Al_U_Card, on 2018-November-30, 20:54, said:
Typical alarmist cherry pie
Since Nige1 asked nicely, I'll analyze this particular post because it represents easily understandable data.
First, why is this posted?
Presumably because there has been stories in the media that global warming made the recent California fires some of the worst in California history. I guess Al_U_Card didn't have an extra minute to write something to that effect, or to link to some article.
What is the significance of the charts?
Apparently Al_U_Card thinks just posting this is enough to refute any global warming impact on California fires because a climate change denier noticed that burned acreage drastically decreased in the last 100 years without giving a second thought about the actual data.
Since I have a degree in biostatistics, I've got a lot of experience in analyzing various types of data.
The first thing I noticed is that between about 1932 and 1984, the amount of acreage burned decreased from about 53 million acres to a little over 1 million acres. Wow, a 98% decrease in acreage. The deniers must have passed out from joy at this chart
There's a TV show in the US called "What on Earth?" on the Science channel. Usually the show uses satellite photos that show something unusual and ask what's going on. There's a panel of scientists that then give various hypotheses to explain what is shown in the photo. Some can be pretty far fetched, others may be more probable. If possible, there's usually an on the ground investigation to see what's actually going on, but sometimes there is no definitive conclusion.
I'll give a What on Earth? type analysis:
Maybe there was a worldwide nuclear war or a near extinction level meteor strike that caused a nuclear winter that decreased temperatures so much that forest fires were nearly eliminated going on until today. I googled worldwide nuclear war, and extinction level meteor strike and came up empty.
I also looked out my window the other day and saw clear blue skies, so I'm going to have to eliminate this theory.
Along similar lines, it could have been massive volcanic eruptions like the Deccan Traps that spewed particulates into the air that blocked the sun and caused temperatures to massively drop worldwide for decades. Again, google came up empty.
Maybe we are at the start of a new ice age and the global ice sheet is rapidly headed down from the Arctic down to lower latitudes. Hmmm, ski areas in my area have been opening up later and later in the year, so I'm not even going to google whether we are beginning a new ice age. If somebody has some spare time, they can investigate and post breaking news.
Maybe all the forests got burned down by previous year's forest fires so there's nothing left to burn? Hmmm, there could be something to that, but a 98% reduction in 50 years? And forests have been regrowing after forest fires for millions of years. You would think somebody would have noticed that.
Deforestation and industrialization. Yep, that's definitely happening. New cities and ever expanding suburbs, industrial plants, highways and roads and all sorts of development. So that accounts for some amount in the decrease of burned acreage, but 98%? I don't think so.
Edit: Another point to take into account is firefighting in public lands.
U.S. FOREST SERVICE FIRE SUPPRESSION
Clearly this has a noticeable effect on the acreage burned. And since the early 1900's, we've gone from firefighters with axes and shovels (still have them), to supplementing them with airplanes and helicopters that drop water, foam and fire retardants from the air to increase the effectiveness of the firefighting.
With deforestation reducing the amount of wilderness areas, and more effective fire fighting capabilities, one might predict, all things being equal, that the burned acreage should be reducing every year.
Also, between about 1953 and 1957, about 4 years time, the burned acreage decreased from about 13 million acres to about 3 million acres, and the acreage has never been as high as 10 million since 1957.
Conclusion:
My educated guess is that something drastically changed in the reporting methods between 1953 and 1957 (and it looks like this happened from 1928 as well) so you can't compare recent years with early and mid 20th century numbers.
In fact, these numbers look like the were taken from this site:
National Interagency Fire Center
which has this specific warning:
Quote
The National Interagency Coordination Center at NIFC compiles annual wildland fire statistics for federal and state agencies. This information is provided through Situation Reports, which have been in use for several decades. Prior to 1983, sources of these figures are not known, or cannot be confirmed, and were not derived from the current situation reporting process. As a result the figures prior to 1983 should not be compared to later data.
So there you have it. Al_U_Card posted a chart which he assumes shows that current forest fires have no correlation to global warming and in fact probably shows that temperatures must be decreasing if there is any correlation at all.
If that's not "Yada" then you haven't seen "Yada"