Ecological forecasting uses knowledge of physics, ecology and physiology to predict how ecological populations, communities, or ecosystems will change in the future in response to environmental factors such as climate change. The ultimate goal of the approach is to provide people such as resource managers and designers of marine reserves with information that they can then use to respond, in advance, to future changes, a form of adaptation to global warming. One of the most important environmental factors for organisms today is global warming. Most physiological processes are affected by temperature, and so even small changes in weather and climate can lead to large changes in the growth, reproduction and survival of animals and plants. The scientific consensus is that the increase in atmospheric greenhouse gases due to human activity caused most of the warming observed since the start of the industrial era. These changes are in turn affecting human and natural ecosystems. One major challenge is to predict where, when and with what magnitude changes are likely to occur so that we can mitigate or at least prepare for them. Ecological forecasting applies existing knowledge of how animals and plants interact with their physical environment to ask how changes in environmental factors might result in changes to the ecosystems as a whole. One of the most complete sources on the topic is the book Ecological Forecasting written by Michael C. Dietze.
Approaches
Ecological forecasting varies in spatial and temporal extent, as well as in what is being forecast.
Population models may be used to generate short-term abundance forecasts using knowledge of population dynamics and recent environmental conditions. These models are used especially in fisheries and disease forecasting.
* Correlative SDMs, also known as climate envelope models, rely on statistical correlations between existing species distributions and environmental variables to outline a range of environmental conditions within which a species can exist. New range boundaries can then be forecast using future levels of environmental factors such as temperature, rainfall, and salinity from climate model projections. These methods are good for examining large numbers of species, but are likely not a good means of predicting effects at fine scales.
* Mechanistic SDMs use information about a species' physiological tolerances and constraints, as well as models of organismal body temperature and other biophysical properties, to define the range of environmental conditions within which a species can exist. These tolerances are mapped onto current and projected environmental conditions in the landscape to outline current and forecasted ranges for the species. In contrast to "climate envelope" approaches, mechanistic SDMs model the fundamental niche directly, and are therefore much more exact. However, the approach requires more information is also usually more time-consuming.
Other types of models may be used to forecast biodiversity over evolutionary time scales. Palaeobiology modeling uses fossil and phylogenetic evidence of biodiversity in the past to project the trajectory of biodiversity in the future. Simple plots can be constructed and then adjusted based on the varying quality of the fossil record.
Forecasting examples
Biodiversity
Using fossil evidence, studies have shown that vertebrate biodiversity has grown exponentially through Earth's history and that biodiversity is entwined with the diversity of Earth's habitats.
Temperature
Forecasts of temperature, shown in the diagram at the right as colored dots, along the North Island of New Zealand in the austral summer of 2007. As per the temperature scale shown at the bottom, intertidal temperatures were forecast to exceed 30 °C at some locations on February 19; surveys later showed that these sites corresponded to large die-offs in burrowing sea urchins.
