Ice layer dating
For instance, in the oxygen isotope method, uniformitarian scientists normally need eight measurements per annual cycle to pick up the “annual” signature.As an example, halfway down the GRIP Greenland ice core at about one mile (1,600 m) deep, uniformitarian scientists believe the annual layer thickness is 4 inches (10 cm).3 The measurements for oxygen isotopes would then be spaced every 1/2 inch (1 cm) apart.Some scientists believe that if the ice somehow disappeared, it probably would not return in the present climate. Many ice cores have been drilled deep into both the Antarctica and Greenland ice sheets since the 1960s (see figures 12.1 and 12.2).It is observed today that these ice sheets incorporate dust, acids, pollution, etc. Near the top of the ice sheets, annual layers can be distinguished by measuring the many variables related to the seasons.The claimed 110,000 annual layers in the GISP2 ice core to near the bottom of the Greenland ice sheet is not a straightforward deduction.The annual layers, indeed, show up well near the top of the ice sheet.Since the creationist model postulates an annual layer thickness significantly thicker, say 12 inches (30 cm) as an example, the uniformitarians have taken more measurements than needed and are, therefore, measuring multiple cycles of oxygen isotopes within one year.
Because of extreme annual layer thinning at the bottom of the core in the uniformitarian model compared to the creationist model, the uniformitarian scientists may be counting 100 layers that they think are annual.
The assumed thickness of the annual layers is important because it constrains the annual thickness in the measurements.
The measurements can deviate a little from the assumed annual layer thickness but not by much.
For the visible strata (and, we believe, for any other annual indicator at accumulation rates representative of central Greenland), it is almost certain that variability exists at the subseasonal or storm level, at the annual level, and for various longer periodicities (2-year, sunspot, etc.).
We certainly must entertain the possibility of misidentifying the deposit of a large storm or a snow dune as an entire year or missing a weak indication of a summer and thus picking a 2-year interval as 1 year.The method of counting annual layers only works with the high accumulation Greenland ice sheet.