Much Colder Than Normal March Pattern Continues

[bluewave]

Coldest March in NYC since 1984 at 37.7 and one of the coldest monthly temperature departures

of the 2000's so far. You have to go back to February 2007 for a lower monthly temperature

departure.

 

 

March 2014..............-4.8

January 2014............-4.0

December 2010........-4.5

January 2009............-4.1

February 2007..........-6.3

January 2004............-7.3

February 2003...........-4.5

January 2003............-4.6

December 2000.........-5.5

July 2000.................-4.5

[doncat]

Coldest March in NYC since 1984 at 37.7 and one of the coldest monthly temperature departures

of the 2000's so far. You have to go back to February 2007 for a lower monthly temperature

departure.

 

 

March 2014..............-4.8

January 2014............-4.0

December 2010........-4.5

January 2009............-4.1

February 2007..........-6.3

January 2004............-7.3

February 2003...........-4.5

January 2003............-4.6

December 2000.........-5.5

July 2000.................-4.5

Similar here with this March tying 1984 and beaten only by 1978 for cold during past 37 years, also the Jan-March period was 2nd coldest beaten only by 1978.

[bluewave]

Similar here with this March tying 1984 and beaten only by 1978 for cold during past 37 years, also the Jan-March period was 2nd coldest beaten only by 1978.

 

Very impressive to get this kind of cold for the first three months of the year after the record warmth two years ago.

 

NYC JFM

 

2014...-4.2

2012...+6.2

 

 

 

[forkyfork]

Coldest March in NYC since 1984 at 37.7 and one of the coldest monthly temperature departures

of the 2000's so far. You have to go back to February 2007 for a lower monthly temperature

departure.

 

 

March 2014..............-4.8

January 2014............-4.0

December 2010........-4.5

January 2009............-4.1

February 2007..........-6.3

January 2004............-7.3

February 2003...........-4.5

January 2003............-4.6

December 2000.........-5.5

July 2000.................-4.5

yet no record lows

[bluewave]

yet no record lows

 

The older Marches over 100 years ago when most of the record lows occurred were  just too cold to compete against.

 

[forkyfork]

The older Marches over 100 years ago when most of the record lows occurred were  just too cold to compete against.

 

Screen shot 2014-04-01 at 11.33.56 AM.png

EWR didn't set any either

[Brian5671]

yet no record lows

UHI

[Guest Pamela]

Definite cooling trend the last couple years at KNYC (monthly mean temperature)...

 

January 2012: 37.3 F

January 2014: 28.6 F

(8.7 F drop)

 

February 2012: 40.9 F

February 2014: 31.6 F

(9.3 F drop)

 

March 2012: 50.9 F

March 2014: 37.7 F

(13.2 F drop)

[pazzo83]

Definite cooling trend the last couple years at KNYC (monthly mean temperature)...

 

January 2012: 37.3 F

January 2014: 28.6 F

(8.7 F drop)

 

February 2012: 40.9 F

February 2014: 31.6 F

(9.3 F drop)

 

March 2012: 50.9 F

March 2014: 37.7 F

(13.2 F drop)

 

 

LMAO, two data points don't constitute a trend.  Have you ever taken a statistics class?

[Isotherm]

LMAO, two data points don't constitute a trend.  Have you ever taken a statistics class?

 

 

I'm sure he knows this; it was probably just meant to show the sharp contrast/significant difference between the years.

[pazzo83]

I'm sure he knows this; it was probably just meant to show the sharp contrast/significant difference between the years.

He said definite cooling trend.

[NorthShoreWx]

Most people are able to understand what William was trying to say.

[Allsnow]

Most people are able to understand what William was trying to say.

Pazzo is just hurt because William pissed in his Cheerios a few weeks ago

[pazzo83]

Most people are able to understand what William was trying to say.

 

Yes and he is wrong.  You don't get a trend with two data points.

[pazzo83]

Pazzo is just hurt because William pissed in his Cheerios a few weeks ago

 

This topic might be a bit above your head...

[Guest Pamela]

Definite cooling trend the last three years at KNYC (monthly mean temperature)...

January 2012: 37.3 F
January 2013: 35.1 F
January 2014: 28.6 F
(8.7 F drop)

February 2012: 40.9 F
February 2013: 33.9 F
February 2014: 31.6 F
(9.3 F drop)

March 2012: 50.9 F
March 2013: 40.1 F
March 2014: 37.7 F
(13.2 F drop)

[uncle W]

NYC average annual temp...

ten yr ave.temp....highest.....lowest.
1870's.........51.8..........53.6.........49.4
1880's.........51.6..........53.2.........49.3
1890's.........52.9..........54.6.........50.4
1900's.........53.1..........55.0.........50.7
1910's.........53.0..........55.0.........50.7
1920's.........53.1..........54.9.........51.2
1930's.........54.4..........55.8.........53.0
1940's.........54.3..........56.9.........51.9
1950's.........54.8..........57.0.........52.5
1960's.........54.2..........55.1.........53.0
1970's.........54.6..........56.1.........53.0
1980's.........55.1..........56.0.........54.0
1990's.........55.6..........57.2.........53.7
2000's.........55.1..........56.8.........53.4
2010's.........56.4..........57.3.........55.3

The 1870's and 80's had a steady 20 years averaging 51.7...
From the 1890's to the 1920's Central Park averaged a steady 53.0 for the 40 years... From the 1930's to the 1970's CP averaged a steady 54.5... The 1980's and 90's were warmer averaging 55.4... development of the city was greater in the 1890's, 1920's and 1960's/70's...each time the average annual temp went up a degree...the latest warming could be traced to development in New Jersey where the air has to travel over before it gets to NYC or is it just a temporary warming?...the 2010's were due for a cold year and 2014 could be the one...

[Guest Pamela]

NYC average annual temp...

ten yr ave.temp....highest.....lowest.

1870's.........51.8..........53.6.........49.4

1880's.........51.6..........53.2.........49.3

1890's.........52.9..........54.6.........50.4

1900's.........53.1..........55.0.........50.7

1910's.........53.0..........55.0.........50.7

1920's.........53.1..........54.9.........51.2

1930's.........54.4..........55.8.........53.0

1940's.........54.3..........56.9.........51.9

1950's.........54.8..........57.0.........52.5

1960's.........54.2..........55.1.........53.0

1970's.........54.6..........56.1.........53.0

1980's.........55.1..........56.0.........54.0

1990's.........55.6..........57.2.........53.7

2000's.........55.1..........56.8.........53.4

2010's.........56.4..........57.3.........55.3

The 1870's and 80's had a steady 20 years averaging 51.7...

From the 1890's to the 1920's Central Park averaged a steady 53.0 for the 40 years... From the 1930's to the 1970's CP averaged a steady 54.5... The 1980's and 90's were warmer averaging 55.4... development of the city was greater in the 1890's, 1920's and 1960's/70's...each time the average annual temp went up a degree...the latest warming could be traced to development in New Jersey where the air has to travel over before it gets to NYC or is it just a temporary warming?...the 2010's were due for a cold year and 2014 could be the one...

 

The Little Ice Age ended around 1890 so I wouldn't read too much into the temperatures then vs now...different dimensions applied...the 53 F average from 1890 to 1930 looks realistic...the 2.0 F degree increase between then and the 2000's can mostly be written off to urban expansion...the 56.4 F for the 2010's is of course, based on only three exceptionally warm years and should not be considered...

[bluewave]

The Little Ice Age ended around 1890 so I wouldn't read too much into the temperatures then vs now...different dimensions applied...the 53 F average from 1890 to 1930 looks realistic...the 2.0 F degree increase between then and the 2000's can mostly be written off to urban expansion...the 56.4 F for the 2010's is of course, based on only three exceptionally warm years and should not be considered...

 

You can blame UHI for roughly 30% of the rise in the temperatures at Central Park since 1900.

 

[Guest Pamela]

You can blame UHI for roughly 30% of the rise in the temperatures at Central Park since 1900.

 

Screen shot 2014-04-12 at 4.10.10 PM.png

 

Don't tell me what to think; I'll blame it for whatever amount I want.

[NorthShoreWx]

You can blame UHI for roughly 30% of the rise in the temperatures at Central Park since 1900.

 

Screen shot 2014-04-12 at 4.10.10 PM.png

 

That's a helpful graphic, but not definitive.  Among other things, there has probably also been some increase in UHI effect at some of the surrounding 23 stations.  I couldn't give a number, but would be willing to bet (assuming this chart is accurate) that more than 30% of city warming is due to increasing UHI.  There may also be other factors.

 

The only thing I would be fairly comfortable concluding from the graphic is that temperatures in the city rose faster than in surrounding areas most likely due to UHI.  I'm sure there is more at work than just UHI in warming city temperatures but not really confident that we can guess the magnitude of competing factors from this chart.

[bluewave]

That's a helpful graphic, but not definitive.  Among other things, there has probably also been some increase in UHI effect at some of the surrounding 23 stations.  I couldn't give a number, but would be willing to bet (assuming this chart is accurate) that more than 30% of city warming is due to increasing UHI.  There may also be other factors.

 

The only thing I would be fairly comfortable concluding from the graphic is that temperatures in the city rose faster than in surrounding areas most likely due to UHI.  I'm sure there is more at work than just UHI in warming city temperatures but not really confident that we can guess the magnitude of competing factors from this chart.

 

That study and many others have come to the same conclusion about UHI, so it's really nothing that involves guesswork. 

 

 

http://pubs.giss.nas...ffin_etal_1.pdf

 

We analyse historical (1900 – present) and recent (year 2002) data on New York city’s urban heat island (UHI) effect, to characterize changes over time and spatially within the city. The historical annual data show that UHI intensification is responsible for ∼1/3 of the total warming the city has experienced since 1900. The intensification correlates with a significant drop in windspeed over the century, likely due to an increase in the urban boundary layer as Manhattan’s extensive skyline development unfolded. For the current-day, using 2002 data, we calculate the hourly and seasonal strength of the city’s UHI for five different case study areas, including sites in Manhattan, Bronx, Queens and Brooklyn. We find substantial intra-city variation (∼2 °C) in the strength of the hourly UHI, with some locations showing daytime cool islands – i.e., temperatures lower than the average of the distant non-urban stations, while others, at the same time, show daytime heat islands. The variations are not easily explained in terms of land surface characteristics such as building stock, population, vegetation fraction or radiometric surface temperatures from remote sensing. Although it has been suggested that stations within urban parks will underestimate UHI, the Central Park station does not show a significant underestimate, except marginally during summer nights. The intra-city heat island variations in the residential areas broadly correlate with summertime electricity demand and sensitivity to temperature increases. This relationship will have practical value for energy demand management policy, as it will help prioritize areas for UHI mitigation.

 

 

The upper curve in Fig. 1a is the Central Park record, while the lower curve is the average of the 23 non-urban stations. Figure 1b explicitly shows the temperature offset, Turban–rural (year) between these two historical records. It reveals a growth of the Central Park UHI strength from 2.0 C in 1900 to 2.5 C today.

The relative strength of New York’s UHI in 1900, and subsequent modest growth of 0.5 C, is interesting given the intensive increase in urban infrastructure since that time and continu- ing today. Historical photographs show that the building heights around Central Park were quite low in 1900, compared to the tall structures today, with a much greater skyview then (Black 1973). The resulting reduction in skyview over time should lead to UHI enhancement through reduced net longwave cooling (Oke 1986). Given the vast scale of New York’s skyline de- velopment since 1900, one might a priori expect a larger increase than 0.5 C. It is possible though that the Central Park station, located 300 m from the nearest streets, was less impacted by skyview loss over time. Additionally, although New York’s urban landscape and building heights were different, the Manhattan island population in 1900 was even larger (1.85 million persons in 1900) than today (1.54 million in 2000), due to turn-of-century immigration. So to the extent that population is an indicator of UHI strength, the relative 1900 UHI magnitude may be partial- ly understandable.

 

The data in Fig. 1 thus suggest that of the total 1.5 C warming Central Park has experienced over the century, roughly 33% of it was due to an increase in the UHI strength

 

[donsutherland1]

 

That study and many others have come to the same conclusion about UHI, so it's really nothing that involves guesswork. 

 

 

http://pubs.giss.nas...ffin_etal_1.pdf

 

We analyse historical (1900 – present) and recent (year 2002) data on New York city’s urban heat island (UHI) effect, to characterize changes over time and spatially within the city. The historical annual data show that UHI intensification is responsible for ∼1/3 of the total warming the city has experienced since 1900. The intensification correlates with a significant drop in windspeed over the century, likely due to an increase in the urban boundary layer as Manhattan’s extensive skyline development unfolded. For the current-day, using 2002 data, we calculate the hourly and seasonal strength of the city’s UHI for five different case study areas, including sites in Manhattan, Bronx, Queens and Brooklyn. We find substantial intra-city variation (∼2 °C) in the strength of the hourly UHI, with some locations showing daytime cool islands – i.e., temperatures lower than the average of the distant non-urban stations, while others, at the same time, show daytime heat islands. The variations are not easily explained in terms of land surface characteristics such as building stock, population, vegetation fraction or radiometric surface temperatures from remote sensing. Although it has been suggested that stations within urban parks will underestimate UHI, the Central Park station does not show a significant underestimate, except marginally during summer nights. The intra-city heat island variations in the residential areas broadly correlate with summertime electricity demand and sensitivity to temperature increases. This relationship will have practical value for energy demand management policy, as it will help prioritize areas for UHI mitigation.

 

 

The upper curve in Fig. 1a is the Central Park record, while the lower curve is the average of the 23 non-urban stations. Figure 1b explicitly shows the temperature offset, Turban–rural (year) between these two historical records. It reveals a growth of the Central Park UHI strength from 2.0 C in 1900 to 2.5 C today.

The relative strength of New York’s UHI in 1900, and subsequent modest growth of 0.5 C, is interesting given the intensive increase in urban infrastructure since that time and continu- ing today. Historical photographs show that the building heights around Central Park were quite low in 1900, compared to the tall structures today, with a much greater skyview then (Black 1973). The resulting reduction in skyview over time should lead to UHI enhancement through reduced net longwave cooling (Oke 1986). Given the vast scale of New York’s skyline de- velopment since 1900, one might a priori expect a larger increase than 0.5 C. It is possible though that the Central Park station, located 300 m from the nearest streets, was less impacted by skyview loss over time. Additionally, although New York’s urban landscape and building heights were different, the Manhattan island population in 1900 was even larger (1.85 million persons in 1900) than today (1.54 million in 2000), due to turn-of-century immigration. So to the extent that population is an indicator of UHI strength, the relative 1900 UHI magnitude may be partial- ly understandable.

 

The data in Fig. 1 thus suggest that of the total 1.5 C warming Central Park has experienced over the century, roughly 33% of it was due to an increase in the UHI strength

 

 

Thanks for sharing this study, Bluewave.

[Guest Pamela]

 

That study and many others have come to the same conclusion about UHI, so it's really nothing that involves guesswork. 

 

 

http://pubs.giss.nas...ffin_etal_1.pdf

 

 

 

 

Hmmm published in the Netherlands...home to the well known Royal Netherlands Meteorological Institute...a veritable hot bed (pardon the pun) of global warming activism & written & researched at Columbia University...where any "anti-progressive" thought has been quietly stifled since Roosevelt (Teddy, not Franklin). The objectivity of the article is quite simply unquestionable!           

[NorthShoreWx]

 

That study and many others have come to the same conclusion about UHI, so it's really nothing that involves guesswork. 

 

 

http://pubs.giss.nas...ffin_etal_1.pdf

 

We analyse historical (1900 – present) and recent (year 2002) data on New York city’s urban heat island (UHI) effect, to characterize changes over time and spatially within the city. The historical annual data show that UHI intensification is responsible for ∼1/3 of the total warming the city has experienced since 1900. The intensification correlates with a significant drop in windspeed over the century, likely due to an increase in the urban boundary layer as Manhattan’s extensive skyline development unfolded. For the current-day, using 2002 data, we calculate the hourly and seasonal strength of the city’s UHI for five different case study areas, including sites in Manhattan, Bronx, Queens and Brooklyn. We find substantial intra-city variation (∼2 °C) in the strength of the hourly UHI, with some locations showing daytime cool islands – i.e., temperatures lower than the average of the distant non-urban stations, while others, at the same time, show daytime heat islands. The variations are not easily explained in terms of land surface characteristics such as building stock, population, vegetation fraction or radiometric surface temperatures from remote sensing. Although it has been suggested that stations within urban parks will underestimate UHI, the Central Park station does not show a significant underestimate, except marginally during summer nights. The intra-city heat island variations in the residential areas broadly correlate with summertime electricity demand and sensitivity to temperature increases. This relationship will have practical value for energy demand management policy, as it will help prioritize areas for UHI mitigation.

 

 

The upper curve in Fig. 1a is the Central Park record, while the lower curve is the average of the 23 non-urban stations. Figure 1b explicitly shows the temperature offset, Turban–rural (year) between these two historical records. It reveals a growth of the Central Park UHI strength from 2.0 C in 1900 to 2.5 C today.

The relative strength of New York’s UHI in 1900, and subsequent modest growth of 0.5 C, is interesting given the intensive increase in urban infrastructure since that time and continu- ing today. Historical photographs show that the building heights around Central Park were quite low in 1900, compared to the tall structures today, with a much greater skyview then (Black 1973). The resulting reduction in skyview over time should lead to UHI enhancement through reduced net longwave cooling (Oke 1986). Given the vast scale of New York’s skyline de- velopment since 1900, one might a priori expect a larger increase than 0.5 C. It is possible though that the Central Park station, located 300 m from the nearest streets, was less impacted by skyview loss over time. Additionally, although New York’s urban landscape and building heights were different, the Manhattan island population in 1900 was even larger (1.85 million persons in 1900) than today (1.54 million in 2000), due to turn-of-century immigration. So to the extent that population is an indicator of UHI strength, the relative 1900 UHI magnitude may be partial- ly understandable.

 

The data in Fig. 1 thus suggest that of the total 1.5 C warming Central Park has experienced over the century, roughly 33% of it was due to an increase in the UHI strength

 

 

 

I haven't had time to read the full article, but the way I am reading the quoted text, it seems to support what I was thinking in the earlier post, rather than reducing any doubt. 

 

Mind you I am not trying to phrase an AGW debate; just questioning the degree of accuracy that we should expect from this methodology for measuring UHI effect.  It still strikes me as an easy rough approximation.  Call me a cynic if you like, but I question everything.

 

Perhaps there is some clarification on what /how they are comparing in the paper.  I won't have time to read it until later.

[bluewave]

I haven't had time to read the full article, but the way I am reading the quoted text, it seems to support what I was thinking in the earlier post, rather than reducing any doubt. 

 

Mind you I am not trying to phrase an AGW debate; just questioning the degree of accuracy that we should expect from this methodology for measuring UHI effect.  It still strikes me as an easy rough approximation.  Call me a cynic if you like, but I question everything.

 

Perhaps there is some clarification on what /how they are comparing in the paper.  I won't have time to read it until later.

 

There are numerous papers out there on separating UHI from temperature changes from other sources. This isn't

an AGW debate since the issue isn't isn't about where  the remainder of warming is coming from beyond

UHI. That would be better suited for the climate change forum.

 

Here is a recent paper on the UHI effect for USA in general:

 

http://rhinohide.org/climate/publications/Hausfather/HausfatherMenne-UHI-2013.pdf

 

An assessment quantifying the impact of urbanization on temperature trends from the U.S. Historical Climatology Network (USHCN) is described. Stations were first classified as urban and nonurban (rural) using four different proxy measures of urbanity. Trends from the two station types were then compared using a pairing method that controls for differences in instrument type and via spatial gridding to account for the uneven distribution of stations. The comparisons reveal systematic differences between the raw (unadjusted) urban and rural temperature trends throughout the USHCN period of record according to all four urban classifications. According to these classifications, urbanization accounts for 14–21% of the rise in unadjusted minimum temperatures since 1895 and 6–9% since 1960. The USHCN version 2 homogenization process effectively removes this urban signal such that it becomes insignificant during the last 50–80 years. In contrast, prior to 1930, only about half of the urban signal is removed. Accordingly, the National Aeronautics and Space Administration Goddard Institute for Space Studies urban-correction procedure has essentially no impact on USHCN version 2 trends since 1930, but effectively removes the residual urban-rural temperature trend differences for years before 1930 according to all four urban proxy classifications. Finally, an evaluation of the homogenization of USHCN temperature series using subsets of rural-only and urban-only reference series from the larger U.S. Cooperative Observer (Coop) Network suggests that the composition of Coop stations surrounding USHCN stations is sufficiently “rural” to limit the aliasing of urban heat island signals onto USHCN version 2 temperature trends during homogenization.

[bluewave]

Hmmm published in the Netherlands...home to the well known Royal Netherlands Meteorological Institute...a veritable hot bed (pardon the pun) of global warming activism & written & researched at Columbia University...where any "anti-progressive" thought has been quietly stifled since Roosevelt (Teddy, not Franklin). The objectivity of the article is quite simply unquestionable!           

 

The point you are missing is that these figures can be independently verified, so I don't get why you are bringing

what you perceive their politics to be. 

[pazzo83]

Hmmm published in the Netherlands...home to the well known Royal Netherlands Meteorological Institute...a veritable hot bed (pardon the pun) of global warming activism & written & researched at Columbia University...where any "anti-progressive" thought has been quietly stifled since Roosevelt (Teddy, not Franklin). The objectivity of the article is quite simply unquestionable!           

 

You are an embarrassment to objective thought and reason. 

[uncle W]

the heat island is not just the five boroughs...it has become the tri state area...I think the uhi is greater than the 33% in this study...

[Guest Pamela]

You are an embarrassment to objective thought and reason. 

 

You are just a regular embarrassment...