Http://met.no/english/topics/nomek_2005/ http://www.comet.ucar.edu/ The sources for meteorological information… worldwide… http://meted.ucar.edu/norlat.php.

http://met.no/english/topics/nomek_2005/ http://www.comet.ucar.edu/
The sources for meteorological information… worldwide…

… Meteorology … an Art and a Science
Phil the Forecaster Chadwick The Meteorological Service of Canada Warning - This is the first time (December 2004) for this presentation. I rarely give the same presentation twice… this is either due to forgetting stuff or adding stuff. The humour is mainly “off-the-cuff”. All of this information is available on the Web. No special software or tolls are required. The theme of this presentation is that meteorology is an art as well as a science. Humans have a skill set that is still indispensable to solving the earth and atmospheric puzzle. Using the human skill set and a tool belt of conceptual models, the human role in analysis and diagnosis is absolutely critical. Without the understanding that results from analysis and diagnosis, the human is quite incapable of making consistent, reasonable and value added improvements on the NWP. At this point, the proposed man-machine mix deteriorates from the envisioned Professional-Machine Symbiotic relationship into a Mechanic-Machine Servitude. The best meteorologists thrive on analysis and diagnosis to feed their passion for understanding how the earth-atmosphere system really works. With this knowledge, they can then continue to make significant improvements on the models. Finally, to quote Cyndi Lauper, “Meteorologists just want to have fun”.

#0177 "Rideau Deformation Zone"

#0594 "Deformation"

The Forecaster’s Friend
NOMEK April 2005

Analysis and Diagnosis
What is this telling us? Basically everything… but you have to know how to decipher it. This satellite image is from the first case study of October 19th, 2004. Analysis and Diagnosis Using All Data Sources and Conceptual Models This encapsulates some of the operational efforts of the past two decades. Meteorological Prediction can be simplified into edge prediction which can be interpreted in terms of meteorological processes. This presentation is also about the analysis and diagnosis of edges. What do they mean and where will they be in the future.

Tempest in a Horse Trough
X X X Take a horse trough with a skim of spruce pollen on top; Add a jet maximum with a swish of your hand; Analyze and marvel at the swirls that result. It is similar in the real atmosphere. N

Looking Upward at the deformation zone
The satellite is reality. We can even view the features from the ground. This is the view from my front yard looking east… and up!

The Deformation Zone: Shape
Season: All Year Phenomena: Air Mass and Circulation Sheaths Tools: GOES water vapor Forecast Challenges: Locate the axis of maximum winds Identify and predict the shortwave troughs and jet maxima in order to predict the location of the lift and energy conversions Identify Comma and Anticomma patterns Identify paired vorticity centers Identify Conveyor Belts The COMET Toolbox Approach… Page title: The Deformation Zone: Shape s01p01 image spec splash_sat.gif 400x320 description: sexy pic of the deformation zone (use a water vapour imagery from this or a similar case instead of the 10.7 um) copyrights: most likely NOAA notes: use an image from the loop we’ll be using and crop/enhance to focus it on the deformation zone Narration: Go with the flow… The deformation zone should be your best friend. It is very predictable and is the balance between opposing circulations. The deformation zone is actually a sheath or skin on an air mass circulation. Potential temperature can be used to identify the air mass and thus the deformation zone. Distortions in the deformation zone sheath in the vertical can thus be related to instability. In this Satellite Toolkit, you’ll be asked to identify the main features associated with the deformation zone. This includes the Col, the axis of dilatation and the axis of contraction.

DZ Satellite Signature – Conceptual Model
Deformation Zone pattern with a Col or Saddle Point in the Circulation Confluent Asymptotes along the axis of dilatation Pairs of vorticity maxima and vorticity minima Pairs of Commas and Anticommas These are the component parts of the dynamic feature or conceptual model.

Key Features of the Deformation Zone
X N Page title: Key Features of the Deformation Zone s01p02 Note: Animation should show the stretching that occurs along the deformation zone. The col could be dropped on as it animates with the axes of dilatation. Note: Feature identification tool set will be an interactive feature for dragging and dropping icons and for drawing lines in various colors. We’ll have to see if we want it to work on each image in the loop or if it is only available on the last image (easier to program). image spec: sat_loop_2004_05_04.swf label: GOES µm IR and WV 0015-XXXX UTC 04 May 2004 Note: use standard looper but add feature identification tools Narration: The shape of a deformation zone can reveal much about the vorticity centres generating the pattern. The deformation zone is a very predictable feature that is the balance between opposing circulations. Minor errors in the NWP prediction of these circulations do not have large impacts in the location or shape of the deformation zone. If the NWP deformation zone is dramatically different from that in the actual atmosphere, the implication is that the NWP is dramatically in error. In either case, the information provided by the deformation zone is vital to the successful prediction of the atmosphere. Since the deformation zone is the result of opposing flows, it can be diagnosed from the perspective of either circulation and either conveyor belt. The result will be the same. The following concepts can be applied at any scale of the atmosphere. The accompanying examples illustrate the principles on the larger scale and do not attempt to delve into the small scale features. If one examines the illustrative examples closely, one will find devils in the detail. To diagnose the devilish details one must apply the same concepts at smaller and smaller scale. The concepts still apply but the details are glossed over when examining the large scale circulations. To summarize, there are literally hundreds of deformation zones in every satellite image if one diagnoses all scales of the atmosphere. Here we focus on the scale that best illustrates the concepts. There are lots of features associated with this set up. Take a crack at identifying some of them. Specifically, use the feature identification tools to drag and drop the symbols onto the XXXX UTC image. When your finished, click the Done button to see how well you’ve identified the key features. Dry Surge

Deformation Zone Conceptual Model
X COL Deformation Zone Points… Find the Col – or identify diverging streamlines. Both approaches will locate the central portion and col of the deformation zone. Go upstream and downstream from the col… never crossing the streams… that’s a bad thing – just ask the Ghostbusters. Possible great Easter egg here. I have the wave file already for don’t cross the streams… Continue both upstream and downstream until the flow stops converging. Place an arrow head at both ends and call it a deformation zone. The deformation zone should be your best friend. It is very predictable and is the balance between circulations. The strength of the circulations themselves may even be poorly handled by the NWP but this will not have large impacts on the placement of the associated deformation zones in the numerical atmosphere. Discrepancies between the satellite and numerical atmosphere deformation zones will only be noted when the vorticity centres are not placed correctly in the NWP. In this way, the deformation zone is the best tool for diagnosing model behaviour. The deformation zone is actually a sheath or skin on an air mass circulation. Potential temperature can be used to identify the air mass and thus the deformation zone. Distortions in the deformation zone sheath in the vertical can thus be related to instability. It is important to think of the vorticity centres as something more that just dynamic features to locate vorticity advection. More importantly, they control the circulation of the air mass in its vicinity. In essence, the vorticity centre controls the location of the associated deformation zone, air masses and associated conveyor belts. By doing this it controls the location of important meteorological quantities that are essential for an accurate diagnosis and prediction of the atmosphere. BY scale analysis we know that quasi horizontal motions are orders of magnitude larger that vertical motions in the atmosphere. This is justification for drawing deformation zones on quasi horizontal surfaces like isobaric charts. Thus the concept of deformation sheaths although vital in order to get an appreciation of the three and maybe even four dimensional aspects of atmospheric circulations, can be simplified by examining two dimensional deformation zones. X N

DZ Shape Forecast Challenges
Identify and predict the location, orientation and shape of the deformation zone Relate this information to the vorticity center intensity as well as the curvature of the related axis of maximum wind and the strength of the related wind maxima Part of this is the challenge to correctly identify the feature. The other part is using the information to improve the prediction. Basically on all of these, one can say that the NWP is often incorrect and can be improved by analysis of the actual atmosphere through the use of satellite imagery. Should we be highlighting the characteristic model errors?

Circulation Centre and Relative Intensity from the Deformation Zone
X X N The relative strength of the circulations creating a deformation zone can be deduced from the shape of the deformation zone. Remember to think in the relative and not the absolute frame of reference atmosphere. This is the simplest case with a nearly straight deformation zone. The circulations around each vorticity center is the same. Therefore the relative wind flow around each is the same. The size of the symbol is used to denote this relative strength. If one introduces a wind maximum in either confluent asymptote, the vorticity center pairs on either side of the wind maximum will increase in magnitude by the same amount. This is illustrated in the second (lower) graphic where the purple line indicated the axis of maximum winds and the oval is the location of the associated wind maxima. X N N X

X N X The relative strength of the circulation centers can be diagnosed by the shape of the deformation zone. The size of the symbol is used to denote this relative strength. The change in the magnitude of the vorticity centers is due simply to curvature. If one introduces a wind maximum in either confluent asymptote, the vorticity center pairs on either side of the wind maximum will increase in magnitude by the same amount. This is the typical pattern seen in the atmosphere associated with low pressure area to the west (left) and a high pressure area to the east (right).

X The relative strength of the circulation centers can be diagnosed by the shape of the deformation zone. The size of the simple is used to denote this relative strength. This is the typical pattern seen in the atmosphere associated with a high to the west (left) and a low pressure area to the east (right). The possible shapes of deformation zones is endless. Humour – distort a clown face to the smiling symbols… X N

Quick Deformation Zone Analysis
The Common Bozo the Clown Pattern Very divergent, strong northerly flow pattern N X In the Bozo the Clown Pattern (I am sorry to take full responsibility), a strong northerly jet maximum drops into a preexisting, strong curved upper trof. The wind maximum also carries a strong vorticity minimum. The result is that the deformation zone is curved like a happy face. Basically I am just making this up so that it fits Bozo. However, the pattern is quite real. The vorticity centres on the south side of this deformation zone are weaker as a result of the curvature considerations. X N

Straight Deformation Zone
X N N X In the broad sense, this fits the straight deformation zone conceptual model. Of course there are devils in the details in one looks at the smaller scale which clearly must be evident since this is a large deformation zone. The main point to illustrate is that these vorticity centres are all about the same in intensity. Note to Bruce… animation would allow better placement of the vorticity centres. There might be people out there who argue about where I slapped them down. I did so because I don’t have the loops and I want to illustrate the principles. Sue me! (humour intended)

Convex Deformation Zone
Ditto but I repeat the caveat anyway. Note to Bruce… animation would allow better placement of the vorticity centres. There might be people out there who argue about where I slapped them down. I did so because I don’t have the loops and I want to illustrate the principles. Sue me! (humour intended)

Convex Deformation Zone
Once again I have focused on the large scale and ignored the many small scale features wherein the devil hides.

Concave Deformation Zone
X N N X There are literally hundreds of deformation zones in every satellite image if one diagnoses all scales of the atmosphere. Here we focus on the scale that best illustrates the concepts. Bozo the Clown Deformation

X N N X A real Bozo the Clown pattern.. Complete with a protruding nose. Do you see it?

X X N It is important to stay within the same circulations at a given scale when one is diagnosing a single deformation zone. Animation is best used to identify separate circulations.

Quick Tricks to DZ Analysis
From D to Z…

The Double Vorticity Maximum Pattern Analyzing any two of the features yields the best estimate of the third. The vorticity minima can always be inferred. X N 4 3 When the vorticity maxima dominate the streamline (vorticity) pattern, the result is what I refer to as the double vorticity maxima pattern. Actually these double vorticity patterns can be strung together indefinitely as would be the case along a channeled axis of maximum winds. When two neighbouring vorticity maximum centers (1 and 4 in the above graphic) are identified along the same axis of maximum winds, the associated deformation zone can be quickly sketched between them. It becomes a reflex act of analysis with practice. The relatively weak vorticity minima (2 and 3 in the above graphic) can always be inferred. They are weak because speed shear is the only generating force for their existence since the associated curvature is definitely cyclonic in this circulation. Vorticity minimum (2 in the above graphic) is more likely to be stronger than the more western vorticity minimum (3 in the above graphic) as a result of the stronger winds which are likely east of the col. The probable axis of maximum winds is sketched in purple with the open ovals indicating probable wind maxima. With practice the deformation zone between neighbouring vorticity maxima can be analyzed quickly and accurately. The analysis of any two if the three features (the two vorticity maxima and the deformation zone) quickly yields the best estimate of the third feature even if it is weak and not obvious. This relies on the wave nature of atmosphere flows whereby subtle vorticity centers can be inferred from neighbouring vorticity centers that are better defined. X N 1 2

X The Double Vorticity Maximum Pattern – Strung together N X N X Analyzing any two yields the best estimate of the third. The vorticity minima can always be inferred. N X The double vorticity maxima pattern can be strung together indefinitely as would be the case along a channeled axis of maximum winds. The probable axis of maximum winds is sketched in purple with the open ovals indicating probable wind maxima. This is an example of a southwesterly channeled jet where the jet maxima and associated short wave trough and associated vorticity maxima have a very short wavelength. The associated vorticity advection field merges together into a vorticity maximum lobe. The individual nature of the vorticity advection fields only become discrete when the wavelength of the short wave pattern increases. The above pattern is quite common in northwesterly channeled jets east of an upper ridge where the wavelength of the short waves is typically short. The pattern is also common in southwesterly upper jets east of an upper trough but the wavelength tends to be longer than that associated with the northwesterly channeled jet. N X This is a southwesterly Channeled jet pattern. A northwesterly channeled jet is more common.

X The Double Vorticity Maximum Pattern – Strung together N X N X N X This illustrates how subtle or missing vorticity centers or cloud features can be inferred using the wavelength characteristics of the atmosphere. The previous three slides can be redone from a satellite perspective by simply replacing the deformation zone and vorticity center conceptual model of the comma with the moisture representation of the comma. N X

The Double Vorticity Minimum Pattern Analyzing any two of the features yields the best estimate of the third. The vorticity maxima can always be inferred. X N 4 3 N Note that I constructed this pattern by simply changing the relative intensities of the vorticity minima and vorticity maxima and resizing the text to correspond. This changes the entire shape of the associated deformation zone. When the vorticity minima dominate the streamline (vorticity) pattern, the result is what I refer to as the double vorticity minima pattern. Actually these double vorticity minima patterns can be strung together indefinitely but the pattern is rare. When two neighbouring vorticity minimum centers (2 and 3 in the above graphic) are identified along the same axis of maximum winds, the associated deformation zone can be quickly sketched between them. It becomes a reflex act of analysis with practice. The relatively weak vorticity maxima (1 and 4 in the above graphic) can always be inferred. They are weak because speed shear is the only generating force for their existence since the associated curvature is definitely anticyclonic in this circulation. Vorticity maxima (4 in the above graphic) is more likely to be stronger than the more western vorticity maxima (1 in the above graphic) as a result of the stronger winds which are likely east of the col. In fact vorticity maxima 1 in the graphic may be so weak as to be non-existent. The probable axis of maximum winds is sketched in purple with the open oval indicating probable wind maximum. With practice the deformation zone between neighbouring vorticity minima can be analyzed quickly and accurately. The analysis of any two if the three features (the two vorticity maxima and the deformation zone) quickly yields the best estimate of the third feature even if it is weak and not obvious. This relies on the wave nature of atmosphere flows whereby subtle vorticity centers can be inferred from neighbouring vorticity centers that are better defined. X 1 2

The Double Vorticity Minimum Pattern – Strung together Analyzing any two yields the best estimate of the third. The vorticity maxima can always be inferred. N X N X N X N X This is a northwesterly channeled jet pattern which is quite common. The double vorticity minima pattern can be strung together indefinitely as would be the case along a channeled axis of maximum winds. The probable axis of maximum winds is sketched in purple with the open ovals indicating probable wind maxima. This is an example of a northwesterly channeled jet where the jet minima and associated short wave ridges and associated vorticity minima have a very short wavelength. The associated vorticity advection field merges together into a vorticity minimum lobe. The individual nature of the vorticity advection fields only become discrete when the wavelength of the short wave pattern increases. The above pattern is quite common in northwesterly channeled jets east of an upper ridge where the wavelength of the short waves is typically short. The pattern is also common in southwesterly upper jets east of an upper trough but the wavelength tends to be longer than that associated with the northwesterly channeled jet. N X The Vorticity Maxima deformation zones can also be added into the conceptual model.

The Associated Moisture Pattern with a Northwesterly Channeled Jet
X The Vorticity Maxima Comma Cloud Pattern The double vorticity minima pattern can be strung together indefinitely as would be the case along a channeled axis of maximum winds. The probable axis of maximum winds is sketched in purple with the open ovals indicating probable wind maxima. This is an example of a northwesterly channeled jet where the jet minima and associated short wave ridges and associated vorticity minima have a very short wavelength. The associated vorticity advection field merges together into a vorticity minimum lobe. The individual nature of the vorticity advection fields only become discrete when the wavelength of the short wave pattern increases. The above pattern is quite common in northwesterly channeled jets east of an upper ridge where the wavelength of the short waves is typically short. The pattern is also common in southwesterly upper jets east of an upper trough but the wavelength tends to be longer than that associated with the northwesterly channeled jet. The Vorticity Minima Anticomma Cloud Pattern

Typical DZ Applications

Deformation Zone Exercise
W to E System DZ with N to S Def Zone Upstream… Main Jet splits. A significant amount of energy goes to the north… and a significant amount goes south. Slow moving system. Freezing Rain pattern X N N X X N Two illustrations of the application of classic dynamic meteorology using the deformation zone, follow. A Deformation Zone is the best forecast tool available. Identified best in streamline space, they are the outer edges or boundaries of atmospheric swirls. Their positioning, shape and orientation is determined mainly by the location of the swirls and then by the intensity of the swirls. As a result these boundaries are relatively insensitive to minor NWP errors in vorticity intensity. The predicted deformation zones are thus as accurate as the placement of the vorticity centers in the numerical atmosphere and can be used with some confidence. The shape and orientation of deformation zones can tell you much about the location and relative strength of the circulation centers. The first image to the left reveals a northeast to southwest deformation zone. The portion of the deformation zone to the left of the col is strongly curved indicating a strong vorticity maximum due mainly to curvature. The deformation zone to the right of the col is strongly curved anticyclonically indicating a strong vorticity minimum due mainly to curvature. There will be significant decent downstream from this vorticity minimum. The orientation of the upper trough by identifying and joining the cyclonic toughs in the upper jets, is clearly northwest to southeast. This implies a southward transport of westerly momentum with the result that the strong vorticity maximum will continue to spin. Identification of short wave troughs in this digging upper flow will aid in the identification and timing of any changes in system intensity. The final diagnosis with respect to this system is that it will translate eastward with the digging upper trough. The atmosphere relative motion of the system should be northeasterly given the orientation of the downstream portion of the deformation zone. However the trough and atmospheric flow is digging southeastward. The vector addition of the motion relative to the atmospheric flow and the motion of the atmospheric flow itself, should result in an earth frame of reference motion that is generally to the east. The second image to the right is drawn with the cloud boundary west of the north to south upper level deformation zone. This deformation zone denotes the leading edge of the next short wave. The cloud comma west of the north to south deformation zone is mainly south of the col and is the signature for the short wave and the associated wind maximum which is generating it through shear vorticity. The northern extent of this deformation zone reveals that either the vorticity minimum downstream is very strong or the vorticity maximum with the comma cloud is very strong or both are strong. In other words, a significant portion of wind energy is being directed northward up and around an upper ridge. The bottom line is that the north to south orientation of this deformation zone signifies and split in the upper flow. This wind maximum in the southern stream will energize the southern vorticity maximum or spin it up as it moves slowly eastward. If this wind maximum is strong enough it could result in the split cold frontal pattern for the associated fronts. This would have implications for convection. Note that the downstream half of the deformation zone marks the location of the downstream axis of maximum winds. To a good approximation, this axis of maximum winds is also the direction in which the system will travel. If the system is intensifying, expect it to steer to the left of this axis and to lower atmospheric heights. If the system is weakening, it will follow this axis or even steer slightly to the right and toward higher atmospheric heights as the central pressure fills. X NE to SW System DZ…. Main Jet plunges south of the cloud pattern. A single upper trof and a cloud system that will translate. Note that the flow is not split. N X N

Moisture Patterns to Features
X N X N The moisture patterns can be diagnosed to identify and locate the dynamic features. Starting with the moisture patterns, one can locate in preferred order, the axis of maximum winds, jet maxima, vorticity maxima, vorticity minima and deformation zones. These dynamic features can then be related to the corresponding numerical analysis of the same dynamic features. The easiest discrepancies to note are the misplacement or absence of vorticity centers in the numerical atmosphere. Misplacement of vorticity centers not only changes the center of cloud rotation but also shift the associated axis of maximum winds as well.

Features to Moisture Patterns
X N X N The dynamic features can be diagnosed to identify and locate the moisture patterns. Starting with the numerical atmosphere, one can locate in preferred order, the axis of maximum winds, jet maxima, vorticity maxima, vorticity minima and deformation zones. Moisture patterns can then be constructed from these dynamic features using the conceptual models of the comma, the anti-comma, conveyor belts and the deformation zone. These moisture patterns can be diagnosed from any numerical atmosphere at any prediction time period and then compared to the corresponding actual satellite derived moisture pattern when it becomes available. This comparison can be used to note discrepancies in the misplacement or absence of vorticity centers in the numerical atmosphere. Misplacement of vorticity centers not only changes the center of cloud rotation but also shift the associated axis of maximum winds as well. To summarize, dynamic features and moisture patterns are interchangeable. They are the same thing.

All Kinds of Deformation Zones
X X X X X N X N X N X There are even more details depending on the scale you are interested in… and are required to solve your forecast concern.

Using Human Artistic Strengths
Analyze and Diagnose the REAL Atmosphere first Use all of the Conceptual Models in your Tool belt Analyze and Diagnose the Numerical Atmosphere second Focus and Zoom in from the Largest Scale into your Scale Fix what needs fixing… Remember to keep your sense of humour and have FUN, Fun, fun! Meteorology is more than numbers… it is an art Orphan Annie or maybe it was Anne of Green Gables said, “Tomorrow is a new day with no mistakes in it”. If you are really doing the science, the only day you will not make a mistake as a meteorologist is the day you don’t go into work. The Deformation Zone example is just one of about 30 tools/conceptual models planned for completion by COMET and placed on the WEB for use by anyone.

Questions? #0635 "Flash Flood"
Alternate ending depending on the group. #0635 "Flash Flood"

Questions? Margarita ville Goodbye Cruel World…
Off To See the Deformation Zone Margarita ville

Http://met.no/english/topics/nomek_2005/ http://www.comet.ucar.edu/ The sources for meteorological information… worldwide… http://meted.ucar.edu/norlat.php.

Similar presentations

Presentation on theme: "Http://met.no/english/topics/nomek_2005/ http://www.comet.ucar.edu/ The sources for meteorological information… worldwide… http://meted.ucar.edu/norlat.php."— Presentation transcript:

Similar presentations

About project

Feedback

Log in

Auth with social network:

Http://met.no/english/topics/nomek_2005/ http://www.comet.ucar.edu/ The sources for meteorological information… worldwide… http://meted.ucar.edu/norlat.php.

Similar presentations

Presentation on theme: "Http://met.no/english/topics/nomek_2005/ http://www.comet.ucar.edu/ The sources for meteorological information… worldwide… http://meted.ucar.edu/norlat.php."— Presentation transcript:

Similar presentations

About project

Feedback