As muitas limitações dos modelos climáticos

Mesmo a escola da climatologia que vive à custa dos modelos climáticos reconhece limitações à sua aplicação como se refere a United States Environmental Protection Agengy (EPA) no site «http://www.epa.gov/globalwarming/uncertainties.html».

Esta Agência da administração pública norte-americana – equivalente ao Instituto do Ambiente – divide as “certezas– incertezas” em três categorias: - 1) “What’s known for certain ?” (zona clara); 2) “What’s likely but not certain” ? (zona cinzenta) e 3) “What are the big unknowns ?” (zona escura).

Interessa averiguar o que cai totalmente neste zona escura da qual a EPA afirma:

«What are the Big Unknowns?

Scientists have identified that our health, agriculture, water resources, forests, wildlife and coastal areas are vulnerable to the changes that global warming may bring. But projecting what the exact impacts will be over the 21st century remains very difficult. This is especially true when one asks how a local region will be affected. Scientists are more confident about their projections for large-scale areas (e.g., global temperature and precipitation change, average sea level rise) and less confident about the ones for small-scale areas (e.g., local temperature and precipitation changes, altered weather patterns, soil moisture changes). This is largely because the computer models used to forecast global climate change are still ill-equipped to simulate how things may change at smaller scales. [See the U.S. Climate section for more detail on climate models.]
Some of the largest uncertainties are associated with events that pose the greatest risk to human societies. IPCC cautions, "Complex systems, such as the climate system, can respond in non-linear ways and produce surprises. " There is the possibility that a warmer world could lead to more frequent and intense storms, including hurricanes. Preliminary evidence suggests that, once hurricanes do form, they will be stronger if the oceans are warmer due to global warming. However, the jury is still out whether or not hurricanes and other storms will become more frequent.More and more attention is being aimed at the possible link between El Niño events – the periodic warming of the equatorial Pacific Ocean – and global warming. Scientists are concerned that the accumulation of greenhouse gases could inject enough heat into Pacific waters such that El Niño events become more frequent and fierce. Here too, research has not advanced far enough to provide conclusive statements about how global warming will affect El Niño.

Living with Uncertainty

Like many pioneer fields of research, the current state of global warming science can't always provide definitive answers to our questions. There is certainty that human activities are rapidly adding greenhouse gases to the atmosphere, and that these gases tend to warm our planet. This is the basis for concern about global warming.The fundamental scientific uncertainties are these: How much more warming will occur? How fast will this warming occur? And what are the potential adverse and beneficial effects? These uncertainties will be with us for some time, perhaps decades.Global warming poses real risks. The exact nature of these risks remains uncertain. Ultimately, this is why we have to use our best judgement – guided by the current state of science – to determine what the most appropriate response to global warming should be.»

Interessa registar a preocupação do uso verbal tal como may, could, will be... if, should.