to remove any ambiguity resulting from steady state source of curvature. Synthetic temperature profiles computed from SAT data at nearby meteorological stations reproduce both the amplitude and pattern of the transient temperature observations, fitting the observations to within 0.03°C or better. This observational confirmation of the strong coupling between surface temperature change and borehole temperature transients lends further support to the use of borehole temperatures to complement SAT and multiproxy reconstructions of climate change. Close

• 3. [Article] Long-term tracking of climate change by underground temperatures

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Long-term tracking of climate change by underground temperatures Author: Harris, Robert N., Ferguson, Grant, Beltrami, Hugo Copyrighted by American Geophysical Union. Title: Long-term tracking of climate change by underground temperatures Author: Harris, Robert N., Ferguson, Grant, Beltrami, Hugo Copyrighted by American Geophysical Union. Close

• 4. [Article] Mid-Latitude (30°–60° N) climatic warming inferred by combining borehole temperatures with surface air temperatures

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Mid-Latitude (30°–60° N) climatic warming inferred by combining borehole temperatures with surface air temperatures Author: Harris, Robert N., Chapman, David S. copyrighted by American Geophysical Union Title: Mid-Latitude (30°–60° N) climatic warming inferred by combining borehole temperatures with surface air temperatures Author: Harris, Robert N., Chapman, David S. copyrighted by American Geophysical Union Close

• 5. [Article] Climate change in India inferred from geothermal observations

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Climate change in India inferred from geothermal observations Author: Harris, Robert N., Rao, R. U. M., Roy, Sukanta, Chapman, David S. copyrighted by American Geophysical Union Title: Climate change in India inferred from geothermal observations Author: Harris, Robert N., Rao, R. U. M., Roy, Sukanta, Chapman, David S. copyrighted by American Geophysical Union Close

• 6. [Article] Repeat temperature measurements in borehole GC-1, northwestern Utah: towards isolating a climate-change signal borehole temperature profiles

  Copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Repeat temperature measurements in borehole GC-1, northwestern Utah: towards isolating a climate-change signal borehole temperature profiles Author: Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union Title: Repeat temperature measurements in borehole GC-1, northwestern Utah: towards isolating a climate-change signal borehole temperature profiles Author: Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union Close

• 7. [Article] Borehole temperatures and tree rings: Seasonality and estimates of extratropical Northern Hemispheric warming

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Borehole temperatures and tree rings: Seasonality and estimates of extratropical Northern Hemispheric warming Author: Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union. Title: Borehole temperatures and tree rings: Seasonality and estimates of extratropical Northern Hemispheric warming Author: Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union. Close

• 8. [Article] Snow and the ground temperature record of climate change

  Copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Snow and the ground temperature record of climate change Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union Title: Snow and the ground temperature record of climate change Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union Close

• 9. [Article] Climate change on the Colorado Plateau of eastern Utah inferred from borehole temperatures

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Climate change on the Colorado Plateau of eastern Utah inferred from borehole temperatures Author: Chapman, David S., Harris, Robert N. copyrighted by American Geophysical Union Title: Climate change on the Colorado Plateau of eastern Utah inferred from borehole temperatures Author: Chapman, David S., Harris, Robert N. copyrighted by American Geophysical Union Close

• 10. [Article] A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah

  Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these ...

  Citation × Citation Citation Abstract Copy Title: A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these two quantities. The influence of surface air temperature (SAT), incident solar radiation, and snow cover on surface ground temperature (SGT) variations are explored. SAT variations explain 94% of the variance in SGT. Incident solar radiation is the primary variable governing the remaining variance misfit and is significantly more important during summer months than winter months. A linear relationship between the ground–air temperature difference (ΔT[subscript]sgt-sat) and solar radiation exists with a trend of 1.21 K/(100 W m⁻²); solar radiation accounts for 1.3% of the variance in SGT. The effects of incident solar radiation also account for the 2.47-K average offset in ΔT[subscript]sgt-sat. During the winter, snow cover plays a role in governing SGT variability, but exerts only a minor influence on the annual tracking of ground and air temperatures at the site, accounting for 0.5% of the variance in SGT. These observations of the tracking of SGT and SAT confirm that borehole temperature changes mimic changes in SAT at frequencies appropriate for climatic reconstructions. Title: A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these two quantities. The influence of surface air temperature (SAT), incident solar radiation, and snow cover on surface ground temperature (SGT) variations are explored. SAT variations explain 94% of the variance in SGT. Incident solar radiation is the primary variable governing the remaining variance misfit and is significantly more important during summer months than winter months. A linear relationship between the ground–air temperature difference (ΔT[subscript]sgt-sat) and solar radiation exists with a trend of 1.21 K/(100 W m⁻²); solar radiation accounts for 1.3% of the variance in SGT. The effects of incident solar radiation also account for the 2.47-K average offset in ΔT[subscript]sgt-sat. During the winter, snow cover plays a role in governing SGT variability, but exerts only a minor influence on the annual tracking of ground and air temperatures at the site, accounting for 0.5% of the variance in SGT. These observations of the tracking of SGT and SAT confirm that borehole temperature changes mimic changes in SAT at frequencies appropriate for climatic reconstructions. Close