What are some other electrical performance criteria for grounding electrodes?
Besides Resistance-to-Ground, other factors to determine in selecting electrodes include, ampacity (the ability to handle current or amps), corrosion resistance, life expectancy, resistance-to-temperature change, and of course resistance over time. Seasonal changes in temperature can cause very dramatic differences in the resistivity of the soil, thus impacting the resistance-to-ground of the grounding system. This is especially true in areas where permafrost exists (permafrost is a soil condition that exists in the extreme northern and southern climates where the top soil is always frozen).
