Palmer et al., 1998 (Ocean pH-depth profiles)

Question 1

Measurement of … isotope compositions in species of planktonic … (a type of protist) that calcified their … at different depths in the water column were used to reconstruct the … profile of the upper water column in the tropical ocean in an area of the ….

Answer 1

boron, foraminifera, tests, pH, Pacific

Question 2

Results for … time windows from the middle … to the late … indicate pH-depth profiles similar to that of the modern ocean ocean in this area. This method may greatly aid in our understanding of the global … ….

Answer 2

five, Miocene, Pleistocene, carbon cycle

Question 3

The pH of seawater plays an important role in determining the …-… … budget

Answer 3

ocean-atmosphere carbon

Question 4

The relative proportions of different boron … and compounds are largely a function of …. Foraminifera uptake boron compounds so their fossils can be used to estimate the pH changes in … with time and subsequently even … … levels

Answer 4

isotopes, pH, seawater, atmospheric CO2

Question 5

This study, instead of simply determine variations in the pH of … water, tested whether foraminifera species record the … … of seawater pH.

Answer 5

depth profile

Question 6

The pH gradient of the upper ocean depends on the carbonate chemistry of seawater, which largely reflects … … rates

Answer 6

primary productivity

Question 7

The study assumed that water column …-… profile was constant

Answer 7

temperature-depth

Question 8

pHs were calculated and compared with the pH-depth profile directly measured on seawater from this area of the Pacific.

Answer 8

This is true

Question 9

All five samples record surface seawater pH values within the range observed in the oceans …, and they all show a … in the calculated pH with depth that is similar to that observed in the present-day equatorial pacific

Answer 9

today, decrease

Question 10

Foraminifera were picked as they…

Answer 10

don’t alter the fractions of boron isotopes when they use it to help calcify their tests, or alter it very little