Updated 09/15/98
An MCR Example
To better illustrate the MCR technique, we offer an example using the Chukchi Shelf sample 85-69. The sample information:
# Sitename: Chukchi Shelf 85-69
# Location: Alaska, USA
# Latitude: 70.0 N (70.00)
# Longitude: 165.39 W (-165.65)
# Contact: Scott Elias
# Sample Name: 85-69
# Sample age: 11000 +\-60
# Lab Number: Beta-43953
Bembidion grapei
Helophorus splendidus
Holoboreaphilus nordenskioeldi
Tachinus brevipennis
Hydroporus polaris
Arpedium brachypterum
The first step in an MCR reconstruction is to establish the modern climatic tolerances for the individual species. Click on any of the above beetle names to see the climatic tolerance for that species (tolerance given as average July temperature and Avreage July T-Average January T).
The second step is to lay the climate envelopes on each other to find the area of climate overlap for that site. Once the area of overlap is defined, we can assign values for TMAX (July T) and TMIN (January T), which in this case are:
TMAX: 8°C to 12°C
TMIN: -25° to -33°C
These values must be calibrated, and using the calibration equations from Elias (1998), we get the following values for calibrated TMAX and TMIN:
TMAX: TMAX(Cal) = (10)*0.52 +6.13 = 11.33
TMIN: TMIN(Cal) = (-29)*0.72-6.4 = -27.28