Endless Summer

[afishinado]

pcray1231 wrote:
Just historical records, SE PA has warmed, especially Philly, although Philly itself is largely a heat island effect based on the location of NOAA's gauges, as it is anomalous compared to the surrounding area (Chester County has cooled, for instance), and as such would generally not be used in a proper model.

NC/NW PA has been about/slightly below average in the last 30-50 years or so, although still higher than the mid 1900's. There was a jump around 1970, but kind of stable before and after. That's just mean temperature, I'm not breaking it down by winter, summer, coldest streaks or hottest streaks. If you want to do that it looks like summers have been cooler and winters warmer, but drawing any conclusions on a specific spot is tentative at best.

That's not making any prediction whatsoever for the future, there are models that say any number of things. And yes, the earth has warmed and will continue to do so, I'm not a climate denier, in fact I was a climate researcher and statistician in a past life for NOAA. i.e. making sense of the data that's used in those models.

It's real difficult to discern ANY state/local effects, it's just noisy. There's one gauge in a county sized area, and if someone builds a parking lot next to it or a tree grows taller nearby, it skews the numbers a ton! The way you verify a small signal in a noisy system is simply gather a ton of data in multiple ways, and average it out. We have a ton of data. It can be conclusively said that on a global scale, the earth is warming. More likely than not PA will warm as well, because, more places will warm than cool.

And better evidence than any land based temperature gauge is sea surface temperatures measured by satellite. It isn't skewed by human land use changes around gauges. The sea is warming. Polar ice extent is another. It's diminishing. Sea level rise. It's rising. These are the best indicators of GLOBAL warming and measurement of how much. Yes, the average of the land based gauges tells the same overall story if you average out every station in every location, but it's SUPER common that on land based gauges to get one that's warming super fast and another 20 miles away that shows cooling. And how do you reconcile a 100 year temperature trend of an area when there were 3 reporting stations in that area in 1921 and there are 75 today, with each of them telling you something totally different? You can't.

I am not a climate change denier. Just a statistician. And the stats say don't draw conclusions based on one gauge or trend on a local level, because the signal to noise ratio sucks. Trust less noisy systems like the ocean. Or if using a noisy system, take an average of lot of locations and draw an overall conclusion rather than one for your one location.

According to the article below, all of SE PA (the Delaware and Lehigh Valley areas) has warmed, including Chester County. Where is any data or articles about Chester county cooling?

From the article >

On the whole, annual temperatures across Pennsylvania have been about 2 degrees Fahrenheit above normal over that time span. But data show Philadelphia has had the worst of it, averaging 3.4 degrees above normal. Moving up the Delaware River, Bucks and Northampton counties were right behind, at 3.2 degrees above normal.

Montgomery (3.1), Delaware (3.0), Lehigh (3.0), and Chester (2.7) round out the fastest-warming counties in the state.

https://www.buckscountycouriertimes.com/news/20191108/southeast-pennsylvania-is-warming-faster-than-rest-of-state-but-why

Changes in ocean circulation is believed to be the reason according to the above article.

 

[pcray1231]

Going by NOAA's official temperature gauges, which are behind a paywall for data downloads in excel format. It's just a list of thousands of numbers.

Your article says over the last 5 years, SE PA and the Lehigh Valley have been unusually warmer than the rest of the state.

That is correct, except the word "unusually" is kind of hard to define I suppose. 5 years isn't climate, it's weather, and nothing is "unusual" about 5 year deviations from the norm. Most natural oscillations, such as SOI (el nino, la nina stuff) generally have a 3-5 year time frame and have large effects, so it's bad form for any researcher not to include several such cycles in any average. Minimum 10 year, many use 20 year rolling averages.

But yeah, compared to the rest of the state (which wasn't all that warm in the last 5 years), Philly and the Lehigh Valley were considerably warmer. I'll take their word for it that the state as a whole was up 2 degrees in 5 years. When you have 6 or 7 counties listed over 3%, and many at 0, that's what you get.

A rolling average works like this. Some use 10 year, many use 20 year. You take the average daily temperature at any one location for 20 years. Whether you use highs or lows is part of the question. I like to look at both. Tomorrow you do it again. So only 1 day out of 7030 has changed. Instead of getting massive spikes that you can't see trends within, you get a smoother line. You've cut down a lot of noise so you can try to find the signal.

And then, ok, you have a signal. That's 1 station and you don't know what the signal is. If a station 10 miles away shows a different signal, something's screwy. Oh, hey, this station had a building go in next door. This one had a tree grow 3 feet and shade the gauge. That one over there was offline for calibration for a year, are the numbers prior to that suspect? And a couple of high school kids have been sitting on this one smoking out after school. So you don't use one station, you average a bunch together.

It's just... Difficult. Everyone wants information on how global warming effects their location. How does it effect SE PA vs. Central PA? It's kind of a preposterous question! And it's not easy to conclude anything, or deny anything, backed up by defensible data..
That's just the nature of noisy data. What is easier to stand behind are global averages over thousands of stations, sea temperature changes, sea level rise, polar ice coverage, stratospheric temperatures, etc. And all of the above give the same conclusion. The earth is warming.

I wrote and published a paper on ocean circulation effects. The "conveyor belt". When parsing data I found about a 30 year statistical cycle between the strength of the monsoon in Africa and North American temperatures. The connection is one thing, the cause is extremely tentative. But best guess was that a heavy monsoon season injects a slug of highly saline water from the Red Sea into the Indian Ocean (from wind direction). Saltier water is more dense, when that water follows the currents around Africa, up the Atlantic, through the Gulf Stream and to the North Atlantic, it affects the turnover in the North Atlantic and thus affects the NAO index, which is tied to eastern north american weather. That takes about 30 years for the water to get from Africa to the North Atlantic. God that was ages ago when I wrote that! The heat transport function of ocean currents is just massive, and slow. Something happening today affects weather a hundred years from now on the other side of the globe.

The chester county gauge I had looked at was "East Nantmeal Township". Probably some dude with a weather station, but he's NOAA certified.

 

[wgmiller]

afishinado wrote:
On the whole, annual temperatures across Pennsylvania have been about 2 degrees Fahrenheit above normal over that time span. But data show Philadelphia has had the worst of it, averaging 3.4 degrees above normal.

That seems logical, given the urban nature of Philadelphia and how structures absorb and retain heat longer, compared to suburban and rural areas. I'm sure there is data and research out that supports this theory, but don't have the time to look for it now.

 

[dryflyguy]

When I started this thread, I didn't really mean to have it turn into a climate change debate.
We've certainly done plenty of that on here before - and some turns turns political
I just wanted to share my observations of some peculiar things I've noticed - for whatever the reasons are.
But it is nice to have Pat get back to Pcraying us again!

I just got back from couple of days on the little J.
I thought the recent cool down in the weather might have perked things up there.
It didn't. According to all my buddies at Greene Hills Campground, and from my brief time on it, fishing is still very slow.
But at least those pesky mosquitoes have pretty much disappeared.
The leaf change still hasn't happened yet either - which is definitely later than normal

 

[Mike]

I would not have called that a debate. Rather, it was getting schooled by an expert.

 

[Mike]

By the way, when I say “ schooled” I consider that to be a positive thing for me and every other lay person with an interest. My staff and I ran one of those cooperative weather observer sites from 1991 until 2019 and Pat is right on regarding very localized temperature conditions such that one may need to average the values at sites that are in a larger geographical area in order to reduce noise in the data. Our site was selected by NOAA because of unusually cold temps in winter in comparison to the rest of SE Pa. Talk about noisy data on clear, windless nights at this low spot when there was snow on the ground in comparison to local sites on higher ground. Pat just gave me a lesson on how those data would have been handled.

 

[Acristickid]

I agree that the leaves are weird this year ,a good portion of the leaves here in the Laurel Highlands have turned brown fallen off rather than turn color.

Got an old apple tree, last year it yielded ONE apple. One. This year several hundred. Wonder if it was frost the year before that got it??

 

[wildtrout2]

Mike wrote:
I would not have called that a debate. Rather, it was getting schooled by an expert.

Here at PAFF, we we call it getting pcrayed. Always educational.

 

[lestrout]

Yo wild

Pcray tell

tl
les

 

[pcray1231]

The leaf changes, or lack thereof, have alot to do with moisture.

Not an expert on that. Can't excel sheet it, lol. But my personal observation is that a wet year (it certainly has been) leads to a rather muted and protracted fall display.

 

[dryflyguy]

pcray1231 wrote:
The leaf changes, or lack thereof, have alot to do with moisture.

Not an expert on that. Can't excel sheet it, lol. But my personal observation is that a wet year (it certainly has been) leads to a rather muted and protracted fall display.

That's pretty much what I've read about it too.
And that cooler temps in early fall contribute to better colors.
We've certainly had just the opposite for ideal conditions on both counts.

 

[JeffP]

In order to get a true picture of temperature changes, wouldn't one have to look at temperatures throughout the day rather than just highs and lows? Wouldn't it be possible for highs and low to not change much but temperature being higher or lower generally throughout the day? I know that would certainly complicate an already complex problem.
And are we willing to say that a 3 degree temperature change is not much? I though a 1 degree change was a lot. And why is it relevant at all that these changes were measured in a heat island at all? It's still man-made climate change.

 

[troutbert]

Species moving north is a strong indictor.

https://www.delawareonline.com/story/news/local/2015/09/05/iconic-fish-species-move-north-ocean-warms/71785270/

And it's not just fish, and not just in that region.

 

[troutbert]

Something familiar to flyfishers is hatch emergence timing.

The spring hatches generally hatch earlier now than in the past.

 

[gulfgreyhound]

Nice. Good for you ,apple butter was a favorite of mine as a kid. GG

 

[gulfgreyhound]

Nice. Good for you ,apple butter was a favorite of mine as a kid. GG

 

[gulfgreyhound]

https://www.npr.org/2021/10/15/1046313870/la-nina-winter-weather-us-temperatures-rainfall
This looks like an interesting winter setup. The last La Nina we had was a shorts and T shirt one. Fished all winter in that outfit with a light jacket to start the day. Less hurricanes as well. GG

 

[gulfgreyhound]

https://www.npr.org/2021/10/15/1046313870/la-nina-winter-weather-us-temperatures-rainfall
This looks like an interesting winter setup. The last La Nina we had was a shorts and T shirt one. Fished all winter in that outfit with a light jacket to start the day. Less hurricanes as well. GG

 

[FarmerDave]

Apparently this is the second year in a row for La Nina. I'm expecting this winter to be similar to last which was pretty mild.

 

[pcray1231]

In order to get a true picture of temperature changes, wouldn't one have to look at temperatures throughout the day rather than just highs and lows? Wouldn't it be possible for highs and low to not change much but temperature being higher or lower generally throughout the day? I know that would certainly complicate an already complex problem.

Sure, but they record highs and lows... Clouds generally lead to lower highs and higher lows. Can also play with do summers get warmer? Winters? Both? Neither, just summer gets longer and winter shorter? You can look at a billion things.

And are we willing to say that a 3 degree temperature change is not much?

For a day? lol. For a year, it ain't much.. For a 10+ year average, its a lot. Again, noisy in short term, but long term averages are more stable and thus a few degrees is noticable.

And why is it relevant at all that these changes were measured in a heat island at all? It's still man-made climate change.

Whats relevant depends what question you are asking. But no its not man made climate change.. It's man made. But localized weather change. And if you wanna do anything about it, determining cause DOES matter. If warming were all due to heat island effects, looking at greenhouse emissions wouldn't do ya much good..

If you are trying to measure global warming due to the greenhouse effect, the fact that more gauges are in urbanizing areas than in "greening" areas, heat island effects are a problem. Real effect, but not the one you're trying to measure, they just mask it. Which is why you go back to ocean temps, sea level, sea ice coverage, etc. Stuff thats harder to explain away as a local effect and more clearly points the finger at a global phenomenon. .