Hi all,
Now that I have figured out how to make PowerPoint presentations into Video, I can share with all of you what Es do each day.
The 6-Year Study clearly shows that Es are seasonal and peak around the Summer Solstice. Yes, there are other influences such as; meteors and a severe storm. BUT, the main influence is the tidal affect of the Sun on the Es layer around the solstice. (See the CSVHFS presentation).
Please view the PowerPoint showing a PropNET Capture Map of the 13 days around the Summer Solstice for this season. The background is the National Weather Service U.S. Radar Mosaic. It is in date order from June 15 to June 27. The solstice (June 21) is the middle day.
Each day is displayed in UTC hour order by day.
So if you are UTC time challenged, here is what the times mean:
00 UTC - Sunset approaches the East Coast
02 UTC - Sunset in the middle of the U.S.
04 UTC - Sunset on the West Coast
05-10 UTC Late night and twilight in North America
11 UTC Sunrise on the East Coast
12 UTC Sunrise in the middle of the U.S.
14 UTC Sunrise on the West Coast
18 UTC Solar Noon in the middle of the U.S.
20 UTC Afternoon throughout the U.S.
Also, be aware that the Sun rises earlier and sets later in the north.
So notice on the PowerPoint:
1. Es are spread out throughout the U.S at 00 'til 02 UTC.
2. Once the sun has set Es do occur, but are very very spotty. Actually this is the best time for early morning Es during the season, Overall, it is very quiet.
3. Once the sun rises (12 UTC), Es begin a rapid increase.
4. Intensity peaks close to 18 or 19 UTC as noon covers the central part of the U.S..
5. They begin to spread out late into the afternoon, but are not as intense. They are still excellent.
6. The second peak is occurring around 23 UTC.
Also, notice the Trans-Equatorial. It is much better this season and is probably associated with the rise of Solar Flux (Cycle 24). More on that later.
Enjoy. I am having fun doing this while the sun is scorching my grass.
73s
Art KA5DWI
PS.. Click on the arrows to the lower right for full screen
Monday, August 8, 2011
Sunday, August 7, 2011
Central States VHF Society Presentation
This is a test run for uploading PowerPoint Presentations to Video.
Please do not expect perfection. Use pause and play to control the slides.
I will edit this a little and re-submit it at a later date. I may add audio.
I presented this to the Central States VHF Society Conference on July 29, 2011. A paper was also published in the Proceedings.
Enjoy. I love talking about Es and entertain your questions and comments.
73s
Art Jackson - KA5DWI
Saturday, May 21, 2011
What happens in the E layer when 2 Meter Es occur.
Hi all,
Today (5/21) when the world was suppose to end...
Europe had a 2 Meter E opening.
This is what the E layer was doing. ..
No F2 could be read because the Es layer was so well ionized.
Weather had nothing to do with it. 73's Art
Today (5/21) when the world was suppose to end...
Europe had a 2 Meter E opening.
This is what the E layer was doing. ..
No F2 could be read because the Es layer was so well ionized.
Weather had nothing to do with it. 73's Art
Monday, April 4, 2011
What to Expect During the Spring/Summer Es Season
Here is a recap of what you can expect during this year's Spring/Summer Es Season.
Es appear around April 21th to the 25th now and then. The first full scale opening appears near May 9-11. By the end of May, Es are in full swing and will not decline until mid-August. Activity-wise, it peaks very near the Summer Solstice. It rises quickly and takes its time end.
This chart represents the daily active hours you can expect during the season. For about 6 weeks, beginning the third week of May you can expect as much as 12 hours of Es each day. Three days (6/13, 6/18 and 7/4) average 16 hours.
The next 4 charts show the probability of working 10-Meter Es each week of the season. The dates listed are the beginning of each week.
Es appear around April 21th to the 25th now and then. The first full scale opening appears near May 9-11. By the end of May, Es are in full swing and will not decline until mid-August. Activity-wise, it peaks very near the Summer Solstice. It rises quickly and takes its time end.
This chart represents the daily active hours you can expect during the season. For about 6 weeks, beginning the third week of May you can expect as much as 12 hours of Es each day. Three days (6/13, 6/18 and 7/4) average 16 hours.
The next 4 charts show the probability of working 10-Meter Es each week of the season. The dates listed are the beginning of each week.
Monday, December 20, 2010
A 5-Year 10-Meter Es Propagation Study Using PropNET - Final Part
Questions and Answers:
“Is Es propagation truly a seasonal occurrence?”
The answer derived from this study is definitely yes. The season begins within days of April 25 and progressively increases up to May 6, at which time it is in full swing and remains totally active until at least August 15. There is still a good chance that activity continues till the end of August. From the study, the season begins 8 weeks prior to the Summer Solstice and ends around 10 weeks after it.
“Since it has been determined to be seasonal, is activity evenly distributed around the Summer Solstice?”
After three years, I thought it was not. But now after 5 years I believe it is. The best part of the Es season is concentrated in the first half (8 weeks long) in a 4-week segment and one should make as much effort as one can during that period. Es are great from the 3rd week through the 6th week (May 9 – June 5). It might calm down slightly for the next four weeks around the solstice, but it in no way does it mean that the season is over. It is still very active during that lull. Once we arrive at Independence Day (July 4th), the season picks up again and it is not until around August 1 that a real decline is noticed. The season does not actually end until sometimes between August 15 and September 1. Statistically and graphically it has a slight right-skewed distribution of opportunities, still the median points of captures and opportunities rested near the Summer Solstice.
“It appears that one works most of their QSOs during the afternoon and evening hours. Is this the best time to work Es?”
No it is not. It appears this way only because most Hams are active late in the afternoon and evenings. The absolute best hours are from after sunrise till the actual Solar Noon hour. On weekends and days off from work, make every effort during the season to work Es during these hours. The late afternoon hours are also very good, distances covered are also better, but opportunities decline once the sun has set. Es are mostly diurnal (daytime phenomena). Es do occur in the late evening and early morning hours. When they do, it is a very special event. Enjoy it and make use of the opening.
“Do Es favor specific directions at certain times?”
Yes it does, and it has to do with the location of the sun. It appears that you follow the sun in order to apply where it is best. As the sun rises, the best conditions tend to be towards the North and East. Gradually, as the sun is high over the horizon, southern paths improve. Once the sun has moved beyond Solar Noon, western paths become better than eastern ones. Therefore, the tendency is that openings appear in the east and north first and then will develop towards the south and the west later on. The process starts over again in the afternoon as was displayed in the dual peak diurnal. Once the sun is setting, northern and western paths will decline in activity at a slower rate while southerly and easterly ones may drop off quickly.
“Can one predict when it is the best time to work real DX locations on Es?”
Yes…..
1. If the DX location is primarily east of you… Concentrate your efforts towards the DX station as your Sun has risen and then once again as the Sun’s Grey Line approaches the eastern DX locale.
2. If the DX location is west of you …Concentrate your efforts towards the western DX station as their Sun rises and then once again as your Sun sets.
3. For Northern and Southern DX paths ….Concentrate your efforts along the suns Grey Line as it leaves or approaches both locations.
This approach appears to produce better results.
“Do severe weather systems and the Jet Stream have any affects on Es propagation?”
Predominately it is small to absolutely none.
A weather system may influence Es propagation between two specific points (experienced here a few times), but I found it difficult to correlate its influence over the entire creation of the phenomena. This study covered 560 days of the Spring and Summer season, over a 5-year period. Of the entire seasonal total, I could only determine that an extremely small percentage of PropNET captures had anything to do with weather systems. In these 5 years, 2 of them were drought years with very little jet stream wind flow and little electrically active weather to speak of. If weather was the primary influence, the hourly charts would have represented trends indicative to weather affects. They clearly failed to do so. For three of the four years of the study, the morning daylight period was clearly the best times for Es propagation. Severe weather is a late afternoon, early evening occurrence. Captures in all four years never displayed the highest activity in the afternoon. In addition, Es would have also occurred at high levels in many other times of the season with varying levels. The study does not show that as is shown by its clear absence of captures in early April.
“Are there any other possible external influences that might affect Es?”
Probably meteors increase the probability of Es.
These were the actual daily captures of record for the 5 years of the study.
This is the potential meteor shower rates per hour for each day during the Es season.
Source: DL5BAC’s The Meteor Scatter Predictor Program (TMSP)
It was not perfect for all peaks of meteor activity, but many of the spikes in captures during the 5 years coincide along them. Meteor influence was brought to my attention at the end of the season when there was an increase in Es activity on July 29-30, August 2 and August 13-14 when one would think that activity should have been very limited.
“What might cause the overall lull in activity and probability during the weeks around the Summer Solstice?”
The high angle of the Sun during this period might have an affect on Mid-Latitude Es. The Nighttime probabilities actually peak during the solstice, therefore it points towards the peak during this period. Maybe the heat radiated off the earth, in addition to the high sun angle deters ionization of the Es layer to some extent. The final two years were minimum solar activity years. The lull was much less pronounced during this time.
“Is the term “Sporadic” a proper identification of the Es propagation phenomena?”
Absolutely not.
The Houghton Mifflin Dictionary defines “Sporadic” as:
1. Occurring at irregular intervals; having no pattern or order in time.
2. Appearing singly or at widely scattered localities, as a plant or disease.
3. Isolated; unique: a sporadic example
The 5 years of the study and the resulting charts show that Es display no such conditions of being Sporadic.
Therefore, we should use the opposite term, “Periodic”.
“Periodic” is defined as:
1. Having or marked by repeated cycles.
2. Happening or appearing at regular intervals.
3. Recurring or reappearing from time to time; intermittent.
Periodic appears to be a much better adjective used to describe Spring/Summer Es propagation.
Future Plans:
I encourage that someone in a different location than mine participate in PropNET each Es season. Efforts to improve data collection from the database created by LiveX will make it much easier to produce statistical analysis for more than one PropNET participant and I will look into this investigation in future years as long as there are an adequate number of participants.
I would like to see the research expanded to 6 and 2-Meters. I am sure we would see similar results experienced between 10 and 6-Meters. PropNET 2-Meter activity would produce a much more worthwhile propagation database than what APRS could accomplish. High population of users and the FM mode in APRS mask many of the propagation conditions that occur on VHF. PropNET could be more valuable than CW beacons.
I plan to list on a website a “Daily Probability” of Es conditions. I hope to have someone (or myself) to write a script very soon for general Ham Radio use that displays in date and time, the probability in percentage of experiencing an Es QSO on 10 Meters along with favorable directional data.
Glossary:
Afternoon Active - Most occur in the afternoon daylight hours.
Morning Active – Most occur in the morning daylight hours.
Averaging Data – It was used to smooth out peaks and lulls between actual days and better concentrate data gathered for hourly statistics. Solar Indices are displayed in running averages. It did not change the actual totals if the data displayed was accumulated.
Coefficient of Determination (R squared)- Is a measure used in statistics that indicates how well a calculated regression trend line approximates the actual data points. The scale is measured from 0.0 to 1.00. 1 reflects a perfect correlation.
Diurnal - Webster’s Dictionary defines this term as:
Recurring every day, occurring in the daytime, or opening during the day and closing at night.
Dual Peaked Diurnal – Two peaks of activity occur in the daylight hours.
Es Propagation – The bending of radio waves in the ionosphere at frequencies from approximately 10 – 230 MHz (25-50 MHz most common) by what is known as the E-Layer of the ionosphere (50-80 miles). Due to its lack of its predictability, it is often referred to as “Sporadic Es”. It is also known as “Short-Skip” because it propagates at shorter distances than normal F2 layer propagation at high frequencies.
Median – American Heritage Dictionary defines this term as:
Relating to, located in, or extending towards the middle
Probability Analysis – Based on the premise that one event occurs for a given time period. In the study, a single capture in an hour would have the same value at 100.
Right Skewed – Statistics term used to describe charted data. If most of the data volume is located to the left of center, it is considered right-skewed.
Right Tailed - Statistics term used to describe charted data. If the chartered data declines at a slower rate and time than it first rises, it is considered right tailed.
SE-Prop – DOS and Windows program developed by Jim Roop - K9SE that displays probable E-Cloud location and MUF between two stations.
Summer Solstice – It is the day that the Sun is directly over the Tropic of Cancer (approximately 23.5° North latitude). It is the highest elevation that the Sun will appear in the Northern Hemisphere. It marks the Winter Solstice in the Southern Hemisphere. When the same condition occurs in the Southern Hemisphere over the Tropic of Capricorn (approximately 23.5° South latitude), it is the Summer Solstice for the southern hemisphere and the Winter Solstice for the northern hemisphere.
Solar Noon Hour – The actual time (hour measured) that the Sun is due south. During Central Daylight Time it occurs at 13:18 or 1:18 PM.
Digisonde – A device that measures the values of returned high frequency radio signals transmitted and received in order to determine ionospheric layer altitudes. The University of Massachusetts Lowell Millstone Hill Digisonde is best known.
W6ELProp – Windows computer program developed by Sheldon C. Shallon, W6EL used for predicting ionospheric (sky-wave) propagation between any two locations on the earth on frequencies between 3 and 30 MHz. Earlier DOS versions were known as MINIPROP and MINIPROP Plus.
A Never-Ending Thank You to the PropNET Organization……..
Top 50 PropNET
Rank-Call-Grid Square-Captures
1 WD4RBX EM84NN 8713
2 WB8ILI EN82OQ 5933
3 K4RKM EM85VF 5160
4 W4JKL EM84AK 5026
5 K8VGL EM69UT 4752
6 AD4RX EL88OD 4443
7 KD5LWU DM57RI 2857
8 N7YG DM42NF 2655
9 K4EPS EL86UW 1752
10 NZ9Z EN64BD 1716
11 N4LR EM73QN 1626
12 KC9MEG EN52TI 1358
13 N4PSN EM84KP 1245
14 KI4EIZ EM63KN 1072
15 KI0GU EN35HF 974
16 WN4AMO EL98CW 861
17 KF6XA DM13JO 827
18 N8QLT EN82HL 707
19 KC6QJO DM05KH 701
20 N0OBG EM48RO 659
21 KC0EFC EM28OX 649
22 W3GYK EM85VF 620
23 WN3C FM19QC 539
24 W2EV FN03XD 529
25 AB0TJ DN60CN 514
26 WB8SKP EM56WR 509
27 WB4U EM94QU 493
28 W3NRG DM12JQ 491
29 NI5F EM42UF 459
30 K5BTV EM74WG 376
31 KF9KV EN52ET 374
32 W6CGH DM13BR 347
33 WA0JYF EN42EB 333
34 WB8SKP EN66TD 326
35 WB4JFI EM92XU 314
36 KC0TLN EM28QX 306
37 WV5L DM65PG 275
38 AB9MS EN42XN 268
39 KD5CFB EM40IQ 221
40 AI4NV EL87PX 192
41 K1HOP FN31SS 191
42 W4DDR EM85BW 177
43 NM4V FM06NR 176
44 NH7O BL10WP 162
45 NK8Q FN20GN 153
46 N5XYO DM90QQ 145
47 WD4ELG FM06LA 139
48 N2JR FM18CO 137
49 K3OMG EN82EI 126
50 W7IXZ DN05XJ 122
73s Art Jackson KA5DWI
“Is Es propagation truly a seasonal occurrence?”
The answer derived from this study is definitely yes. The season begins within days of April 25 and progressively increases up to May 6, at which time it is in full swing and remains totally active until at least August 15. There is still a good chance that activity continues till the end of August. From the study, the season begins 8 weeks prior to the Summer Solstice and ends around 10 weeks after it.
“Since it has been determined to be seasonal, is activity evenly distributed around the Summer Solstice?”
After three years, I thought it was not. But now after 5 years I believe it is. The best part of the Es season is concentrated in the first half (8 weeks long) in a 4-week segment and one should make as much effort as one can during that period. Es are great from the 3rd week through the 6th week (May 9 – June 5). It might calm down slightly for the next four weeks around the solstice, but it in no way does it mean that the season is over. It is still very active during that lull. Once we arrive at Independence Day (July 4th), the season picks up again and it is not until around August 1 that a real decline is noticed. The season does not actually end until sometimes between August 15 and September 1. Statistically and graphically it has a slight right-skewed distribution of opportunities, still the median points of captures and opportunities rested near the Summer Solstice.
“It appears that one works most of their QSOs during the afternoon and evening hours. Is this the best time to work Es?”
No it is not. It appears this way only because most Hams are active late in the afternoon and evenings. The absolute best hours are from after sunrise till the actual Solar Noon hour. On weekends and days off from work, make every effort during the season to work Es during these hours. The late afternoon hours are also very good, distances covered are also better, but opportunities decline once the sun has set. Es are mostly diurnal (daytime phenomena). Es do occur in the late evening and early morning hours. When they do, it is a very special event. Enjoy it and make use of the opening.
“Do Es favor specific directions at certain times?”
Yes it does, and it has to do with the location of the sun. It appears that you follow the sun in order to apply where it is best. As the sun rises, the best conditions tend to be towards the North and East. Gradually, as the sun is high over the horizon, southern paths improve. Once the sun has moved beyond Solar Noon, western paths become better than eastern ones. Therefore, the tendency is that openings appear in the east and north first and then will develop towards the south and the west later on. The process starts over again in the afternoon as was displayed in the dual peak diurnal. Once the sun is setting, northern and western paths will decline in activity at a slower rate while southerly and easterly ones may drop off quickly.
“Can one predict when it is the best time to work real DX locations on Es?”
Yes…..
1. If the DX location is primarily east of you… Concentrate your efforts towards the DX station as your Sun has risen and then once again as the Sun’s Grey Line approaches the eastern DX locale.
2. If the DX location is west of you …Concentrate your efforts towards the western DX station as their Sun rises and then once again as your Sun sets.
3. For Northern and Southern DX paths ….Concentrate your efforts along the suns Grey Line as it leaves or approaches both locations.
This approach appears to produce better results.
“Do severe weather systems and the Jet Stream have any affects on Es propagation?”
Predominately it is small to absolutely none.
A weather system may influence Es propagation between two specific points (experienced here a few times), but I found it difficult to correlate its influence over the entire creation of the phenomena. This study covered 560 days of the Spring and Summer season, over a 5-year period. Of the entire seasonal total, I could only determine that an extremely small percentage of PropNET captures had anything to do with weather systems. In these 5 years, 2 of them were drought years with very little jet stream wind flow and little electrically active weather to speak of. If weather was the primary influence, the hourly charts would have represented trends indicative to weather affects. They clearly failed to do so. For three of the four years of the study, the morning daylight period was clearly the best times for Es propagation. Severe weather is a late afternoon, early evening occurrence. Captures in all four years never displayed the highest activity in the afternoon. In addition, Es would have also occurred at high levels in many other times of the season with varying levels. The study does not show that as is shown by its clear absence of captures in early April.
“Are there any other possible external influences that might affect Es?”
Probably meteors increase the probability of Es.
These were the actual daily captures of record for the 5 years of the study.
This is the potential meteor shower rates per hour for each day during the Es season.
Source: DL5BAC’s The Meteor Scatter Predictor Program (TMSP)It was not perfect for all peaks of meteor activity, but many of the spikes in captures during the 5 years coincide along them. Meteor influence was brought to my attention at the end of the season when there was an increase in Es activity on July 29-30, August 2 and August 13-14 when one would think that activity should have been very limited.
“What might cause the overall lull in activity and probability during the weeks around the Summer Solstice?”
The high angle of the Sun during this period might have an affect on Mid-Latitude Es. The Nighttime probabilities actually peak during the solstice, therefore it points towards the peak during this period. Maybe the heat radiated off the earth, in addition to the high sun angle deters ionization of the Es layer to some extent. The final two years were minimum solar activity years. The lull was much less pronounced during this time.
“Is the term “Sporadic” a proper identification of the Es propagation phenomena?”
Absolutely not.
The Houghton Mifflin Dictionary defines “Sporadic” as:
1. Occurring at irregular intervals; having no pattern or order in time.
2. Appearing singly or at widely scattered localities, as a plant or disease.
3. Isolated; unique: a sporadic example
The 5 years of the study and the resulting charts show that Es display no such conditions of being Sporadic.
Therefore, we should use the opposite term, “Periodic”.
“Periodic” is defined as:
1. Having or marked by repeated cycles.
2. Happening or appearing at regular intervals.
3. Recurring or reappearing from time to time; intermittent.
Periodic appears to be a much better adjective used to describe Spring/Summer Es propagation.
Future Plans:
I encourage that someone in a different location than mine participate in PropNET each Es season. Efforts to improve data collection from the database created by LiveX will make it much easier to produce statistical analysis for more than one PropNET participant and I will look into this investigation in future years as long as there are an adequate number of participants.
I would like to see the research expanded to 6 and 2-Meters. I am sure we would see similar results experienced between 10 and 6-Meters. PropNET 2-Meter activity would produce a much more worthwhile propagation database than what APRS could accomplish. High population of users and the FM mode in APRS mask many of the propagation conditions that occur on VHF. PropNET could be more valuable than CW beacons.
I plan to list on a website a “Daily Probability” of Es conditions. I hope to have someone (or myself) to write a script very soon for general Ham Radio use that displays in date and time, the probability in percentage of experiencing an Es QSO on 10 Meters along with favorable directional data.
Glossary:
Afternoon Active - Most occur in the afternoon daylight hours.
Morning Active – Most occur in the morning daylight hours.
Averaging Data – It was used to smooth out peaks and lulls between actual days and better concentrate data gathered for hourly statistics. Solar Indices are displayed in running averages. It did not change the actual totals if the data displayed was accumulated.
Coefficient of Determination (R squared)- Is a measure used in statistics that indicates how well a calculated regression trend line approximates the actual data points. The scale is measured from 0.0 to 1.00. 1 reflects a perfect correlation.
Diurnal - Webster’s Dictionary defines this term as:
Recurring every day, occurring in the daytime, or opening during the day and closing at night.
Dual Peaked Diurnal – Two peaks of activity occur in the daylight hours.
Es Propagation – The bending of radio waves in the ionosphere at frequencies from approximately 10 – 230 MHz (25-50 MHz most common) by what is known as the E-Layer of the ionosphere (50-80 miles). Due to its lack of its predictability, it is often referred to as “Sporadic Es”. It is also known as “Short-Skip” because it propagates at shorter distances than normal F2 layer propagation at high frequencies.
Median – American Heritage Dictionary defines this term as:
Relating to, located in, or extending towards the middle
Probability Analysis – Based on the premise that one event occurs for a given time period. In the study, a single capture in an hour would have the same value at 100.
Right Skewed – Statistics term used to describe charted data. If most of the data volume is located to the left of center, it is considered right-skewed.
Right Tailed - Statistics term used to describe charted data. If the chartered data declines at a slower rate and time than it first rises, it is considered right tailed.
SE-Prop – DOS and Windows program developed by Jim Roop - K9SE that displays probable E-Cloud location and MUF between two stations.
Summer Solstice – It is the day that the Sun is directly over the Tropic of Cancer (approximately 23.5° North latitude). It is the highest elevation that the Sun will appear in the Northern Hemisphere. It marks the Winter Solstice in the Southern Hemisphere. When the same condition occurs in the Southern Hemisphere over the Tropic of Capricorn (approximately 23.5° South latitude), it is the Summer Solstice for the southern hemisphere and the Winter Solstice for the northern hemisphere.
Solar Noon Hour – The actual time (hour measured) that the Sun is due south. During Central Daylight Time it occurs at 13:18 or 1:18 PM.
Digisonde – A device that measures the values of returned high frequency radio signals transmitted and received in order to determine ionospheric layer altitudes. The University of Massachusetts Lowell Millstone Hill Digisonde is best known.
W6ELProp – Windows computer program developed by Sheldon C. Shallon, W6EL used for predicting ionospheric (sky-wave) propagation between any two locations on the earth on frequencies between 3 and 30 MHz. Earlier DOS versions were known as MINIPROP and MINIPROP Plus.
A Never-Ending Thank You to the PropNET Organization……..
Top 50 PropNET
Rank-Call-Grid Square-Captures
1 WD4RBX EM84NN 8713
2 WB8ILI EN82OQ 5933
3 K4RKM EM85VF 5160
4 W4JKL EM84AK 5026
5 K8VGL EM69UT 4752
6 AD4RX EL88OD 4443
7 KD5LWU DM57RI 2857
8 N7YG DM42NF 2655
9 K4EPS EL86UW 1752
10 NZ9Z EN64BD 1716
11 N4LR EM73QN 1626
12 KC9MEG EN52TI 1358
13 N4PSN EM84KP 1245
14 KI4EIZ EM63KN 1072
15 KI0GU EN35HF 974
16 WN4AMO EL98CW 861
17 KF6XA DM13JO 827
18 N8QLT EN82HL 707
19 KC6QJO DM05KH 701
20 N0OBG EM48RO 659
21 KC0EFC EM28OX 649
22 W3GYK EM85VF 620
23 WN3C FM19QC 539
24 W2EV FN03XD 529
25 AB0TJ DN60CN 514
26 WB8SKP EM56WR 509
27 WB4U EM94QU 493
28 W3NRG DM12JQ 491
29 NI5F EM42UF 459
30 K5BTV EM74WG 376
31 KF9KV EN52ET 374
32 W6CGH DM13BR 347
33 WA0JYF EN42EB 333
34 WB8SKP EN66TD 326
35 WB4JFI EM92XU 314
36 KC0TLN EM28QX 306
37 WV5L DM65PG 275
38 AB9MS EN42XN 268
39 KD5CFB EM40IQ 221
40 AI4NV EL87PX 192
41 K1HOP FN31SS 191
42 W4DDR EM85BW 177
43 NM4V FM06NR 176
44 NH7O BL10WP 162
45 NK8Q FN20GN 153
46 N5XYO DM90QQ 145
47 WD4ELG FM06LA 139
48 N2JR FM18CO 137
49 K3OMG EN82EI 126
50 W7IXZ DN05XJ 122
73s Art Jackson KA5DWI
A 5-Year 10-Meter Es Propagation Study Using PropNet - Part 10
The Final Level of Analysis:
Now that 5 years of data was collected and PropNET participation each year was consistent and the data displayed definitive trends, there still existed a few unexplained holes. Although I averaged combinations of days and hours, most of these charts displayed many peaks and valleys. It stirred up my curiosity and I decided to investigate it on a micro level.
Five years of participation had produced good probability data supported by capture numbers. It was proven that the higher the probability of Es, the number of captures during the occurrence was also higher. With this mind, the volume and incident data was combined to the level of a specific day and specific hour within it. The first attempt using 3-hour averages was not satisfactory. It failed to show extremes. In this analysis extremes need to be tracked in order to show the abnormalities.
In this final analysis, the hourly incidents (probability statistics) from April 25 to August 15 are graded on a 0 to 5 scale. A “0” ranking meant no opening, a ranking of “5” meant an opening all five years. Next, the hourly capture rate for each hour it was open was ranked in a similar manner. The hourly rate was based on the number of annual openings for that hour, not for the 5 year period. For example, if at 15:00 on May 23rd captures were recorded for 3 out of 5 years and a total of 60 captures occurred, a rate of 20 was assigned and applied to a similar scale (0-5).
The final process was to apply a scale based on the overall merit given from both probability and capture rates. The end result identified those events that appear to be special year to year during the Es season.
The Activity Scales:
The first activity scale applied to each hour of each day is one of probability. The low end (violet) will indicate no activity in 5 years. The high end (burnt orange) indicates an opening all five years.
The second activity scale is for capture rate when an opening occurred. It is based on the hourly capture rate as a ratio of the hours open.
The “Overall Rating Scale” is based on the combination of both the probability and capture rate scale. If there was no activity found, the “No Activity” (violet) is assigned. If one opening in five years with 6 or less captures occurred it was assigned “Light” (blue).
When viewing and interpreting these scales whenever it is yellow, orange or burnt orange (good to extreme) are the best times to operate. You will find that this occurs for most of the daytime periods into the median of the Es season.
The “Probable PNP No.” is a representation of the probable number of PropNET participants captured during the event. It may have been less, and possibly more and based on normal PropNET operating procedures.
The Chart:
The first row is the date of the season and the number of days prior to or after the Summer Solstice. The second row is the overall rating for each hour. Each date is displayed from local daylight saving time 12:00AM midnight to 11:00 PM. The third row is the probability rating. The number displayed was the years that an opening occurred. The fourth and final row was the hourly capture rate for those years open.
The results were somewhat startling. There are active days with good to extreme conditions, preceded or followed by poor ones. As this data was compiled, I realized that several of the days that had “Excellent” and “Extreme” conditions were days that I had experienced excellent VHF openings in the past.
By using this method of assessment and additional ranking of the daily results, the best days of each season can be identified. The DX enthusiast can now concentrate on individual days that historically produce excellent results.
60 days (slightly more than half) within the Es season have been identified as to being historically active days. In this review, an attempt to specifically detail traits will be attempted.
Es Activity Calendar:
Now that five years of data was collected, I was able to distinguish those days during the season that displayed excellent conditions. I have identified and ranked the 20 best days of the season for the following criteria:
1. High Rates – When open, a high rate of captures occurred.
2. High Activity – For the 5 years measured, a high number capture rate occurred overall.
3. High Probability – For the 5 years measured, a high number of open hours occurred.
4. Top 20 - Based on the 3 prior measurements, these days were within the top 20 days in the season.
5. Top 60 - Based on the 3 prior measurements, these days were within the top 60 days in the season.
The Best 20 Days of the Season:
The following dates are ranked from the 1st to the 20th.
6/16, 6/30, 7/8, 6/4, 6/3, 7/29, 6/5, 5/22, 6/29, 6/19
6/28, 7/13, 7/7, 6/15, 5/28, 6/13, 7/12, 7/28, 6/12, 6/23
1st Quartile Spring/Summer Es Season (April 25 – May 22):
The scale charting begins at 7:00PM on April 24. It signifies 00:00 UTC April 25. As noted, Es activity is very light and in five years measured, openings occurred for the most part only in one single year. The first evidence of any “good” level of Es activity occurs on the afternoon of May 4. The May 3-5 range shows the elevated levels. The first excellent conditions (orange) occur on May 9 and 10. The openings on this date occurred for only 2 to 3 years but when it was, the capture rates were at extreme levels (burnt-orange).
Activity levels improve and do have some periods less active. With the exception of the May 9-11 spark, the best conditions are during daylight hours.
Es Activity Calendar: April 25 – May 22
May 2: High Rates
May 3: High Rates Top 60
May 5: High Rates
May 7: High Rates
May 8: High Rates
May 9: High Rates High Activity Top 60
May 10: High Rates Top 60
May 11: Top 60
May 15: Top 60
May 20: Top 60
May 22: High Activity Top 20
2nd Quartile Spring/Summer Es Season (May 23- June 21):
The scale charting begins at 00:00 Local Daylight Time (Central) May 23. Es activity during each daytime period is very good (Yellow) in the five years measured. A few excellent hourly openings (Orange) will occur during daylight hours for most days in the quartile. The first evidence of extreme conditions (Burnt-Orange) in Es activity occurs on the morning of June 4-5. Some lulls in activity occur during this period, but are short-lived. 8 of the 20 top activity days occur in this quartile.
The best day of each Spring/Summer Es season is June 16. For 5 five years this date is highly ranked in probability, high hourly capture rates when open, and general high activity overall. The period from June 3 to June 17 are the best times of the season and should be the focus of all DX’ing activities.
Es Activity Calendar: May 23 – June 21
May 24: Top 60
May 26: High Probability Top 60
May 27: Top 60
May 28: High Activity Top 20
May 29: Top 60
May 30: High Probability Top 60
May 31 High Probability Top 60
June 1: Top 60
June 2: High Probability Top 60
June 3: High Activity High Rates Top 20
June 4: High Activity High Rates Top 20
June 5: High Probability High Activity Top 20
June 6: Top 60
June 8: High Probability High Activity
June 9: High Activity High Rates Top 60
June 10: High Rates Top 60
June 12: High Probability Top 20
June 13: High Probability Top 20
June 14: Top 60
June 15: High Probability High Activity Top 20
June 16: High Probability High Activity High Rates Top 20
June 17: High Probability Top 60
June 18: Top 60
June 19: High Activity Top 60
June 21: High Probability Top 60
3rd Quartile Spring/Summer Es Season (June 22 – July 20):
The scale charting begins at 00:00 Local Daylight Time (Central) June 22. Es activity during each daytime period remains very good (Yellow) in the five years measured. Excellent hourly openings (Orange) will occur during daylight hours for about 3/4th of the days in the quartile. A few lulls do occur. Extreme conditions (Burnt-Orange) in Es activity occur midday on June 30. As in the prior quartile, 8 of the 20 top activity days occur also in this one. The second and thirds best activity days of each Spring/Summer Es season are June 30 and July 8.
Es Activity Calendar: June 22 – July 20
June 22: High Probability Top 60
June 23: High Activity Top 20
June 24: High Probability Top 60
June 25: High Probability Top 60
June 26: High Probability Top 60
June 27: Top 60
June 28: High Activity High Rates Top 20
June 29: High Activity High Rates Top 20
June 30: High Activity High Rates Top 20
July 1: High Rates Top 60
July 3: Top 60
July 4: High Probability
July 5: Top 60
July 6: Top 60
July 7: High Probability High Activity Top 20
July 8: High Probability High Activity Top 20
July 9: High Probability Top 60
July 12: High Probability High Rates Top 20
July 13: High Activity High Rates Top 20
July 14: Top 60
July 16: Top 60
July 17: Top 60
July 19: High Activity Top 60
4th Quartile Spring/Summer Es Season (July 21 – August 15):
The scale charting begins at 00:00 Local Daylight Time (Central) July 21. During this period, Es begin a general decline. Still, Es activity during the daytime remain very good (Yellow) well into August. Excellent hourly openings (Orange) occur on July 28 and 29. July 29 has had a history of being one of the top 10 days of the season. Daily lulls become more common place, but no clear end of the season appears until August 15. Extreme conditions (Burnt-Orange) in Es activity do not occur during this period, although excellent conditions will occur as late as August 12. Only 2 of the top 20 and 7 of the top 60 activity days occur in the 4th quartile. The Es season ends quietly within 2 weeks after August 15.
Es Activity Calendar: July 21 – August 15
July 25 Top 60
July 27 Top 60
July 28 High Activity High Rates Top 20
July 29 High Activity High Rates Top 20
August 2 Top 60
August 3 Top 60
August 12 Top 60
Probabilities 8/15 – 8/28:
Beginning 8/15, Es activity begins to decline rapidly. As noted, it is not unusual to experience very good conditions now and then for an hour or two.
Next: The Final Recap, Helpers, Summary, Glossary
Now that 5 years of data was collected and PropNET participation each year was consistent and the data displayed definitive trends, there still existed a few unexplained holes. Although I averaged combinations of days and hours, most of these charts displayed many peaks and valleys. It stirred up my curiosity and I decided to investigate it on a micro level.
Five years of participation had produced good probability data supported by capture numbers. It was proven that the higher the probability of Es, the number of captures during the occurrence was also higher. With this mind, the volume and incident data was combined to the level of a specific day and specific hour within it. The first attempt using 3-hour averages was not satisfactory. It failed to show extremes. In this analysis extremes need to be tracked in order to show the abnormalities.
In this final analysis, the hourly incidents (probability statistics) from April 25 to August 15 are graded on a 0 to 5 scale. A “0” ranking meant no opening, a ranking of “5” meant an opening all five years. Next, the hourly capture rate for each hour it was open was ranked in a similar manner. The hourly rate was based on the number of annual openings for that hour, not for the 5 year period. For example, if at 15:00 on May 23rd captures were recorded for 3 out of 5 years and a total of 60 captures occurred, a rate of 20 was assigned and applied to a similar scale (0-5).
The final process was to apply a scale based on the overall merit given from both probability and capture rates. The end result identified those events that appear to be special year to year during the Es season.
The Activity Scales:
The first activity scale applied to each hour of each day is one of probability. The low end (violet) will indicate no activity in 5 years. The high end (burnt orange) indicates an opening all five years.
The second activity scale is for capture rate when an opening occurred. It is based on the hourly capture rate as a ratio of the hours open.
The “Overall Rating Scale” is based on the combination of both the probability and capture rate scale. If there was no activity found, the “No Activity” (violet) is assigned. If one opening in five years with 6 or less captures occurred it was assigned “Light” (blue).
When viewing and interpreting these scales whenever it is yellow, orange or burnt orange (good to extreme) are the best times to operate. You will find that this occurs for most of the daytime periods into the median of the Es season.
The “Probable PNP No.” is a representation of the probable number of PropNET participants captured during the event. It may have been less, and possibly more and based on normal PropNET operating procedures.
The Chart:
The first row is the date of the season and the number of days prior to or after the Summer Solstice. The second row is the overall rating for each hour. Each date is displayed from local daylight saving time 12:00AM midnight to 11:00 PM. The third row is the probability rating. The number displayed was the years that an opening occurred. The fourth and final row was the hourly capture rate for those years open.
The results were somewhat startling. There are active days with good to extreme conditions, preceded or followed by poor ones. As this data was compiled, I realized that several of the days that had “Excellent” and “Extreme” conditions were days that I had experienced excellent VHF openings in the past.
By using this method of assessment and additional ranking of the daily results, the best days of each season can be identified. The DX enthusiast can now concentrate on individual days that historically produce excellent results.
60 days (slightly more than half) within the Es season have been identified as to being historically active days. In this review, an attempt to specifically detail traits will be attempted.
Es Activity Calendar:
Now that five years of data was collected, I was able to distinguish those days during the season that displayed excellent conditions. I have identified and ranked the 20 best days of the season for the following criteria:
1. High Rates – When open, a high rate of captures occurred.
2. High Activity – For the 5 years measured, a high number capture rate occurred overall.
3. High Probability – For the 5 years measured, a high number of open hours occurred.
4. Top 20 - Based on the 3 prior measurements, these days were within the top 20 days in the season.
5. Top 60 - Based on the 3 prior measurements, these days were within the top 60 days in the season.
The Best 20 Days of the Season:
The following dates are ranked from the 1st to the 20th.
6/16, 6/30, 7/8, 6/4, 6/3, 7/29, 6/5, 5/22, 6/29, 6/19
6/28, 7/13, 7/7, 6/15, 5/28, 6/13, 7/12, 7/28, 6/12, 6/23
1st Quartile Spring/Summer Es Season (April 25 – May 22):
The scale charting begins at 7:00PM on April 24. It signifies 00:00 UTC April 25. As noted, Es activity is very light and in five years measured, openings occurred for the most part only in one single year. The first evidence of any “good” level of Es activity occurs on the afternoon of May 4. The May 3-5 range shows the elevated levels. The first excellent conditions (orange) occur on May 9 and 10. The openings on this date occurred for only 2 to 3 years but when it was, the capture rates were at extreme levels (burnt-orange).
Activity levels improve and do have some periods less active. With the exception of the May 9-11 spark, the best conditions are during daylight hours.
Es Activity Calendar: April 25 – May 22
May 2: High Rates
May 3: High Rates Top 60
May 5: High Rates
May 7: High Rates
May 8: High Rates
May 9: High Rates High Activity Top 60
May 10: High Rates Top 60
May 11: Top 60
May 15: Top 60
May 20: Top 60
May 22: High Activity Top 20
2nd Quartile Spring/Summer Es Season (May 23- June 21):
The scale charting begins at 00:00 Local Daylight Time (Central) May 23. Es activity during each daytime period is very good (Yellow) in the five years measured. A few excellent hourly openings (Orange) will occur during daylight hours for most days in the quartile. The first evidence of extreme conditions (Burnt-Orange) in Es activity occurs on the morning of June 4-5. Some lulls in activity occur during this period, but are short-lived. 8 of the 20 top activity days occur in this quartile.
The best day of each Spring/Summer Es season is June 16. For 5 five years this date is highly ranked in probability, high hourly capture rates when open, and general high activity overall. The period from June 3 to June 17 are the best times of the season and should be the focus of all DX’ing activities.
Es Activity Calendar: May 23 – June 21
May 24: Top 60
May 26: High Probability Top 60
May 27: Top 60
May 28: High Activity Top 20
May 29: Top 60
May 30: High Probability Top 60
May 31 High Probability Top 60
June 1: Top 60
June 2: High Probability Top 60
June 3: High Activity High Rates Top 20
June 4: High Activity High Rates Top 20
June 5: High Probability High Activity Top 20
June 6: Top 60
June 8: High Probability High Activity
June 9: High Activity High Rates Top 60
June 10: High Rates Top 60
June 12: High Probability Top 20
June 13: High Probability Top 20
June 14: Top 60
June 15: High Probability High Activity Top 20
June 16: High Probability High Activity High Rates Top 20
June 17: High Probability Top 60
June 18: Top 60
June 19: High Activity Top 60
June 21: High Probability Top 60
3rd Quartile Spring/Summer Es Season (June 22 – July 20):
The scale charting begins at 00:00 Local Daylight Time (Central) June 22. Es activity during each daytime period remains very good (Yellow) in the five years measured. Excellent hourly openings (Orange) will occur during daylight hours for about 3/4th of the days in the quartile. A few lulls do occur. Extreme conditions (Burnt-Orange) in Es activity occur midday on June 30. As in the prior quartile, 8 of the 20 top activity days occur also in this one. The second and thirds best activity days of each Spring/Summer Es season are June 30 and July 8.
Es Activity Calendar: June 22 – July 20
June 22: High Probability Top 60
June 23: High Activity Top 20
June 24: High Probability Top 60
June 25: High Probability Top 60
June 26: High Probability Top 60
June 27: Top 60
June 28: High Activity High Rates Top 20
June 29: High Activity High Rates Top 20
June 30: High Activity High Rates Top 20
July 1: High Rates Top 60
July 3: Top 60
July 4: High Probability
July 5: Top 60
July 6: Top 60
July 7: High Probability High Activity Top 20
July 8: High Probability High Activity Top 20
July 9: High Probability Top 60
July 12: High Probability High Rates Top 20
July 13: High Activity High Rates Top 20
July 14: Top 60
July 16: Top 60
July 17: Top 60
July 19: High Activity Top 60
4th Quartile Spring/Summer Es Season (July 21 – August 15):
The scale charting begins at 00:00 Local Daylight Time (Central) July 21. During this period, Es begin a general decline. Still, Es activity during the daytime remain very good (Yellow) well into August. Excellent hourly openings (Orange) occur on July 28 and 29. July 29 has had a history of being one of the top 10 days of the season. Daily lulls become more common place, but no clear end of the season appears until August 15. Extreme conditions (Burnt-Orange) in Es activity do not occur during this period, although excellent conditions will occur as late as August 12. Only 2 of the top 20 and 7 of the top 60 activity days occur in the 4th quartile. The Es season ends quietly within 2 weeks after August 15.
Es Activity Calendar: July 21 – August 15
July 25 Top 60
July 27 Top 60
July 28 High Activity High Rates Top 20
July 29 High Activity High Rates Top 20
August 2 Top 60
August 3 Top 60
August 12 Top 60
Probabilities 8/15 – 8/28:
Beginning 8/15, Es activity begins to decline rapidly. As noted, it is not unusual to experience very good conditions now and then for an hour or two.
Next: The Final Recap, Helpers, Summary, Glossary
Sunday, December 19, 2010
A 5-Year 10-Meter Es Propagation Study Using PropNET - Part 9
Hour to Hour Probabilities by Week:
The final analysis performed using probabilities was to compare the hour-to-hour trends of each week in the Spring/Summer Es season. With the volume and sampling, we should be able to identify where changes may occur from week to week of the season. Also, if the data accumulated was reliable, did it provide consistent and reasonable results?
Three Week Periods:
The following chart displays probabilities of working Es in 3-week segments from the beginning to the end of the season. The chart clearly details that the 6 weeks prior to and then after the Summer Solstice (12 weeks total) are the best periods for Es. The one fact that is evident is that during this 12 week period there is not much difference between them.
Weeks 1 – 4:
Week 1 (4/25-5/1) starts the Es season with some limited activity in the daytime hours. In Week 2 the best opportunity is in the late afternoon. Probabilities average less than 9% for Week 1 that on any hour a 10-Meter Es PropNET capture can occur. Probabilities almost double (over 16%) Week 2 and will favors afternoon times.
Probabilities more than double between the 2nd and 3rd weeks. Activity this 3rd week of the season clearly favors morning Es activity and typically forms a dual-diurnal pattern to be seen for other active weeks. Due to increased activity the final year of the study, the 4th week increased due to steady opportunities during the afternoon hours. Most of these weekly periods showed higher probabilities in the latter years of the study.
Weeks 5 – 8:
These are the weeks approaching the Summer Solstice. Probabilities in Week 5 increase over 8% to over 50% overall. Week 6 has the third highest probability of the Es season (near 58%) and had the highest of the season prior to the final year. The local 10 AM through 1 PM hours have probabilities of a 10-Meter PropNET capture at or above 90%.
Despite the high activity of the 6th week of the season, the 7th week (6/06) drops off over 7%. The drop off occurs during the morning hours. Week 8 returns to the level of Week 6 and has a rise in twilight activity that shows that the Summer Solstice is the peak of the season. Once again, this did not show until the latter years of the study.
Weeks 9 – 12:
Week 9 (6/20) is the week than contains the Summer Solstice. It changes little from Week 8 as there is a less than 1% increase, but the week is more morning active. There is a significant (more than 10%) decrease in Week 10, followed by a healthy resurgence of 12.6% in Week 11. This is the week that contains the Independence Day (July 4th) holiday and traditionally is known to be a very active week for Es propagation. Week 12 is unusual in that it declines in afternoon and evening activity. Most week to week declines have occurred during the morning hours.
Weeks 13 – 18:
The usual “morning decline” pattern occurs again in Week 13. Week 14 has a surge in activity is as Week 10. The sudden increase is noticeable from year to year. July 29 is usually active and is one of the more active days each season. The final two weeks, Week 15 and Week 16 also have steady afternoon declines in activity. The declines are slight. Week 16 overall probability is only slightly above 5% lower than Week 13. It was a poor assumption on my part that the Es season ends by August 15. Usually the first activity-free day does occur near or around the date, but Es activity continues until the first of September. By continuing the data collection for two additional weeks, it is noted that activity returns to levels experienced at the beginning of the season and once again becomes truly sporadic in nature.
Conclusions About 10-Meter Es Propagation:
In my 35 years of monitoring and working these phenomena, I have heard many theories as to their generation and occurrence. Some of these theories that have been proclaimed, I personally do not consider them to have any major effect of the trends shown in these charts. I strongly believe that too many have tried to figure out the wonders of Es and ignore the consistencies that it is displaying. Placing its generation of single natural and physical situations and phenomena is difficult to prove. I hoped that this 5-Year Propagation study would dispel many single-cause theories and provide mathematical, scientific, and logical answers based on consistent patterns and trends.
If Es were caused by a specific ionosphere or atmospheric events, consistency and patterns in the charts from the study would not occur. Much is still left to science to find the real cause and a mathematical approach using practical data gathering practices can show the reliability and consistency of the phenomena and dispel these types of theories.
In addition, this study was not compiled in order to predict when your specific 2, 6 or 10 Meter QTH could connect to another specific QTH. It was strictly compiled to identify the best dates, times and possible directions to work them.
Next: The Final Level of Analysis
The final analysis performed using probabilities was to compare the hour-to-hour trends of each week in the Spring/Summer Es season. With the volume and sampling, we should be able to identify where changes may occur from week to week of the season. Also, if the data accumulated was reliable, did it provide consistent and reasonable results?
Three Week Periods:
The following chart displays probabilities of working Es in 3-week segments from the beginning to the end of the season. The chart clearly details that the 6 weeks prior to and then after the Summer Solstice (12 weeks total) are the best periods for Es. The one fact that is evident is that during this 12 week period there is not much difference between them.
Weeks 1 – 4:
Week 1 (4/25-5/1) starts the Es season with some limited activity in the daytime hours. In Week 2 the best opportunity is in the late afternoon. Probabilities average less than 9% for Week 1 that on any hour a 10-Meter Es PropNET capture can occur. Probabilities almost double (over 16%) Week 2 and will favors afternoon times.
Probabilities more than double between the 2nd and 3rd weeks. Activity this 3rd week of the season clearly favors morning Es activity and typically forms a dual-diurnal pattern to be seen for other active weeks. Due to increased activity the final year of the study, the 4th week increased due to steady opportunities during the afternoon hours. Most of these weekly periods showed higher probabilities in the latter years of the study.
Weeks 5 – 8:
These are the weeks approaching the Summer Solstice. Probabilities in Week 5 increase over 8% to over 50% overall. Week 6 has the third highest probability of the Es season (near 58%) and had the highest of the season prior to the final year. The local 10 AM through 1 PM hours have probabilities of a 10-Meter PropNET capture at or above 90%.
Despite the high activity of the 6th week of the season, the 7th week (6/06) drops off over 7%. The drop off occurs during the morning hours. Week 8 returns to the level of Week 6 and has a rise in twilight activity that shows that the Summer Solstice is the peak of the season. Once again, this did not show until the latter years of the study.
Weeks 9 – 12:
Week 9 (6/20) is the week than contains the Summer Solstice. It changes little from Week 8 as there is a less than 1% increase, but the week is more morning active. There is a significant (more than 10%) decrease in Week 10, followed by a healthy resurgence of 12.6% in Week 11. This is the week that contains the Independence Day (July 4th) holiday and traditionally is known to be a very active week for Es propagation. Week 12 is unusual in that it declines in afternoon and evening activity. Most week to week declines have occurred during the morning hours.
Weeks 13 – 18:
The usual “morning decline” pattern occurs again in Week 13. Week 14 has a surge in activity is as Week 10. The sudden increase is noticeable from year to year. July 29 is usually active and is one of the more active days each season. The final two weeks, Week 15 and Week 16 also have steady afternoon declines in activity. The declines are slight. Week 16 overall probability is only slightly above 5% lower than Week 13. It was a poor assumption on my part that the Es season ends by August 15. Usually the first activity-free day does occur near or around the date, but Es activity continues until the first of September. By continuing the data collection for two additional weeks, it is noted that activity returns to levels experienced at the beginning of the season and once again becomes truly sporadic in nature.
Conclusions About 10-Meter Es Propagation:
In my 35 years of monitoring and working these phenomena, I have heard many theories as to their generation and occurrence. Some of these theories that have been proclaimed, I personally do not consider them to have any major effect of the trends shown in these charts. I strongly believe that too many have tried to figure out the wonders of Es and ignore the consistencies that it is displaying. Placing its generation of single natural and physical situations and phenomena is difficult to prove. I hoped that this 5-Year Propagation study would dispel many single-cause theories and provide mathematical, scientific, and logical answers based on consistent patterns and trends.
If Es were caused by a specific ionosphere or atmospheric events, consistency and patterns in the charts from the study would not occur. Much is still left to science to find the real cause and a mathematical approach using practical data gathering practices can show the reliability and consistency of the phenomena and dispel these types of theories.
In addition, this study was not compiled in order to predict when your specific 2, 6 or 10 Meter QTH could connect to another specific QTH. It was strictly compiled to identify the best dates, times and possible directions to work them.
Next: The Final Level of Analysis
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