Name:______Project#4

Synoptic Meteorology I Due: Thursday, 20 September 2018

Part I (Group Portion),teammate initials: ______

{by initialing above you are acknowledging that you participated in research, discussion, and analysis that went into the responses to Part I}

Atmospheric Oscillations

In all the GARP exercisesfor this project you will be using the “GFS thinned”model forecast initialized at 1200 UTC 07January 2014. Plot lat/lonevery five degrees.

[1]Go to the web site to determine the NAO index for 9 January 2014 and write the index value below. Make a note of the type of sea level pressure (e.g. stronger-than-normal high pressure) you’d expect to find near Iceland and near the Azoresin the subtropics given the phase of the retrieved NAO index.Confirm or refute if this is what is foundon the GARP 0000 UTC 10January 2014 (F60)SLPforecastmap. Why might there be a difficulty between interpreting the NAO index and what you observe on the GFS SLP analysis? In other words, have you been given enough information to make such a confirmation? If not, what other field(s) would you need?

[2]Create a table listing using the GARP 500 hPa geopotential height values at the four PNA index locationsfor two forecast periods (00-h fcstand72-h fcst). Assume the time mean of the 500 hPa geopotential height values to be 5820, 5380, 5320, and 5760 meters at ~Hawaii, E. Pacific, W. Canada, and SE U.S., respectively. Calculate the PNA index for the two forecast periods. Describe the “classic” high PNA index 500 hPa pattern and determinewhichof the two 500 hPageopotential height forecasts(if any) most closely matches the classichigh PNA pattern.

[3] Go to the web site click on “Archive of MJO indices (1978-present).” at the bottom of the web page and choose “2005” to look at the MJO index plot for calendar year 2005. Describe what you find at 120oE at the end of December on this plot. Determine if the end of December 2005 (leading into early January 2006) indicates the presence of MJO-induced enhanced convection and the potential for interactionbetween theMJO-induced convection in the western Pacific orIndian Ocean and the weather patterns of the west coast of the U.S.

[4]Go to click on the “30 hPa zonal wind (m/s) JPEG” plot. Note below the sign (“+” or “”of the QBO index from the plot during Jan 1993 and Jan1994 and then go to the Univ. of Wyoming upper air web site and retrieve the Singapore [WSSS (48698)] soundings for 0000 UTC 15Jan 1993 and 1994. Note the differences in the winds above the 30 hPa level and determine which sounding is most similar to the QBO schematic within the 10 - 30 hPa layer found on slide#33 of LP#3.

Name:______Project#4

Synoptic Meteorology I Due: Thursday, 20 September 2018

Part II (Individual Portion):

[1] A gradual rise in sea-level causes a slight increase in the area of the earth’s surface covered by “smooth” water, compared to “rough” land. Explain the impact of decreased surface friction on the mean meridional circulations and eddies (standing waves and transients together) recalling that global atmospheric motions are constrained to conserve zonal momentum over a year. Note: In order to receive full credit on this problem, you must apply Eq. (1.24) from lecture packet#2 in your discussion. Draw diagrams if this helps to make your case.