Answer: A - P.M. Grootes, K.M. Cuffey, and J.M. Bolzan, among others.
Explanation: Dr. Anandakrishnan collaborated and coauthored with all of the people listed above and has worked with many other people.
During the year 1994, Dr. Sridhar Anandakrishnan collaborated with Kurt M Cuffey, Richard B Alley, Pieter M Grootes and John M Bolzan on the topic 'Calibration of the δ18O isotopic paleothermometer for central Greenland, using borehole temperatures'
They calibrated the δ 18O paleo-thermometer for central Greenland using borehole temperatures, a thermal model forced by a measured δ 18O record and a formal inverse technique. The calibration is determined mostly by temperature fluctuations of the last several centuries, including the Little Ice Age.
Results are generally insensitive to model variables, including initial condition, basal boundary condition, parameterization of snow thermal properties, ice thickness and likely errors in temperature and isotope measurements. Results of this borehole calibration also seem to be in agreement with modern spatial gradients of δ 18O and temperature.
They suggest that calibrations of isotopic paleothermometers using borehole temperatures are a useful paleoclimate tool because they are independent of spatial gradients and include the effects of prehistoric temperatures.
<h2>Answer: D. Rayleigh wave
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Rayleigh waves are a type of surface acoustic wave that causes particles on the surface of solids to travel along an elliptical path in the vertical plane that contains the direction of wave propagation.
These waves include longitudinal (P wave) and transverse (S wave) movements whose amplitude decreases exponentially as the distance from the surface increases.
This means Rayleigh waves are generated by the interference between the P and S waves on the surface of the Earth.
Deforestation, that would be clearing the land leading to desertification
You can easily google this.