TheClimateChanger

Throughout the entire Roman Kingdom and the Republic there was the so-called Subatlantic period, in which the Greek and Etruscan city-states also developed.[7] It was characterized by cool summers and mild, rainy winters.[7] At the same time there were a number of drastic winters, including the complete freezing of the Tiber in 398 BC, 396 BC, 271 BC and 177 BC.[8] In subsequent centuries the reports of occasional harsh winters became associated with flooding rather than ice on the Tiber.[8] Evidence for a cooler Mediterranean climate in 600 BC–100 BC comes from remains of ancient harbors at Naples and in the Adriatic which are located about one meter below current water level. Edward Gibbon, citing ancient sources, thought that the Rhine and the Danube were frequently frozen, facilitating the invasion of barbarian armies into the Empire "over a vast and solid bridge of ice".[9] Suggesting colder climate, Gibbon also contended that during Caesar's time reindeer were commonly found in the forests of modern Poland and Germany, whereas in his time reindeer were not observed south of the Baltic.[9] During the reign of Augustus the climate became warmer and the aridity in North Africa persisted.[10] The biotopes of Heterogaster urticae, which in Roman times occurred farther north than in the 1950s, suggest that in the early Empire mean July temperatures were at least 1 °C above those of the mid-20th-century.[3] Pliny the Younger wrote that wine and olives were cultivated in more northerly parts of Italy than in the previous centuries,[4] as did Saserna in the last century BC (both father and son).[8] Climate of ancient Rome - Wikipedia

More on the so-called Roman Warm Period. This excerpt from William Henry Dyer's Ancient Rome (1864).

But on your point, Sam Carana of Arctic News had previously made a good point that total warming may actually already be on the order of 2.3C if we include these preindustrial climate impacts. The total warming is dependent on the choice of baseline, but it should be evident that humanity has been altering the climate for a considerable amount of time prior to the Industrial Revolution. Obviously, the magnitude of such changes pale in comparison to those of the most recent 100 or 150 years; however, they are still very notable compared to natural variations. Arctic News: pre-industrial

I was thinking more on the lines of this study: Reassessment of pre-industrial fire emissions strongly affects anthropogenic aerosol forcing | Nature Communications Abstract Uncertainty in pre-industrial natural aerosol emissions is a major component of the overall uncertainty in the radiative forcing of climate. Improved characterisation of natural emissions and their radiative effects can therefore increase the accuracy of global climate model projections. Here we show that revised assumptions about pre-industrial fire activity result in significantly increased aerosol concentrations in the pre-industrial atmosphere. Revised global model simulations predict a 35% reduction in the calculated global mean cloud albedo forcing over the Industrial Era (1750–2000 CE) compared to estimates using emissions data from the Sixth Coupled Model Intercomparison Project. An estimated upper limit to pre-industrial fire emissions results in a much greater (91%) reduction in forcing. When compared to 26 other uncertain parameters or inputs in our model, pre-industrial fire emissions are by far the single largest source of uncertainty in pre-industrial aerosol concentrations, and hence in our understanding of the magnitude of the historical radiative forcing due to anthropogenic aerosol emissions.

Note that millions of acres of rangeland would burn each and every year. Late summer until the start of winter were clearly very hazy, smoky periods in the past. Even if this was mostly a seasonal phenomenon, it may be possible that aerosols emitted in this time frame have a greater climate impact than aerosols emitted at other times during the calendar year. Perhaps leading to autumn cooling and an earlier start to winter (more ice and snow). So our modeling simply looking at total emissions of aerosols might also be overlooking the fact that not all emissions are equal, and that emissions during the summer and fall are much more impactful on the global climate.

I think we also need to consider the possibility that our estimates for aerosol forcing are incorrect relative to preindustrial, before claiming instead that our estimate of climate sensitivity to carbon dioxide is incorrect. It seems like it was a very smoky, dusty time. Is it not possible that the globally averaged sky is now clearer than it was in the preindustrial times, and that aerosols have shifted from a cooling effect to a warming effect? If this is possible, then, it would not just be unmasking greenhouse warming but also directly contributing (that is, causing) warming relative to preindustrial in recent decades. The question to consider - are human changes in fire suppression and land management perhaps now outweighing human pollution in recent decades? With also a possibility that natural changes set on by warming are contributing... for instance, Sahara dust is predicted to decrease in response to warming. Has that already commenced relative to preindustrial?

Gotta love the 19th century woman trudging through the Blizzard of 1899 icon for 30F.

74 mph winds observed at Elkins Airport. Severe Thunderstorm Warning WVC077-093-161830- /O.NEW.KPBZ.SV.W.0001.250216T1800Z-250216T1830Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Pittsburgh PA 100 PM EST Sun Feb 16 2025 The National Weather Service in Pittsburgh has issued a * Severe Thunderstorm Warning for... Southeastern Preston County in northeastern West Virginia... North Central Tucker County in northeastern West Virginia... * Until 130 PM EST. * At 100 PM EST, a severe thunderstorm was located over Rowlesburg, moving northeast at 50 mph. HAZARD...70 mph wind gusts. SOURCE...Radar indicated. A 74 mph wind gust was reported at Elkins, WV IMPACT...Expect considerable tree damage. Damage is likely to mobile homes, roofs, and outbuildings. * Locations impacted include... Kingwood, Terra Alta, Rowlesburg, Albright, Tunnelton, Aurora, Cathedral State Park, Elgon and Cranesville. PRECAUTIONARY/PREPAREDNESS ACTIONS... Anyone outdoors should move to shelter inside a well-built structure and stay away from windows. This storm is capable of producing widespread damaging winds. && LAT...LON 3927 7969 3944 7980 3960 7950 3940 7948 3935 7948 3934 7949 3929 7949 3922 7965 TIME...MOT...LOC 1759Z 239DEG 44KT 3932 7967 THUNDERSTORM DAMAGE THREAT...CONSIDERABLE HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...0.00 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...70 MPH $$ McMullen

Severe Thunderstorm Warning WVC077-093-161830- /O.NEW.KPBZ.SV.W.0001.250216T1800Z-250216T1830Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Pittsburgh PA 100 PM EST Sun Feb 16 2025 The National Weather Service in Pittsburgh has issued a * Severe Thunderstorm Warning for... Southeastern Preston County in northeastern West Virginia... North Central Tucker County in northeastern West Virginia... * Until 130 PM EST. * At 100 PM EST, a severe thunderstorm was located over Rowlesburg, moving northeast at 50 mph. HAZARD...70 mph wind gusts. SOURCE...Radar indicated. A 74 mph wind gust was reported at Elkins, WV IMPACT...Expect considerable tree damage. Damage is likely to mobile homes, roofs, and outbuildings. * Locations impacted include... Kingwood, Terra Alta, Rowlesburg, Albright, Tunnelton, Aurora, Cathedral State Park, Elgon and Cranesville. PRECAUTIONARY/PREPAREDNESS ACTIONS... Anyone outdoors should move to shelter inside a well-built structure and stay away from windows. This storm is capable of producing widespread damaging winds. && LAT...LON 3927 7969 3944 7980 3960 7950 3940 7948 3935 7948 3934 7949 3929 7949 3922 7965 TIME...MOT...LOC 1759Z 239DEG 44KT 3932 7967 THUNDERSTORM DAMAGE THREAT...CONSIDERABLE HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...0.00 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...70 MPH $$ McMullen

Isn’t that the map for the snow this morning?

FWIW, the 12z run of the GFS has a look very consistent with this outlook.

That would be brutal. Let's hope CPC is right about this period. It looks like their outlook from yesterday assumed any major storm would scoot off the Mid-Atlantic coast.

Yes, the cold was most impressive relative to the mean in the southern U.S. West Virginia was the coldest state, recording the 12th coldest January on record, probably driven, in part, by unusually persistent snow coverage. The State of New York was actually 0.6F above the 20th century mean and ranked as 60th warmest January, per NCEI.

I was doing some more research on Toronto seasonal snowfall. Look at these historic winter snow totals from the 19th century. Those are some "old-fashioned" winters! March 1870 must have been insane - wow! 62.4 inches of snow, with a 26.8F mean temperature. 21.5" of snow from the 15th to 17th, and 20" from the 26th to 28th.

I am hoping this is overdone off to our northwest. Is it really plausible that Detroit could pick up 14 inches of snow in the next 5 days? I don't buy it. This first storm looks like a 2 to 4-inch deal up there, and the weekend event looks like it will bring P-type issues again. I don't see why the Kuchera would be so much more than 10:1. This looks like a 10:1 type setup for most areas given the marginal atmospheric profile.

Impressive, and coming in a very strong El Nino winter, similar to the January 2016 snow storm.

Meanwhile, it has been 4,429 days since the last calendar day snowfall of 6.2" or more at Dayton. At this point, I'm unsure whether Dayton will see a daily snowfall that high ever again. I initially believed this to be a record; however, I noticed xMacis culminates streaks at days with missing data. Allowing for missing days, two potentially longer stretches arise. Of course, one would have to examine those streaks to see whether the missing data is impacted the longevity. The last time Dayton saw a snowfall that high was Boxing Day of 2012. That's a long time!

Certainly a brutal start to February for Dayton. Since 1894, I could find only 5 years without at least some snowflakes flying in the first 10 days of the month.

I am always highly skeptical of the totals when they show that sharp linear cutoff along the south edge. I know Joe Bastardi has a saying "you have to be close enough to smell the sleet (or rain?)" but I don't think that's ever been true in our part of the world. Usually the mixed precipitation continues further north cutting down on totals, and there is usually an area where it's snowing but the ratios are pathetic in this type of a setup. It's a subtype of snow that's extremely moisture laden and not very puffy or air-filled and ineffective at accumulating where ratios could be as low as 6:1. Those super sharp cutoffs are usually reserved for the northern edge of the precipitation, like the January 2016 snowstorm. Or, of course, to a smaller extent, with occasional lake effect snow bands which tend to favor some of the northern and northwestern communities. So I'm not super impressed with this depiction, even if it is showing some heavy snow in the northern parts of the metro. I don't think going from inch or two in southern Allegheny, to 8-12 inches in northern Allegheny is a plausible outcome for this setup. More like an inch or two around Pittsburgh, to perhaps several inches up near I-80.

Coldest January in the U.S. since 1988, barely beating out 1994. I guess climate change is over (just kidding!). What they won't tell you is from 1895 to 1988, inclusive, a period of 94 years, fully 33 of them saw Januarys that are as cold or colder than this one! So that's more than 1 out of every 3 years, meaning this was largely a typical 20th century January. Something that happens more than 1 out of every 3 years is pretty much as normal as it gets. Proof: Tied with 1920 for 33rd coldest, meaning 33 years saw Januarys as cold or colder than this one until 1988. Yet it's been nearly 40 years since we've had a January as cold or colder than this one for the CONUS. Weird - it's almost like something has changed.

It would be nice to get back on the board again. After a fairly snowy start to January, there has only been 0.1" dating back to the 25th. And the last 30 days (1/12-2/10) have only measured a total of 6.3 inches. That's pretty crappy in what climatologically is the snowiest period in Pittsburgh.

The NAM shows a couple inches tomorrow for the metro area (particularly south), is that possible?

New special weather statement for parts of the Pittsburgh metro. My current temperature is 31.1F, so this is interesting. Lot of movement on that storm cell as well - 80 mph, wow! Special Weather Statement National Weather Service Pittsburgh PA 357 PM EST Sat Feb 8 2025 OHZ040-049-050-PAZ020-021-029-WVZ001-002-082145- Jefferson OH-Harrison OH-Carroll OH-Beaver PA-Allegheny PA- Washington PA-Brooke WV-Hancock WV- 357 PM EST Sat Feb 8 2025 ...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN HARRISON...NORTHERN JEFFERSON...SOUTHEASTERN CARROLL...SOUTHERN BEAVER...NORTHWESTERN WASHINGTON...CENTRAL ALLEGHENY...BROOKE AND HANCOCK COUNTIES THROUGH 445 PM EST... At 357 PM EST, Doppler radar was tracking a strong thunderstorm 10 miles southeast of Carrollton, moving east at 80 mph. HAZARD...Pea size hail. SOURCE...Radar indicated. IMPACT...Minor hail damage to vegetation is possible. Locations impacted include... Pittsburgh, Penn Hills, Mount Lebanon, Ross Township, McCandless Township, Moon Township, Weirton, Steubenville, Franklin Park, Shaler Township, North Side Pittsburgh, Baldwin, Upper St. Clair, Hampton Township, Scott Township, Wilkinsburg, Whitehall, Robinson Township, Dormont, and O`hara Township. This includes the following highways... Interstate 79 in Pennsylvania between mile markers 54 and 72. Parkway North between mile markers 1 and 13. Interstate 376 in Pennsylvania between mile markers 47 and 75. PRECAUTIONARY/PREPAREDNESS ACTIONS... If outdoors, consider seeking shelter inside a building. && LAT...LON 4034 8111 4052 8112 4060 8000 4049 7982 4036 8000 TIME...MOT...LOC 2057Z 266DEG 69KT 4044 8101 MAX HAIL SIZE...0.25 IN MAX WIND GUST...<30 MPH $$ Milcarek

Special Weather Statement National Weather Service Pittsburgh PA 322 PM EST Sat Feb 8 2025 OHZ039-040-048-049-082100- Tuscarawas OH-Harrison OH-Coshocton OH-Carroll OH- 322 PM EST Sat Feb 8 2025 ...A STRONG THUNDERSTORM WILL IMPACT NORTHERN HARRISON...NORTHEASTERN COSHOCTON...SOUTHERN CARROLL AND CENTRAL TUSCARAWAS COUNTIES THROUGH 400 PM EST... At 322 PM EST, Doppler radar was tracking a strong thunderstorm 7 miles southeast of Killbuck, or 8 miles south of Millersburg, moving east at 75 mph. HAZARD...Half inch hail. SOURCE...Radar indicated. IMPACT...Minor hail damage to vegetation is possible. Locations impacted include... New Philadelphia, Dover, Uhrichsville, Dennison, Sugarcreek, Gnadenhutten, Tuscarawas, Baltic, Scio, Midvale, Jewett, Warsaw, Amsterdam, Bowerston, Barnhill, Dellroy, Sherrodsville, Roswell, Stone Creek, and Leesville. This includes Interstate 77 in Ohio between mile markers 69 and 84. PRECAUTIONARY/PREPAREDNESS ACTIONS... If outdoors, consider seeking shelter inside a building. && LAT...LON 4045 8199 4044 8167 4053 8166 4058 8086 4056 8086 4056 8092 4047 8092 4047 8094 4042 8094 4042 8086 4034 8087 4033 8201 TIME...MOT...LOC 2022Z 266DEG 65KT 4043 8187 MAX HAIL SIZE...0.50 IN MAX WIND GUST...<30 MPH $$ Milcarek