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The report reaches ambiguous conclusions on two major Canadian environmental events, the 2013 southern Alberta flood and the 2016 Fort McMurray wildfire.

On the flood, the report states that while greenhouse gases increased the likelihood of extreme, flood-producing rainfall, “confidence in this attribution is low because of the difficulties in modelling precipitation extremes, which exhibit large variability at small scales, such as for this event.”

The report claimed “medium confidence” that climate change increased the wildfire risk associated with the Fort McMurray event. “The assessment of medium confidence balances high confidence in human influence on the increase in temperature, which affects fire risk strongly, with many other factors contributing to this event that are more difficult to represent in a climate model.”

The report turns sensational when it looks to the future, mostly based on a selection of climate models and projections that are beyond the ken of most humans, including some scientists. A good example is the projections of rising sea level to the year 2100.

Among the problems is the fact that in parts of Canada the land is rising, and in other parts it’s sinking. Around Hudson Bay, the “relative sea level” is falling because the “rate of uplift” in the land is increasing due to geological movements. In Atlantic Canada, where land masses are falling, the sea-level rise appears greater. The sea level at Halifax, where the land is falling, has been rising for more than a century.

As with much of climate science, there are reasons to doubt the worst predictions, especially about rising sea levels. While the media jumped aboard Environment Canada’s sea-level projections, the science remains highly speculative, some say improbable. In a paper last year, U.S. climate scientist Judith Curry warned “ extreme values of possible sea level rise are regarded as extremely unlikely or so unlikely that we cannot even assign a probability.”

And so it goes with climate science reports, where the worst extremes are routinely trotted out as the new normal.