A pseudoproxy is a synthetic dataset used in

paleoclimatology Paleoclimatology ( British spelling, palaeoclimatology) is the scientific study of climates predating the invention of meteorological instruments, when no direct measurement data were available. As instrumental records only span a tiny part of ...

to test methods of reconstruction of global or hemispherical

climate change Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...

from

temperature record Global surface temperature (GST) is the average temperature of Earth's surface. More precisely, it is the weighted average of the temperatures over the ocean and land. The former is also called sea surface temperature and the latter is called ...

s, developed for reconstructing the

temperature record of the past 1000 years The temperature record of the last 2,000 years is reconstructed using data from climate proxy records in conjunction with the modern instrumental temperature record which only covers the last 170 years at a global scale. Large-scale reconstructi ...

using proxies for periods before the

instrumental temperature record Global surface temperature (GST) is the average temperature of Earth's surface. More precisely, it is the weighted average of the temperatures over the ocean and land. The former is also called sea surface temperature and the latter is calle ...

. In May 2002 Michael E. Mann and Scott Rutherford published a paper introducing this method of adding artificial noise to actual temperature records or to

climate model Numerical climate models (or climate system models) are mathematical models that can simulate the interactions of important drivers of climate. These drivers are the atmosphere, oceans, land surface and ice. Scientists use climate models to st ...

simulations to produce what they called "pseudoproxies". When the reconstruction

algorithm In mathematics and computer science, an algorithm () is a finite sequence of Rigour#Mathematics, mathematically rigorous instructions, typically used to solve a class of specific Computational problem, problems or to perform a computation. Algo ...

s were used with these pseudoproxies, the result was then compared with the original record or simulation to see how closely it had been reconstructed. They discussed the issue that regression methods of reconstruction tended to underestimate the amplitude of variation.;

References

*. *. Paleoclimatology {{paleoclimatology-stub