‘We are just recovering from the LIA’–Why should we expect this to happen?
(Part of the How to Talk to a Global Warming Skeptic guide)
Objection: Today’s warming is just a recovery from the Little Ice Age.
Answer: This argument relies on an implicit assumption that there is a particular climatic baseline to which the earth inexorably returns — and thus that a period of globally lower temperatures will inevitably be followed by a rise in temperatures. What is the scientific basis for that assumption?
There is no evidence of such a baseline. The climate is influenced by many factors, which change or remain stable in their own ways. The current understanding of the Little Ice Age is that it was likely the result of a decrease in solar irradiance combined with an increase in volcanic activity, blocking additional sunlight. The LIA was also not particularly well synchronized globally, affecting different regions at different times. Scientists are aware of no century-scale pattern in solar output or volcanic activity, so there’s no reason to expect a reversal of those changes. As it happens, solar output did increase somewhat in the early 20th century, which did contribute to warming at that time. However, that’s not behind current warming.
Another problem with appealing to a natural recovery from the LIA is that temperature has now risen to levels higher than the assumed baseline climate. So even if some recovery were to be expected, why have we now exceeded it? This argument has problems similar to the more general “it is part of a natural cycle” argument.
More stories in this series:
(Part of the How to Talk to a Climate Skeptic guide) Objection: Despite what the computer models tell us, there is actually no evidence of significant global warming. Answer: Global warming is not an output of computer models; it is …
(Part of the How to Talk to a Global Warming Skeptic guide) Objection: CO2 levels are recorded on top of Mauna Loa … a volcano! No wonder the levels are so high. (image courtesty of Global Warming Art)
(Part of the How to Talk to a Global Warming Skeptic guide) Objection: The apparent rise of global average temperatures is actually an illusion due to the urbanization of land around weather stations, the Urban Heat Island effect.
(Part of the How to Talk to a Global Warming Skeptic guide) Objection: One hundred and some years of global surface temperatures is not long enough to draw any conclusions from or worry about anyway. Answer: The reliable instrumental record …
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