Hi. This is a question about the Ecological Footprint Model (EFM), just in case someone could give some insight. According to the EFM (Rees & Wackernagel, 1995), the average amount of productive land to satisfy the needs of each human being at the moment is about 2.3 global hectares. And the productive capacity on Earth is estimated about 1.9 global hectares per capita. Our global ecological demand, according to this, would be the equivalent to 120 percent of Earth's capacity to sustain us. In other words it would require 1.2 Earths. or one Earth for 1.2 years, to regenerate what is used in one year (These are data for year 2004). My problem to understand this unbalance is that if it was real it should already be detectable or measurable somehow. Somewhere there should already be a lack of resources. I'd appreciate any help to grasp the idea if you have some understanding of this model. I'm not interested in supporting or rejecting it, just in understanding how it describes the situation.