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Synoptic Met II => Final Exam > Extended Forecasting (Atmospheric Oscillations) > Flashcards

Extended Forecasting (Atmospheric Oscillations) Flashcards

1
Q

What does MJO stand for?

A

Madden-Julian Oscillation

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2
Q

The MJO is an _____ ______ or “wave” occurring in the global tropics

A

intraseasonal fluctuation

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3
Q

The MJO results in variations in several important atmospheric and oceanic parameters including:

A
  • lower and upper-level wind speed and direction (divergence)
  • cloudiness and rainfall
  • surface pressure
  • sea surface temperature (SST)
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4
Q

The MJO is a naturally occurring component of our coupled ____-____ system

A

ocean-atmosphere

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5
Q

The typical length of the MJO cycle or wave is approximately ___-___ days

A

30-60 days

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6
Q

The MJO is characterized by ____ propagation of regions of enhanced and suppressed tropical rainfall, primarily over the ____ and ____ Oceans

A

eastward

Indian and Pacific

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7
Q

The anomalous rainfall is often first evident over the ___ Ocean, and remains apparent as it propagates eastward over the very warm waters of the ____ and ____ tropical Pacific

A

Indian

western and central

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8
Q

Over the cooler ocean waters of the eastern Pacific, the pattern of tropical rainfall generally becomes ____, but often reappears over the tropical ____ and ___

A

nondescript

Atlantic and Africa

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9
Q

Along with these variations in tropical rainfall with MJO, there are distinct patterns of ___ and ____-level divergence and atmospheric circulation anomalies in the ____ and ____

A

lower- and upper-level

tropics and subtropics

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10
Q

These features extend around the globe and are not confined to the eastern hemisphere. they provide important info regarding the regions of ___ and ____ motion associated with particular phases of the ____

A

ascending and descending

oscillation

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11
Q

As active convection moves eastward from the central Pacific to the Atlantic, the feature ____ as it moves into the Western Hemisphere

A

weakens

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12
Q

When convection is active in the Indian Ocean and Indonesia, in the ___ levels, anomalous easterlies exit the area of enhanced convection in the upper levels of the atmos associated with ____ gyres stradding the equator in both hemispheres ____ and to the ___ of the convection.

A

upper

anticyclonic

west

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13
Q

Conversely in the upper levels, ____ gyres straddle the equator to the ___ in areas of suppressed convection in both hemispheres

A

cyclonic

east

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14
Q

When convection is active in the Indian Ocean and Indonesia, in the ___ levels, anomalous easterlies are evident to the ___ of the area of enhanced convection, associated with ____ gyres straddling the equator in both hemispheres

A

lower

east

anticyclonic

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15
Q

in the lower levels, anomalous ____ are evident within and to the west of the area of enhanced convection, associated with ___ gyres straddling the equator in both hemispheres

A

westerlies

cyclonic

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16
Q

The low level gyres are generally ___ than those at upper levels

A

weaker

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17
Q

As the MJO propagates ____ through the central Pacific and eastern Pacific, the lower and upper level cyclonic/anticyclonic circulation anomalies become ___ recognizable and coherent but remain an important component in redistributing mass and convergence/divergence around the global tropics

A

less recognizable

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18
Q

Enhanced ____ often accompanies the upper level ____ phase of the MJO

A

rainfall

U/L divergent

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19
Q

However, with MJO, rainfall may be suppressed across portions of the equatorial eastern Pacific Ocean due to ____ ocean water there

A

colder

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20
Q

Anomalously strong 850mb ____ occur in the tropics within the lower-level ___ (___) phase of the MJO

A

easterlies

divergent (dry)

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21
Q

Anomalously strong 850mb ____ occur in the tropics within and immediately west the lower-level ____ (___) phase of the MJO

A

westerlies

convergent (wet)

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22
Q

850 mb equatorial westerlies south of Mexico are often associated with an enhanced ____ ____ over the NW Caribbean and southern Gulf of Mexico

A

monsoon trough

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23
Q

Equatorial westerlies produce ____ shear across the NW Caribbean and southern Gulf of Mexico, which favors ____ ____ formation there.

A

cyclonic

tropical cyclone

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24
Q

The MJO can substantially modulate the _____ of monsoon systems around the globe

A

intensity

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25
Q

When does the MJO substantially modulate the intensity of monsoon systems for the following areas?:

  • The Australian Monsoon?
  • The Asian Monsoon?
  • The South American Monsoon?
  • The North American Monsoon?
A
  • Australian: SH summer
  • Asian: NH summer
  • S Am.: SH summer
  • N Am.: NH summer
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26
Q

The _____ (___) phase of the MJO can affect both the timing of the monsoon onset and the intensity of the monsoon

A

divergent (wet)

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27
Q

The ____ (___) phase of the MJO can prematurely end a monsoon and also initiate breaks during already existing monsoons

A

convergent (dry)

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28
Q

There is evidence that the MJO influences the ___/___ cycle

A

El Nino/La Nina cycle

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29
Q

The MJO does not cause El Nino, but can contribute to the ___ of development, and perhaps the overall ___ of El Nino episodes

A

speed of development

overall intensity

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30
Q

The MJO is known to ____ tropical cyclone activity in the Indian, Pacific, Atlantic Oceans, and the Gulf of Mexico

A

modulate

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31
Q

The MJO modulates this activity (particularly for the strongest storms) by providing a ___-scale environment that is favorable or unfavorable for development

A

large-scale

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32
Q

Westerly wind anomalies at the ____ in and just behind the MJO’s area of enhanced convection may generate mirror-image ____ gyres straddling the equator respectively

A

surface

cyclonic

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33
Q

At the same time, in the ___ levels, mirror-image ____ gyres develop along and just behind the area of convection

A

upper-levels

anticyclonic

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34
Q

The net result of the mirror-image cyclonic gyres at the surface, and anticyclonic gyres at the U/L is:

A

1) A reduction of U/L wind shear for westward-moving tropical cyclones
2) an increase in U/L divergence

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35
Q

The strongest tropical cyclones tend to develop during the upper-level ____ (__) phase of the MJO

A

divergent (wet)

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36
Q

As the MJO progresses eastward, the favored region for tropical cyclone activity also shifts ___ from the Indian Ocean to the Pacific Ocean and eventually to the Atlantic Ocean

A

eastward

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37
Q

Sea Surface Temperatures must be sufficiently ___ and vertical wind shear must be sufficiently ___ for tropical cyclones to form and persist

A

warm

weak

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38
Q

Enhanced tropical rainfall in the ___ and ___ Pacific can contribute to extreme rainfall events in ___ North America

A

western and central Pacific

western North America

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39
Q

A ____ ____ is an event in which an eastward moving upper level divergent (wet) phase of the MJO in the central or eastern tropical Pacific and a retrograding (i.e. westward moving) mid-latitude jet stream trough in the high latitudes.

A

Pineapple Express

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40
Q

There is a strong year-to-year variability in MJO activity, with periods of ____ activity followed by long periods in which the oscillation is ___ or ____

A

strong activity

weak or absent

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41
Q

There is evidence that the _____ variability of the MJO is partly linked to the El Nino cycle

A

interannual

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42
Q

Strong MJO activity is often observed during ___ La Nina yeras or during times when El Nino or La Nina is ____

A

weak

absent

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43
Q

Weak or absent MJO activity is typically associated with ___ El Nino episodes

A

strong

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44
Q

The ____ ____ is a zonal (east-west) direct circulation in the tropical Pacific

A

Walker Circulation

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45
Q

A ___ circulation is oriented parallel to latitude lines

A

zonal

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46
Q

A ____ circulation is composed of a circulation where warm air is rising and cold air is sinking

A

direct

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47
Q

Warm air ____ over the west Pacific during a normal Walker circulation regime

A

rises

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48
Q

Cooler air ___ over the cooler water of the east Pacific

A

sinks

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49
Q

Under normal conditions, the west Pacific experiences ____ rainfall, whereas the east Pacific (particularly along and south of the equator) is ___

A

heavy

dry

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50
Q

With the Walker Circulation, through which months are there normal conditions?

A

December-February

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51
Q

At the ____, the West and East Pacific are linked by westward-directed trade winds

A

surface

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52
Q

In the ____-___, the West and East Pacific are linked by eastward-directed winds

A

upper-troposphere

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53
Q

When the Walker Circulation is strong, ____ pressure resides over the tropical West Pacific

A

low

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54
Q

When the Walker Circulation is strong, ____ pressure resides over the tropical East Pacific

A

high

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55
Q

When the Walker Circulation is strong, the ____ winds are strong over the Pacific

A

trade winds

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56
Q

When the Walker Circulation is strong, the ___ Pacific is wet and stormy

A

West

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57
Q

When the Walker Circulation is strong, the ____ Pacific is dry and tranquil

A

East

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58
Q

______ isadisruptionoftheocean‐atmosphere
systeminthetropicalPacifichavingimportant
consequencesforweatheraroundtheglobe.

A

ElNiño

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59
Q

ElNinoischaracterizedbyamajor_____of

watersinthe________and_______ _____ Ocean.

A

warming | tropicalcentral | easternPacific

Ocean

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60
Q

El Nino is called “___ ____” because it occurs or was first noticed along the west coast of South America around ____ time

A

“The Child” | Christmas Time

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61
Q

El Nino occurs every ___ - ___ years and is characterized by a major ____ or even total ____ of the ____ Circulation

A

2-10 years | major weakening | total reversal | Walker Circulation

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62
Q

Drastic changes in ____ _____ are experienced not only over the tropical Pacific, but throughout the world

A

weather patterns

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63
Q

El Ninos are characterized by a “_____” SOI

A

negative

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64
Q

What does SOI stand for?

A

Southern Oscillation Index

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65
Q

SOI = _____ - _____

A

SOI = Tahiti SLP - Darwin SLP

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66
Q

When Tahiti SLP is significantly ____ than Darwin, the SOI is _____ and an El Nino may be occurring

A

lower | negative

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67
Q

In December 2008, the Climate Prediction Center started using the ____ ___ ___ to monitor El Nino

A

Oceanic Nino Index (ONI)

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68
Q

El Nino-related atmospheric and oceanic data is routinely measured by an array of ____ in the Central and Eastern Tropical Pacific

A

buoys

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69
Q

ONI is based on ____ departures from average in the Nino ___ region, and is now the principle measure of monitoring and assessing El Nino

A

SST departures | 3.4

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70
Q

The ONI is based on a ____-month running mean of SST departures in the Nino 3.4 Region

A

3-month

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71
Q

The ONI is used to place current events into a _____ perspective

A

historical

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72
Q

NOAA’s operational evaluation of El Nino and La Nina are keyed to the ____

A

ONI

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73
Q

____ ____ is characterized by a ____ ONI greater than or equal to +0.5 deg C

A

El Nino | positive

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74
Q

___ ____ is characterized by a ____ ONI less than or equal to -0.5 deg C

A

La Nina | negative

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75
Q

By historical standards, to be classified as a full-fledged El Nino or La Nina episode, these thresholds must be exceeded for a period of at least ___ consecutive overlapping ___-month seasons

A

5 consecutive | 3-month seasons

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76
Q

CPC considers El Nino or La Nina conditions to occur when the monthly Nino 3.4 SST departures ____ or ____ +/- 0.5 deg C along with consistent atmospheric features

A

meet or exceed

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77
Q

These anomalies must also be _____ to persist for ___ consecutive months

A

forecasted | 3 consecutive months

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78
Q

The most recent ONI value (January-March 2014) is ___ deg C

A

-0.7 deg C

79
Q

When the Walker Circulation is weak (or reversed), ____ forms

A

El Nino

80
Q

When the Walker Circulation is ___ (or _____), great havoc occurs in the world’s weather patterns

A

is weak (or reversed)

81
Q

When the Walker Circulation is weak (or reversed), great hardship is experienced by many ____ and much ____ across the world

A

many people | much wildlife

82
Q

When an El Nino is occurring, ___ pressure moves to the tropical Central and East Pacific

A

Low

83
Q

When an El Nino is occurring, ____ pressure forms over the tropical West Pacific

A

High

84
Q

When an El Nino is occurring, the ____ winds weaken or reverse over the Pacific

A

trade winds

85
Q

When an El Nino is occurring, the ____ ____ becomes dry (drought is common in rainforests)

A

West Pacific

86
Q

When an El Nino is occurring, the ____ and ___ Pacific become very stormy

A

Central and East Pacific

87
Q

During the formative stage of El Nino (late summer and fall), the Walker Circulation _____

A

weakens

88
Q

During the formative stage of El Nino (late summer and fall), pressure ___ in east Pacific and ____ in West Pacific

A

falls | rises

89
Q

During the formative stage of El Nino (late summer and fall), the SOI becomes ____

A

negative

90
Q

During the formative stage of El Nino (late summer and fall), the ONI becomes ____

A

positive (>0.5 deg C)

91
Q

During the formative stage of El Nino (late summer and fall), trade winds ____ (_____)

A

fail (weaken)

92
Q

During the formative stage of El Nino (late summer and fall), an _____ ____ wave moves from West to East Pacific

A

Equatorial Kelvin Wave

93
Q

During the formative stage of El Nino (late summer and fall), ____ SST’s shift eastward as sea level mound moves eastward

A

warm SST’s

94
Q

During the formative stage of El Nino (late summer and fall), ____ in East Pacific weakens

A

upwelling

95
Q

During the formative stage of El Nino (late summer and fall), convection and precipitation shifts _____

A

eastward

96
Q

During the mature stage of El Nino (Winter and Spring), the Walker Circulation ____

A

reverses

97
Q

During the mature stage of El Nino (Winter and Spring), ____ pressure resides in central and east Pacific

A

Low pressure

98
Q

During the mature stage of El Nino (Winter and Spring), ____ pressure resides in west Pacific

A

high

99
Q

During the mature stage of El Nino (Winter and Spring), the SOI becomes strongly ____

A

strongly negative

100
Q

During the mature stage of El Nino (Winter and Spring), the ONI becomes strongly ____

A

strongly positive

101
Q

During the mature stage of El Nino (Winter and Spring), trade winds ___ or actually ____

A

calm or actually reverse

102
Q

During the mature stage of El Nino (Winter and Spring), Equatorial Kelvin Wave moves from ____ to ___ Pacific

A

West to East

103
Q

During the mature stage of El Nino (Winter and Spring), warm SST’s cover ____ and ___ Pacific

A

central and east Pacific

104
Q

During the mature stage of El Nino (Winter and Spring), sea level ___ resides in east Pacific (higher sea level along South American Coast)

A

Sea Level Mound

105
Q

During the mature stage of El Nino (Winter and Spring), upwelling of cold water in East Pacific is ____

A

absent

106
Q

During the mature stage of El Nino (Winter and Spring), ____ _____ cover central and east Pacific

A

heavy thunderstorms

107
Q

During the dissipating stage of El Nino (late spring and summer), the Walker Circulation begins to ____

A

strengthen

108
Q

During the dissipating stage of El Nino (late spring and summer), pressure ____ in west Pacific and ____ in east Pacific

A

falls | rises

109
Q

During the dissipating stage of El Nino (late spring and summer), the SOI becomes ____

A

positive

110
Q

During the dissipating stage of El Nino (late spring and summer), the ONI becomes ____ or slightly ____

A

neutral or slightly negative (<0.5 deg C)

111
Q

During the dissipating stage of El Nino (late spring and summer), trade winds ____

A

strengthen

112
Q

During the dissipating stage of El Nino (late spring and summer), the Equatorial Kelvin Wave ____

A

dissipates

113
Q

During the dissipating stage of El Nino (late spring and summer), warm SSTs ____ back to the west Pacific

A

slosh back

114
Q

During the dissipating stage of El Nino (late spring and summer), sea level mound ____ in east Pacific (sea level ____ in west Pacific_

A

disappears | rises in west Pacific

115
Q

During the dissipating stage of El Nino (late spring and summer), upwelling of cold water in East Pacific ____

A

resumes

116
Q

During the dissipating stage of El Nino (late spring and summer), heavy thunderstorms move back to ____ Pacific

A

west

117
Q

During the dissipating stage of El Nino (late spring and summer), ____ weather returns to east Pacific

A

dry

118
Q

___ ____ is a major cooling of the tropical east Pacific Ocean

A

La Nina

119
Q

La Nina generally (but not always) follows a strong ___ ____ event and is characterized by an overly-strong ____ _____

A

El Nino | Walker Circulation

120
Q

La Ninas are characterized by a “____ ____” SOI

A

strongly positive

121
Q

La Ninas are characterized by a “____ ____” ONI

A

strongly negative

122
Q

There is growing evidence that anomalously strong MJO activity often ____ major El Nino warm events by __ - ___ months

A

precedes | 6-12 months

123
Q

Vigorous bursts of equatorial westerly winds, associated with the frequent positive phases of the MJO, may develop an oceanic ____ ____ which forces a dome of warm water eastward from the West Pacific.

A

Kelvin wave

124
Q

This Kelvin Wave would help suppress cold upwelling in the East Pacific, helping to ____ SLP, ___ the zonal SLP gradient across the Pacific, and ___ the trade winds, thus ____ an El Nino

A

lower SLP | relax zonal SLP gradient | relax trade winds | initiating an El Nino

125
Q

The strength of El Nino events appears to ____ with the strength of preceding MJO activities

A

increase

126
Q

_____ variability in the atmosphere (wind and pressure), which is often related to the Madden-Julian Oscillation (MJO), can significantly impact ____ and _____ conditions across the Pacific Ocean

A

Intraseasonal | surface and subsurface

127
Q

Significant weakening of the low-level easterly winds usually initiates an ____-propagating oceanic Kelvin wave

A

eastward

128
Q

What does NAO stand for?

A

North Atlantic Oscillation

129
Q

The NAO Index is defined as the difference of ____ (or ___ ____) anomalies between two regions: One near the ____ and one near ____

A

SLP (or 500mb heights) | Azores region and Iceland

130
Q

NAO Index = (SLP anomalies (____) - SLP anomalies (____))Regions

A

Azores - Iceland

131
Q

After ___ ____, the NAO pattern is one of the most dominant modes of global climate variability

A

El Nino

132
Q

The temperature see-saw in Greenland is now known to be a manifestation of the ___

A

NAO

133
Q

The ____ dictates climate variability from the eastern seabord of the US to Siberia and from the Arctic to the subtropical Atlantic, especially during Winter

A

NAO

134
Q

The ____ index (i.e. ____) NAO is associated with a net displacement of air from over the Arctic and Icelandic regions towards the subtropical belt near the Azores and the Iberian peninsula

A

high index (i.e. Positive) NAO

135
Q

The mass displacement of air associated with a Positive NAO _____ the Icelandic Low near the SE coast of Greenland and also ____ the subtropical H in the Atlantic

A

strengthens | strengthens

136
Q

The mass displacement of air associated with a Positive NAO results in more intense _____ over the N Atlantic ocean

A

westerlies

137
Q

_____ temperatures are also observed over the W Atlantic and eastern US

A

Warmer

138
Q

The stronger Atlantic Subtropical High also strengthens the ____ ____ over the Tropical Atlantic

A

trade winds

139
Q

___ ____ is often blown across the tropical Atlantic toward the Caribbean and FL

A

African dust

140
Q

Increased _____ of cold water off the NW coast of Africa help to keep sfc temps cooler over the tropical E Atlantic. ___ weather often is enhanced here as well

A

Upwelling | dry weather

141
Q

The ____ index (i.e. ____) NAO is associated with a net displacement of air from over the subtropical belt near the Azores and Iberian Peninsula northward to the Arctic and Icelandic regions

A

Low Index (i.e.: Negative)

142
Q

The net displacement associated with a Low/Negative NAO Index ____ the Icelandic Low and forces it to become much more ____ in location. It also ___ the subtropical H in the Atlantic, resulting in ___ intense westerlies over the N Atlantic ocean

A

weakens | more variable in location | weakens subtropical H | less intense westerlies

143
Q

With a negative NAO, ____ patterns often develop in the Atlantic jet stream pattern

A

Blocking patterns

144
Q

With a negative NAO, Arctic High pressure is better developed in the ___ regions and often ____ into northern and central Europe when significant blocking patterns develop over the Atlantic

A

polar | invades

145
Q

With a negative NAO, ___ than normal European winters are often experienced with much more ____ and precipitation in the eastern Mediterranean Sea area

A

colder than normal | more storminess

146
Q

With a negative NAO, a ____ subtropical H promotes ____ trade winds in the tropical Atlantic

A

weaker | weaker

147
Q

With a negative NAO, ____ upwelling of cold water off the NW coast of Africa help to keep surface temperatures _____ over the tropical eastern Atlantic

A

reduced | warmer sfc temps

148
Q

Blocking in the N Atlantic is much more prevalent during ____ phases of NAO

A

negative phases of NAO

149
Q

During a negative NAO event, deep _____ reside over E N Am and Europe, bringing unusually ____ conditions

A

deep troughs | unusually cold

150
Q

It appears that the link between El Nino in the tropical Pacific, and the NAO, is relatively ____

A

weak

151
Q

The NAO may arise from what influences?

A

1) Stochastic interaction between storms
2) Climatologial stationary eddies
3) Time-mean jet stream pattern
4) Long-term stratospheric influences on the troposphere
5) The intensity and distribution of tropical convection
6) Long-term feedback from oceanic circulation patterns and sea ice changes

152
Q

With the long-term statospheric influences on the troposphere, the influence of volcanic ash tends to promote ___ phase

A

+ PNA

153
Q

With the long-term statospheric influences on the troposphere, ozone depletion tends to promote ____ phase

A

+ PNA

154
Q

With the long-term statospheric influences on the troposphere, greenhouse gas accumulation may promote ___ phase

A

+ PNA

155
Q

The month-to-month and year-to-year changes in the phase and amplitude of the NAO are largely _____

A

unpredictable

156
Q

External forces may be able to ____ the NAO pattern into positive and negative phases over a particular month or season

A

nudge

157
Q

What does AO stand for?

A

Arctic Oscillation

158
Q

The __ is the dominant pattern of non-seasonal SLP variations N of 20N

A

AO

159
Q

The AO is characterized by ____ anomalies of one sign in the Arctic and anomalies of opposite sign centered in the mid-latitudes

A

SLP anomalies

160
Q

AO Index = (SLP Anom (____) - SLP Anom (___)) Regions

A

Mid-Latitude | Arctic

161
Q

Positive AO is associated with ___ pressure in the mid-latitudes and ____ pressure near the N Pole

A

HIGHER | LOWER

162
Q

Positve AO is associated with ___ zonal flow of westerlies across the mid-latitudes

A

fast strong zonal flow

163
Q

Positive AO is associated with ___ winter weather in US and Europe

A

mild winter weather

164
Q

Positive AO is associated with ____ arctic sea ice

A

melting

165
Q

Positive AO is known as the ____ phase of the AO

A

warm phase

166
Q

Negative AO is associated with ____ pressure in mid-lat and ____ pressure near N Pole

A

LOWER | HIGHER

167
Q

Negative AO is associated with significant high-lat ___ in jet stream, which leads to ____ meridional flow and ___ zonal flow of westerlies in mid-lat

A

blocking | greater merid | weaker zonal flow

168
Q

Negative AO is associated with ____ cold winter weather in US and Europe, and ____ arctic sea ice

A

severe | expanding

169
Q

Negative AO is known as ___ phase of AO

A

cold phase

170
Q

The month-to-month and year-to-year changes in phase and amplitude of NAO and AO are largely ____

A

unpredictable

171
Q

What does PNA stand for?

A

Pacific-North American Pattern

172
Q

The PNA is associated with a ___ wave pattern with centers of action over the N Pacific and over N Am

A

Rossby wave pattern

173
Q

A positive PNA is characterized by ___ 500 mb height anomalies over the N Pacific and E N Am/W Atlantic

A

low 500 mb heights

174
Q

A positive PNA is characterized by ____ 500 mb height anomalies over W N Am

A

high 500 mb heights

175
Q

What does PDO stand for? When was it discovered?

A

Pacific Decadal Oscillation. 1997

176
Q

____ ___ play a huge role in the short and long-term climate variability

A

Natural Cycles

177
Q

The Earth has shown no statistically significant warming in approximately the last __-__ years

A

15-17 years

178
Q

The ____ is a long-lived El-Nino-like pattern of Pacific climate variability

A

PDO

179
Q

The PDO Index is defined by the N Pacific monthly __ ____ ___ variability

A

monthly SST variability

180
Q

PDO Index = SST (___) - SST (___)

A

SST (E Pacific) - SST (Central Pacific)

181
Q

Warm (____) Index periods contain ____-than-normal waters in N central Pacific Ocean and ____-than-normal waters along W coast of N Am

A

(+PDO) | cooler | warmer

182
Q

Cold (___) Index periods contain ___-than-normal waters in N central Pacific Ocean and ___-than-normal waters along W coast of N Am

A

(-PDO) | warmer | cooler

183
Q

20th century PDO “events” persisted for __-__ years, while typical ENSO events persisted for __-___ months

A

20-30 years | 6-18 months

184
Q

The climatic fingerprints of the PDO are most visible in the ___ ___/___ ___ sector, while secondary signatures exist in the ____ - the opposite is true for ENSO

A

most visible in N Pacific/N Am | secondary exist in tropics

185
Q

The effects of the PDO are most drastic in the ____ ____

A

Pacific Northwest

186
Q

A positive PDO generally correlates with ___ conditions and ___ temperatures

A

dry conditions | warmer temperatures

187
Q

A negative PDO generally correlates with ___ conditions and ___ temperatures

A

wet conditions | cooler temperatures

188
Q

Warm eras have seen ___ coastal ocean biological productivity in Alaska and ____ productivity off W coast of US

A

enhanced in Alaksa | inhibited off W coast

189
Q

Cold PDA eras have seen ____ marine ecosystem productivity in Alaska and ___ productivity off W coast of US

A

Inhibited | enhanced

190
Q

True or False? Causes of PDO are not currently known.

A

True!

191
Q

Research indicates that there may be indicators up to ___ years in advance

A

10 years

192
Q

If the PDO unexpectedly changes phase during the forecast period, then error ____ in extended weather predictability

A

increases

193
Q

Some new research indicates that PDO cycle may be related to ___ cycles

A

solar

Synoptic Met II => Final Exam (6 decks)

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