Comments by "Old Scientist" (@OldScientist) on "CBC News" channel.

  1. 19
  2. Weather events are not climate. The severity of individual weather events cannot be attributed to factors implicated in man-made climate change. Global burned area has decreased by one quarter this century! For the whole of Canada, there is no trend in burn acreage for the period 1980-2021. The previous highest burn acreage was in 1989. Over that same period the trend for number of fires was slightly downwards (CNFDB). Note that 2020 had the lowest recorded burn acreage and number of fires, so can that record be attributed to man-made climate change? Burn acreage was much, much, higher in the US during the 1920's, 30's and 40's. It peaked in 1930 at well over 50,000,000 acres. The trend is downwards (1926-2020 NIFC US) eventhough CO2 has increased exponentially. For 2000 onwards the average burn acreage is much less than 10,000,000 acres. The number of fires has also declined. Remember CO2 was increasing all the time. Data for Siberia seems harder to come by. However, for the period 1997-2016, the trend was highly variable (by a factor of 4) but the trend for the annual burn acreage was downwards (Global Fire Data). For the Amazon (2003-2019), 2010 was the record year for fire emissions with all subsequent years lower by at least ½. When it comes to wildfires there is nothing unusual about this summer's fire season in Europe (look it up on the EFFIS website). Besides all this the forest fire record in Southern Europe is related to the previous winter rains, not summer temperatures. Wetter winters encourage more plant grow, which forms more fuel for fires when it dries out. Mediterranean summers are always hot and dry enough to allow fires to spread. Furthermore, with regard to the IPCC, they have not detected or attributed the number of fires or the burn acreage to man-made climate change. Also IPCC only has medium confidence ( that's a 50-50, so toss a coin) that weather conditions that promote wildfires (fire weather) have become more probable in southern Europe, northern Eurasia, the USA, and Australia over the last century. Note that annual Global Wildfire Carbon Emissions have been declining dramatically since 2003, with 2022 being the lowest on record (Copernicus). "With higher CO2, increased tree cover leads to reduced fire ignition and burned area, and provides a positive feedback to tree cover" (Chen et al, 2019), so burning fossil fuels actually leads to less forest fire! Global burned area has decreased by nearly by 24.2% in 20 years (Chen et al, 2023). There is no climate crisis...there isn't even any evidence for it.
    10
  3. 5
  4. 4
  5. 3
  6. 3
  7. 2
  8. 2
  9. 2
  10. @RP S  I wasn't bringing up irrelevant regional temperature changes from the Medieval Warm Period. The Medieval Warm Period was global in extent as demonstrated by research done on every continent and was focused around 1000AD. This extensive research taken together shows that the Medieval Warm Period was both qualitatively and quantitatively warmer than the present. As regards the rate of temperature change for the current modern era, it has been neither consistent nor rapid both temporally and spatially. The climate of the US in the 20th century is good example of this. The US has by far the best actual temperature recordings for this period with very little coverage elsewhere outside of Europe. Data from NOAA (2021) shows uneven warming focused on the South East through until it peaks in the 1930s. Where it should be noted the highest average maxima temperature records remain to this day. Some areas of the West showed negligible warming. There then followed a general continent-wide cooling into the 1970s. Then the West began to warm, but the South East continued to cool, so that by the end of the century some SE areas were cooler than they had been a century before. This pattern of uneven warming continues up to the present day. All of this demonstrates to my mind that the climate has a strong internal variability without the requirement for any external anthropogenic forcing. Globally satellite data shows how variable the Earth's climate is with changes up or down of more than 1°C occurring from one year to the next. When it comes to comparing the rates of change, as I pointed out previously, the CET and Dansgaard–Oeschger events show much more rapid changes than current observations. When it comes to the extent of the previous warming events, they were not local in nature. The Minoan Warm Period was identified in the Greenland Ice record as well as the Mediterranean. The Roman Warm Period was not just in Rome (see Wang et, 2012, published in Quaternary International) but has also been identified on the other side of the world. Around 1700AD the Little Ice which again was a global event reached its nadir with temperatures possibly 2°C lower than present. Warming proceeded hesitantly from that point (so before the onset of the Industrial Revolution and all the nasty CO2). With initial rapid warming then a cooling in the earlier 1800s, followed by rapid warming again in the early part of the 20th century where the average daily maxima records were set (1930s) and remain extant to this day. There followed a general cooling in the mid-century which lasted until that latter 1970s. Since that point there has been a hesitant warming of 0.13°C per decade. My précis of the Current Warm Period is a little simplistic for brevity but it has been neither consistent nor rapid both temporally and spatially. Projecting forward shows a global temperature increase of 1°C by 2100. This is survivable. Indeed the rise in temperature will encourage the flourishing of humanity and life in general as in previous periods of warming.
    2
  11. 2
  12. 1
  13. 1
  14. 1
  15. @RP S  The has been warming at an averaged rate of 0.13°C per decade (UAH v6) since 1979 not 0.2°C. It was warmer during the Medieval (Elbert, 2013, 2.9°C above present), Roman (Margaritelli, 2020, 2°C above present), and Minoan Warm Periods (Lécuyer, 2018, 4°C above present). It was certainly warmer during the Holocene Climatic Optimum, so during our current interglacial. If you want a citation, try Quaternary Research Volume 53, Issue 3, May 2000, Pages 302-311. This makes the point that it was upto 7°C warmer on the shores of the Arctic during that time, with trees growing on the shores of the ocean (which would have been ice free in the summer), far to the north of the current treeline. The northern coast of Greenland was, during parts of the Pleistocene, warmer by double figures than today. The summer and winter average minimum temperatures of 10 degrees Celsius and 17 degrees C, respectively, were more than 10 degrees C warmer than present day. I think it was a maximum of 19 °C warmer than today. Remarkable. Maybe it was those pesky Neanderthals driving around in their SUVs. That one's been all over the news but if you want a citation I think it was in the 7th December 2022 issue of Nature. The original research was done by some Danish chappy. If you want some really rapid warming look at the CET (Central England Temperature) Instrumental Record between 1690 and 1730 (3°C increase). That might not be reliable enough for you though. Why not try the Dansgaard–Oeschger events? The Dansgaard–Oeschger events were global (Dima et al, 2018).About 11,500 years ago, averaged annual temperatures on the Greenland ice sheet increased by around 8 °C over 40 years, in three steps of five years, but a 5 °C change over 30–40 years is more common for these events. Some researchers believe the Medieval Warm Period was one of these, but I'm not convinced. However, I can provide upwards of 100 citations of science papers that together show the Medieval Warm Period was qualitatively and quantitatively warmer than the current warming, and that it was global in nature, focused around the year 1000. The current warming began around 1700 prior to any large scale combustion of fossil fuels. Also the warming has been small (1°C) and appears to have been largely beneficial. It has not been smooth, for example there was a period of cooling during the 50s, 60s and 70s (NOAA). When many scientists believed the next ice age had begun. Current warming is smaller than predicted by nearly all models (as I said 0.13°C per decade since 1979, UAH v6). This could result in a further 1° of warming by 2100 which can be adapted to, as with the previous 1°.
    1
  16. 1
  17. 1