Published: July 10, 2019
22% of cities will experience climate conditions that are not currently experienced by any existing major cities. As a general trend, we found that all the cities tend to shift towards the sub-tropics, with cities from the Northern hemisphere shifting to warmer conditions, on average ~1000 km south (velocity ~20 km.year-1), and cities from the tropics shifting to drier conditions.
Cities in the tropical regions will experience smaller changes in average temperature, relative to the higher latitudes. However, shifts in rainfall regimes will dominate the tropical cities. This is characterized by both increases in extreme precipitation events (+5% rainfall wettest month) and, the severity and intensity of droughts (-14% rainfall driest month). With more severe droughts, tropical cities will move towards the subtropics, i.e. towards drier climates
. However, the fate of major tropical cities remains highly uncertain because many tropical regions will experience unprecedented climate conditions. Specifically, of all 22% of cities that will experience novel climate conditions, most (64%) are located in the tropics. These include Manaus, Libreville, Kuala Lumpur, Jakarta, Rangoon, and Singapore.
In summary, at a global level, we observe a global geographic shift towards the subtropics, i.e. towards ~20 degrees of latitude.
Thanks much carl!
I'll be gone this morning until later and have a couple of comments.
I haven't looked at the study in great detail but will try to spend more time doing that.
My initial comments include:
This is based entirely on global climate model projections. Global climate models have not shown much skill in forecasting climate so far. They have all been too warm for one thing and the group that builds and uses them, refuses to reconcile them to reality.
Reality is a 1 degree temperature increase globally, mostly at higher latitudes over the last 100 years. That has caused some small changes in the climate in many places. However, the laws of meteorology involving the relationships between the land, oceans and sun have not changed and will not change. The same principles will still apply with much of the world slightly warmer and having the same weather systems that they did before.
How much difference will that make for different cities? The study makes it sound like some cities will be shifting out of their current climates into another type of climate, farther to the south. That has not happened in the last 100 years and will not happen in the next 100. The weather will certainly be warmer and be more like a city that is 100 miles farther south and that affect, is greatest in the highest latitudes where it is considered beneficial.
The vast majority of warming has taken place in the coldest places at the coldest times of year......not in the topics.
Global climate model can't predict weather or weather pattern regimes. Their limited usefullness is to tell us whether the planet as a whole will be warmer or not based on how much extra heat is trapped by increasing CO2., using mathematical equations that are thought to best represent a speculative theory that is simulated on a computer for 100 years.
A warmer atmosphere will be able to hold more moisture and more of it will evaporate off the oceans, so with certainty, there will be more precipitation. Who will get the most and who might get less? Impossible for models to provide information about that which can tell us specifics which relate to weather. Models actually increase precip in California for this reason. Odds are that this is the right idea based on them being along the warmer Pacific Ocean(the moisture source).
OK, I just noticed that this study is for the year 2050. That's 31 years from now. At the current rate of warming that would be around .4 deg C of warming.
Sometimes, all we need to do is use common sense to see that something doesn't add up.
What are the chances, that .4 deg of warming, concentrated in the high latitudes is going to be causing a shift in climate to all these cities?
The difference in temperature during that short time frame might be like those places having a climate that is like a city that is currently 50 miles to their south.
A bit less snow and more rain in places in the mid/higher latitudes but same weather patterns and mostly the same weather with temperatures, on average just a tad warmer than before.
Here is the actual warming and rate taking place in the real world:
The linear warming trend since January, 1979 remains at +0.13 C/decade.
"As a general trend, we found that all the cities tend to shift towards the sub-tropics, with cities from the Northern hemisphere shifting to warmer conditions, on average ~1000 km south (velocity ~20 km.year-1)"
This would be a shift in climate of around 12.4 miles/year..............124 miles in 10 years and 1,240 miles in 100 years.
I decided to do some math based on this using the real world rate of warming and 2 cities nearby.
Indianapolis IN has an average temperature of 53.1 F. Louisville KY, 100 miles south, has an average year round temperature of 58.2. This is a difference of 5.1 deg. F.
This is 3.25 deg. C
The real world rate of warming has been 1.3 deg. C/century. Based on the real world rate of warming and these 2 cities, it will take 250 years for the average temperature in Indianapolis to reach the average temperature in Louisville(go up 3.25 deg. C).
This study, however has the change in climate for a distance of 100 miles taking place in just 8 years based on their rate of 12.4 miles per year.
8 years based on the speculative model simulations in this study................250 years based on the the real world observations. Hmmmm, their calculations are more than 30 times greater then what has happened so far.
Edit: I actually under calculated the rate of change they are projecting by a factor of 2 by messing up the conversion from metric distance with my first calculation and fixed it.
In order to make my rate calculations based on the real world provable by real world facts/science/physics, I decided to go "the extra mile here"
Scroll up for that real world rate of 1.3 deg C/century....or use this link:
"The linear warming trend since January, 1979 remains at +0.13 C/decade."
Let's take another example of 2 cities. Wichita KS and Oklahoma City, OK. In this case, they are 161 miles away from each other, around 154 miles in the north/south direction.
Climate of Oklahoma City
The average mean temperature for Oklahoma City is 61.4 deg. F.
The average mean temperature of Wichita is 56.65 deg F.
This is a difference of 4.75 deg. C or converted to metric temps(divide by 1.6) and you get 2.97 deg.C(it's scientifically silly to be going out to hundreds of a degree doing a calculation like this because the sources of the data-average yearly temperature, vary by full degrees from year to year) so we'll round that number off the 3.0 deg. C.
Using the real world, linear rate of warming of 1.3 Deg C/century, it will take Witchita KS roughly 231 years for its average year round temperature to warm up by 3.0 deg. C, to the current average yearly temperature at Oklahoma City, 154 miles to the south.
Using the rate of this study, 12.4 miles/year. (20 km/year). It will take only 12.9 years for Witchita to warm up to the Oklahoma climate(154 miles divided by 12.4 miles/year = 12.9 years).
So in this example we have the difference in rates being 12.4 years in the study and 231 years in the real world, which yields a study rate that is 18.6 times greater than what has been happening the past 100 years.
These 2 cities are in the center of the country in the mid latitudes, where the meridional temperature gradient (change with latitude) is going to be steeper than areas along ocean coasts and farther to the south but less than cities in higher latitudes.
Regardless, the difference between what is really happening as proven with these real facts using real climate science and what these extreme scenarios we are being told about..........using climate model simulations of a future atmosphere based on computers programmed with speculative mathmatical equations is incredibly different.
In the current world of climate science, the gate keepers are using the computer simulations to promote a climate crisis..............which in reality is another climate optimum.
Current global temperatures are not quite as warm as they were in the Medieval Warm Period, the Roman Warm Period and the Minoan Warm Periods, 1,000, 2,000 and 3,500 years ago and have quite a ways to go to reach the Holocene Climate Optimum from 5,000 to 9,000 years ago.
The discussion at the link below provides the data to prove this real world climate science. Scroll down several pages to see the section on past temperatures:
Related to this:
Read the actual documents at this link that proves the fraudulence of this number.
What's interesting about how they categorized these scientists that supposedly are in the 97% is that this same technique for deriving that number, if applied to this atmospheric scientist's/operational meteorologist's discussions here as a climate realist/skeptic would include me in that 97% number of climate scientists.
Hugh? you might think.
Well, I believe probably half of the beneficial warming came from the physics of greenhouse gas warming from the entirely beneficial increase in CO2.
That clearly puts me in the 97% using the standards of the sources.
We could make an analogy using rain and farmers.
This Spring, too much rain caused severe planting delays of our corn and soybean crops in the Cornbelt. Rain for a couple of months in the planting delayed locations was bad news. It could be stated by manipulating the interpretation/meaning/intent, using these specific circumstances, that 97% of farmers believe that rain is bad without qualifiers............just that 97% of farmers all agreed, almost universally as the experts on growing crops that rain is bad and then spin that to tell us that when rain shows up in the weather forecast, even when there's a drought, that farmers expect their crops to face adversity because rain is bad.