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تجزیه و تحلیل وضعیت جوی در سال زراعی 93-94 /فصل دوم( دي- بهمن-اسفند)

وضعیت
موضوع بسته شده است.
A

Amir Mohsen

متخصص بخش هواشناسی
The report was made 3 hours and 21 minutes ago, at 11:00 UTC
Forecast valid from 23 at 12 UTC to 24 at 18 UTC
Wind 22 km/h from the Northwest
Visibility: 2000 m
Few clouds at a height of 914 m, Cumulonimbus.
snow rain and mist
Probability 40% :
Temporary
from 23 at 15 UTC to 23 at 24 UTC
Visibility: 0800 m
snow and fog
Becoming
from 24 at 04 UTC to 24 at 06 UTC
Wind 25 km/h from the North/Northwest with gusts up to 43 km/h
Visibility: 3000 m
Few clouds at a height of 914 m, Cumulonimbus.
Few clouds at a height of 1067 m
Overcast at a height of 2743 m
mist and snow
 
D

DR WHO

کاربر ويژه
داغ شدن سریع اتمسفر قبل از وقوع زلزله ژاپن

یک علامت هشدار؟ اتمسفر نقطه ای که زلزله 9 ریشتری 11 مارچ ژاپن در آن رخ داد قبل از رویداد آن فاجعه به سرعت گرم می شده است. دانشمندان امیدوارند که روزی از طریق اطلاعات یونیزاسیون هوا زلزله ها را پیش بینی کنند.

طبق مطالعات انجام شده اتمسفر بالای گسلی که مهیب ترین زلزله تاریخ ژاپن را تولید کرد در روزهای قبل از رخداد فاجعه به طور محسوسی گرم شده است. قبل از زلزله محتوای الکترونی یونیسفر یکی از لایه های بالایی اتمسفر به طور روشن و قابل توجهی در بالای مکان وقوع زلزله افزایش پیدا می کرده است و این مقدار در طی سه روز بعدی به اوج خود رسید و سپس زلزله اتفاق افتاد.

باور بر این است که روزهای قبل از این زلزله به سبب فشارهای وارد بر گسل های پوسته زمین در آن منطقه مقادیر زیادی گاز رادون آزاد شده باشد.



تصاویر ماهواره ای تغییرات گرمایی اتمسفر نقطه زلزله بین روزهای 1 تا 12 مارچ را نشان می دهد. محتوای کلی الکترونی در لایه یونیسفر در روزهای قبل از وقوع زلزله نیز به طور روشنی افزایش داشته است.

گاز رادیواکتیو رادون هوا را یونیزه و لذا آن را باردار می کند و از آنجایی که مولکول آب قطبی می باشد، مولکول های آب به ذره های بادار هوا جذب می شوند. اینها باعث می شود تا مولکول های آب موجود در هوا متراکم و تبدیل به مایع شوند. این فرایند با آزادشدن گرما و انرژی همراه است.

همین گرمای اضافی در اتمسفر به شکل پرتوهای اینفرارد سه روز قبل از زلزله مرگبار 9 ریشتری مشاهده گردید. ”اولین نتایج ما از اطلاعات ماهواره ای در 8 مارچ از یک افزایش سریع در تشعشعات پرتوهای اینفرارد خبر می داد.” ناسا

به خاطر اینکه ژاپن یکی از مراکز زلزله خیر دنیا می باشد در آنجا مراکز نظارتی بر اتمسفر و جو دایر شده است. در این مراکز با بهره گیری از اطلاعات ماهواره ای حالت و وضعیت اتمسفر قبل از رویداد یک زلزله اندازه گیری و بررسی می شود.



سونامی 11 مارچ که به خاطر زلزله در زیر دریا و در نزدیکی ساحل اتفاق افتاد

این عکس یک موج عظیم ناشی از این فاجعه را در حال رد شدن از خیابانی در شهر میاکو در شمال شرقی ژاپن نشان می دهد. یک “افزایش سریع” در میزان تشعشات اینفرارد اتمسفر قبل از وقوع زلزله مورد توجه قرار گرفت.



مردی در حال حرکت به سوی بندری در Kessenuma که در اثر زلزله و سونامی نابود شده است.

28 مارچ شهر میاجی.

این امیدواری وجود دارد که روزی ازتغییرات جو و اتمسفر بتوان زلزله را پیش بینی کرد.

زلزله 11 مارچ قوی ترین زلزله ای بود که تا به امروز ژاپن به خود دیده است. زلزله در زیر دریا و در نزدیکی ساحل رخ داد. نقطه مرکزی زلزله تقریبا در 43 مایلی شرق Oshika Peninsula در Tōhoku قرار داشت. تا به امروز 15 هزار نفر در اثر این فاجعه طبیعی جان باخته اند و نزدیک 10 هزار نفر ناپدید شده اند. این فاجعه کم نظیر طبیعی چند صد میلیارد دلار برای ژاپن هزینه در پی داشته است.
 
A

Amir Mohsen

متخصص بخش هواشناسی
دامنه های شمالی بینالود- امروز
چشمه قلقلی -زشک و ابتدای مسیر قله چمن

d5e6d2e9e0c167187481f7eed1a5c902.jpg
 
S

samann

کاربر ويژه
تبریک بابت برف هرچند اندک امروز و برفی که دوباره انشالله شروع میشه
و طلب عفو و مغفرت از دوستانی که از دست من رنجیدن
ارزش دوستی ها بیشتر از این برف و بارونه.. امروز تو بیمارستان در حالیکه ازدرد به خودم میپیچیدم و بیرون داشت برف میومد فهمیدم که چقد ما در اشتباهیم بالاترین نعمت سلامتیه
 
D

DR WHO

کاربر ويژه
AER scientists provide researchers and enthusiasts real-time insights on one of North America’s and Europe’s leading drivers for extreme and persistent temperature patterns. Authors Judah Cohen, Ph.D., and Jason Furtado, Ph.D., work at Atmospheric and Environmental Research (AER), a division of Verisk Climate.

Do you want to be notified when there's an update to this AO analysis? Use this form and put "AO updates" in the field labeled Requests or Comments.

January 22, 2015

Summary

A positive AO / NAO will dominate the hemispheric weather pattern over the next 10-15 days but will weaken late in the period as heights build across Alaska and into the Pacific sector of the Arctic.
Regionally, this hemispheric weather pattern will yield colder-than-normal weather for Eastern Canada and the Northeastern US with much more variable weather for much of Europe outside of Scandinavia, which should remain below normal temperature-wise. Western and parts of Central North America will see seasonable to possibly seasonably mild conditions continuing.
The stratospheric polar vortex will shift position and relocate over northern Eurasia later this week and likely remain there for 2 or 3 weeks as vertical wave propagation keeps the stratospheric circulation perturbed. This feature will reinforce much colder than normal weather for northern Eurasia.
The outlook for the AO for February favors more neutral to perhaps negative conditions developing after the first week of February as influences of the minor stratospheric warming event continue to be felt. This should allow cold weather to build back into Central Canada and the lower 48 in February. However, recent model volatility and the likely persistence of more positive NAO conditions introduce high uncertainty to this forecast.
Impacts

The near-term negative AO state across the hemisphere will quickly transition to a positive to strongly positive AO state over the next 10 days before potentially weakening to more neutral conditions thereafter. The North Atlantic Oscillation (NAO) should also remain positive to strongly positive in the near term. Much like we saw in December, model volatility in the week 2 and beyond forecasts is quite high and creates somewhat high uncertainty in the forecast for early-mid February. In terms of sensible weather, warmer to much warmer than normal weather across Western and Central North America will continue through the weekend before colder air enters Central Canada and parts of the Upper Midwest. However, troughing will remain in place across Eastern North America and keep Eastern Canada and the Northeastern US especially colder than normal. A cool to cold Western Europe / warm Eastern European pattern will weaken with time as the coldest air retreats into Scandinavia with the transition to a positive AO phase.

Meanwhile, the stratospheric polar vortex continues to slowly recover from the early January minor sudden stratospheric warming (SSW). This recovery process will also feature a re-positioning of the stratospheric polar vortex from North America over into Eurasia, which should reinforce the colder-than-normal weather regime expected across northern Eurasia. This positioning will keep the AO in the stratosphere in the negative state through the next two weeks and therefore slow the downward propagation of negative AO conditions into the troposphere.

The phase of the AO throughout February is expected to be near neutral and/or negative given the still-expected downward propagation of the SSW event. Tropospheric influences may negate the downward influence of the SSW, however, thus complicating the overall tropospheric flow pattern forecast for February. There is some confidence in persistent Western ridge – Eastern trough pattern for North America remaining in place with cold weather for the Eastern US for much of February. More uncertainty revolves around what will happen with the NAO, meaning more variable weather is likely for Europe, while northern Asia may stay cold through week 3 and possibly week 4 should the stratospheric polar vortex be slow to return to the pole..

Recent and Very Near Term Conditions

The AO will move back to the positive state after a brief time in the negative state (Figure 1), with the transition driven by the weakening of anomalously strong ridging across the Atlantic stretching into Atlantic Canada. Thus, milder air will return to Western Europe through the weekend with storminess building in the North Atlantic. The continent as a whole will see more seasonable conditions, with the coldest air shifted northward into Scandinavia. Across North America, ridging from the North Pacific will strengthen and move onshore. This feature will allow above to much above normal temperatures to continue for Western and Central North America. However, troughing will remain in place across Eastern North America and keep seasonably cool weather in place.





Figure 1. The predicted daily-mean near-surface AO from the 00Z 20 January 2015 GFS ensemble. Gray lines indicate the AO index from each individual ensemble member, with the ensemble-mean AO index given by the red line with squares.



Meanwhile, the stratospheric polar vortex is slowly recovering following the minor SSW earlier this month, as inferred by the near-neutral polar cap heights currently (Figure 2). The center of the vortex is shifting away from the North American side of the Arctic and moving across the pole (Figure 3, left). However, as discussed below, the vortex is forecasted to go through another slight displacement, which will slow its recovery.





Figure 2. Observed and predicted daily polar cap height (i.e., geopotential heights averaged poleward of 60°N) standardized anomalies. Forecast from the 00Z 20 January 2015 GFS operational model.







Figure 3. (left) 10 hPa geopotential heights (dam; contours; full field) and temperature anomalies (°C; shading) across the Northern Hemisphere at 00Z 20 January 2015. (right) The predicted 10 hPa geopotential heights and temperature anomalies from the 00Z 20 January 2015 GFS ensemble for 30 January 2015. Note that the vortex had shifted across the pole and is forecasted to be across northern Eurasia.



Near Term
1-2 week

The tropospheric AO will move quickly back to the positive AO state as the NAO also strengthens through week 1. This transition to a positive AO will be more complex than a simple poleward shift in the jet stream. Southern-stream energy in both North America and also Europe will produce rather deep troughs and potent storms in the Eastern US (with phasing) and the Mediterranean region (more of a cutoff system) (Figure 4, left). These storms will produce cold air dynamically and undercut the larger-scale temperature changes expected in the near term with the transitioning AO. Thus, we continue to favor colder-than-normal weather for week 1 for the Eastern US and the Mediterranean countries.





Figure 4. (left) 500 hPa forecasted geopotential heights (dam; contours) and anomalies (m; shading) for 26 January 2015. Though the AO is transitioning to a positive phase, split-flow in the jet stream is responsible for two large-amplitude features: (1) A phased storm system across the Eastern US and (2) A southern stream low moving through the Mediterranean. Both of these features will keep colder than normal weather in those regions. (right) 500 hPa forecasted mean geopotential heights (dam; contours) and anomalies (m; shading) from 31 January to 4 February 2015. Note the persistent positive NAO conditions, the persistent low over Baffin Bay, and the building ridge across the Bering Strait. All forecasts from the 0Z 20 January 2015 GFS ensemble.



The strongly positive AO will continue into week 2 but may weaken thereafter (Figure 1) in response to two key features: (1) a slight weakening trend in the NAO as low pressure moves out of Iceland and into the Baltic Sea; and (2) a building ridge across the Bering Strait and extending into the polar regions (Figure 4, right). Concomitant with this change will also be a shift in the stratospheric polar vortex towards the Siberian coast (Figure 3, right), reinforcing the cold surface temperatures expected across Eurasia over the next two weeks. This, combined with the resumption of vertical wave propagation during the period (Figure 5) because of the favorable ridge-trough pattern across Asia will slow the recovery of the stratospheric polar vortex. The GFS operational and ensemble-mean hint at low polar cap heights returning very late in the period (Figure 2), but the expected shift in the polar vortex off of the pole may slow this process.





Figure 5. Observed and predicted daily vertical component of the wave activity flux (WAFz) standardized anomalies, averaged poleward of 40-80°N. Forecast from the 00Z 20 January 2014 GFS operational model.



Cold weather will remain in place over Scandinavia with seasonable weather for the remainder of Europe expected. Other than Eurasia, the coldest weather (anomaly-wise) hemispherically will be across Eastern Canada and the Northeastern US in association with the other piece of the tropospheric polar vortex centered across northern Hudson Bay (Figure 4, right). Colder weather may also seep into the Upper Plains and Upper Midwest as well. However, continued ridging in the Western US will spread through the Central Plains and keep seasonable to seasonably mild weather in place in those regions.

3-4 week

Both the GFS and the ECMWF ensemble-means (not shown) suggest a more neutral AO state at the end of week 2 and entering week 3. This change in the AO has support from the expected tropospheric pattern forecasted at the end of week 2 (Figure 4, right), the idea of downward propagation from the minor SSW in early January, and the anticipation of weak Phase 6-7 of the MJO expected (see below). The key to a more certain (and persistent) negative state of the AO will be a breakdown of the positive NAO thus far. Competing influences between the stratosphere and troposphere are preventing the NAO from flipping to the negative state more permanently, however. Hence, while much of North Central Asia and Scandinavia will remain cold, Europe could remain more seasonable through the period, much as it has been for December and early January. Meanwhile, ridging in the Pacific should continue to hold into this period, reinforced both by upstream troughing in Eastern Asia and potentially from tropical forcing. The downstream response for North America will be maintenance of the Western ridge – Eastern trough pattern, though the Eastern trough may broaden, delivering colder-than-normal weather into parts of the Central and Eastern US and Canada.

Longer Term
30–day

Unlike December and January, we anticipate that the AO will be more neutral or negative than positive through mid-late February. As stated above, the key to a strongly negative AO will be a more permanent reversal of the NAO. The long-range models do not favor such a reversal because of the persistence of a piece of the tropospheric polar vortex near Baffin Bay. This tropospheric polar vortex feature appears to be a near-direct reflection of the “split” in the stratospheric polar vortex that occurred in early January. If this feature remains in place, anomalous ridging will be difficult to build into Greenland, and hence the NAO will remain positive. Nevertheless, the downward influence of the minor SSW should be enough to keep the AO neutral or weakly negative in our view. For North America, the persistent vortex should favor colder than normal weather across Central and Eastern Canada and the United States. More variable weather is expected for Europe given slightly positive NAO state possible.

Winter AO Outlook
Arctic Sea Ice

Arctic sea ice extent continues to run below normal primarily in the Pacific sector (Figure 6) with above-normal conditions seen off of Northeastern North America. The below-normal sea ice in the Pacific has also been associated with warmer waters across the North Pacific in conjunction with a rather positive Pacific Decadal Oscillation (Figure 7). Ridging expected over the next two weeks in the Pacific sector should work to keep the Bering Strait low sea ice anomaly in place. Meanwhile, sea ice over the Barents-Kara Seas is on average normal and should remain as such as colder air settles into Northern Europe and Asia.




Figure 6. Observed Arctic sea ice extent on 19 January 2015 (white). Orange line shows climatological extent of sea ice based on the years 1981-2010. Image courtesy of National Snow and Ice Data Center (NSIDC).



El Niño/Southern Oscillation and the Pacific Basin

Weak Central Pacific El Niño conditions persist with warm anomalies centered near the Dateline and weekly NINO-3.4 and NINO-4 indices still at +0.5-0.9°C (Figure 7). The North Pacific continues to show a fairly strong positive PDO pattern in the ocean into January – note that the PDO index set a record high for December (+2.51 standard deviations). In terms of tropical convection, the MJO is currently exiting Phase 7 and turning neutral (i.e., the center of the MJO phase diagram; Figure 8). Both the GFS and ECMWF show that weak convection may reappear near the Maritime Continent and the Western Pacific Warm Pool (Phases 5-6). Given the spread in the ensemble members (i.e., yellow tracks in Figure 8), we feel the influence of the MJO on the AO into February could be weak, but it will require monitoring.



Figure 7. The latest weekly global SST anomalies (ending 17 January 2015). Image courtesy of NOAA/ESRL/PSD.





Figure 8. Past and forecast values of the MJO index. Forecast values from the 00Z 20 January 2015 ECMWF model. Sector numbers indicate the phase of the MJO, with geographical labels indicating where anomalous convection occurs during that phase Image source: Phase Diagrams for MJO Tracking



Northern Hemisphere Snow Cover

Hemispheric snow cover has decreased over the last week thanks to warmups in Western and Central North America as well as Eastern Europe (Figure 9). In the near-term, snow cover will likely remain somewhat steady as expected gains in certain regions (e.g., the Eastern US) may be negated by further losses elsewhere (e.g., the Central US). Any buildup of snow for the Eastern US, however, will assist in further developing colder-than-normal weather for the region expected over the next 2-3 weeks. Snow cover may also advance temporarily in Eastern Europe with storminess in the Mediterranean, but more mild weather expected to take hold during week 2 and 3 would work against further advance.





Figure 9. Observed Northern Hemisphere (top) and North American (bottom) snow cover extent through 5 January 2015 for this season (red curve) and the past 9 seasons (other colored curves). Image source: Plots of snow extent derived from satellite-based snow cover map products



Quasi Biennial Oscillation (QBO)

The easterly QBO signature continues to mature at 50 hPa, having peaked at 30 hPa last month. Westerly winds have already appeared at 10 hPa and are descending slowing through the tropical stratosphere. Nevertheless, wave energy continues to be anomalously directed toward the polar stratosphere because of the easterly winds near the tropopause.



Temperature Anomaly Animation

Below we show the daily temperature difference between those with observed high October Eurasian snow cover minus low October Eurasian snow cover from September 1 through February 28 in degrees Celsius. Temperature differences are shown in shading and those differences that are found to be statistically significant are outlined by a black contour. This is not meant to be a forecast but instead shows the general progression of the temperature anomalies across the Northern Hemisphere based on October Eurasian snow cover variability alone.
 
A

Amir Mohsen

متخصص بخش هواشناسی
samann گفت:
تبریک بابت برف هرچند اندک امروز و برفی که دوباره انشالله شروع میشه
و طلب عفو و مغفرت از دوستانی که از دست من رنجیدن
ارزش دوستی ها بیشتر از این برف و بارونه.. امروز تو بیمارستان در حالیکه ازدرد به خودم میپیچیدم و بیرون داشت برف میومد فهمیدم که چقد ما در اشتباهیم بالاترین نعمت سلامتیه
کلیک کنید تا باز شود...
درود سامان عزیز
از صمیم قلب برای شما و همه دوستان خوبم آرزوی صحت و سلامتی دارم.
امیدوارم که کسالت ها هر چه زودتر برطرف بشه و همیشه شاد باشید.
 
S

samann

کاربر ويژه
Amir Mohsen گفت:

درود سامان عزیز
از صمیم قلب برای شما و همه دوستان خوبم آرزوی صحت و سلامتی دارم.
امیدوارم که کسالت ها هر چه زودتر برطرف بشه و همیشه شاد باشید.
کلیک کنید تا باز شود...
مرسی محسن عزیز. فعلا حالا حالاها خونه نشین شدم .
شما واقعا انسان بزرگواری هستین . انشالله همیشه موفق و سلامت باشین .
بودن شما در این جمع قوت قلبه همه ماست :گل:
 
A

Amir Mohsen

متخصص بخش هواشناسی
با آرزوی بهبود سریع سامان عزیز و تشکر از لطف و محبتش.
آسمان بتدریج از سمت شرق ابری شده و در این لحظه کریستالهای برف در منطقه ما زیر نور روشنایی معابر قابل مشاهده است.
در محورهای خراسان شمالی و همچنین بعضی از محورهای کوهستانی خراسان رضوی رگبار همرفتی برف رخ داده که در گردنه اسدلی هم برف سنگینی باریده و همچنان ادامه داره
 
ن

نیما 68

کاربر ويژه
samann گفت:
تبریک بابت برف هرچند اندک امروز و برفی که دوباره انشالله شروع میشه
و طلب عفو و مغفرت از دوستانی که از دست من رنجیدن
ارزش دوستی ها بیشتر از این برف و بارونه.. امروز تو بیمارستان در حالیکه ازدرد به خودم میپیچیدم و بیرون داشت برف میومد فهمیدم که چقد ما در اشتباهیم بالاترین نعمت سلامتیه
کلیک کنید تا باز شود...
سامان جان امیدوارم هر چه سریعتر سلامتی کاملاتو بدست بیاری :گل:
 
A

Ahmad7777

New member
samann گفت:
تبریک بابت برف هرچند اندک امروز و برفی که دوباره انشالله شروع میشه
و طلب عفو و مغفرت از دوستانی که از دست من رنجیدن
ارزش دوستی ها بیشتر از این برف و بارونه.. امروز تو بیمارستان در حالیکه ازدرد به خودم میپیچیدم و بیرون داشت برف میومد فهمیدم که چقد ما در اشتباهیم بالاترین نعمت سلامتیه
کلیک کنید تا باز شود...


سامان جان انشالله بهتر بشی و بیشتر از قبل در انجمن فعالیت مفید داشته باشی.ما به اطلاعات استادانی همچون شما و آقا امیرمحسن و......نیاز داریم.:گل::گل:
 
H

heaven1

مدیر بخش هواشناسی
وقتي سيل يخ ميزند

تصاویر زیر ماشین هایی را نشان می دهد که در آب یخ زده گرفتار شده اند. ظاهرا این یخبندان پس از وقوع سیل در منطقه ای بنام دودینکا در روسیه اتفاق افتاده است.

uyhrkmt02o1rszq03gs.jpg

552iq0jiz3cvglhflrh.jpg
 
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