according to which it is only the mass convergence aloft that has an effect on the hydrostatic surface pressure

vorticity (PV) downstream of high topography

Scientific colour maps

2015 LEAF

apparently nonstationary visualbehavior arises because of the non-Gaussian statistic

purely random fluctuations expected from stationary timeseries

The interactions can result in predator–prey cycles in moisture mode activity and Hadley cell strength that are akin to ITCZ breakdown.

iltered water vapor imagery

external gravity (or Lamb) waves excited by the Tonga explosion

Multi-Radar Multi-Sensor (MRMS) Operational Product Viewer

Saturday Night Live's 10 best holiday sketches of all time, ranked

ATM 752  Vortex Dynamics

Advanced Graduate Courses

Statistical Modeling

Predictability

Numerical Methods

Air-Sea Interaction

ENSO

Coastal

Turbulence

Defininations: heatwave: at least three consecutive days in which the maximum 2-meter air temperature exceeds the 90th percentiles.  The consecutive days of heatwave is counted within a month, which is the same in other variables, such as CDD, CSDI, CWD, LCS, and LWS.   cold spell: the minimum 2-meter air temperature be less than the 10th percentiles.   warm spell: the maximum 2-meter air temperature exceeds the 90th percentiles.    percentiles: in this collection they are based on daily temperature and precipitation fields, and calculated using a running window of +/- 7 days centered on each day of the year for the climatology period of 1991-2020 in Version 2 (1981-2010 in Version 1).

Climate Statistics Products

maximum number of consecutive days when precipitation < 1 mm

percentage of time when daily max 2-m temperature < 10th percentile

percentage of time when daily min 2-m temperature

Monthly Percentiles

Daily

The monthly percentiles indicate atwhich percentile the monthly mean falls relative to the 1991-2020 period.

ercentiles were calculated using a running window of +/- 7 days centered on each day ofthe year for the climatology period of 1991 through 2020 for version 2 products.

MRMS multi-radar multi-senso

Effects of SST on surface wind stress

Gravity wave packets

Baiu Front Okinawa

Column water vapor in the spin-up of an aquaplanet

Rossby wave dispersion

evolving lowpass filtered fields act as a "steering flow” for the high pass filtered perturbations

Equatorially-trapped waves

ozone

PV on the 850 hPa surface

strength of the condensation heating in the model can be controlled by specifying the relative humidity

both LC1 and LC2

a new center develops nearer to the coast and quickly becomes dominant

intense cyclone comes ashore near San Francisco

well defined

10-day interval, six or seven systems

shear instability

cold continental air masses flow over the warmer offshore waters

Hourly CO concentration

summer drawdown due to the uptake of CO2 by the boreal forests

those shown in Part II move in tandem with features embedded in the base of the updraft, indicative of a deeper structure

aerosols are categorized by tint: dust (orange), smoke (red) organic/black carbon (green), and sulfates (white)

CONDA_SUBDIR=osx-64 conda create

a cloud or moisture feature

Satellite Derived Winds

Derived Motion Winds

Geo2Grid

conda install -c pyviz hvplot Copy to clipboard

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The Explorer

Digital Storytelling Tools

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MODEL INTERPRETATION

The Brave browser is

ATMOSPHERIC MOIST CONVECTION Annual Review

Up-scale growth thus occurs as a continuing amplification oflarge scales after small scales saturate, which begs the question of what sets the shape of the saturation(climatological) power spectra. Wind spectra are nearly power-law with a logarithmic slope of about −5/3in the free troposphere, remarkably so in the 2D runs and clearly distinct from slope −2 (a null hypoth-esis of spectrally white wind divergence). A common interpretation of −5/3 slope − as indicative of a cas-cade, a steady conservative transfer of energy from source to sink scales by interactions that are local inlog-wavelength space − is hard to apply to these moist tropical waves.

/MERRAero

Extra Chemical Fields

gmao/geos-cf

Spray

The Great Master’s-Degree Swindle

that more knowledge about climateintervention approaches and their consequences will help society make informed, justdecisions about the deployment of climate intervention. AGU is not taking a position aboutspecific climate interventions, but AGU is making the case that a robust body of scientificevidence about climate intervention and an ethical framework should be available

You can try Via by clicking the “Paste a link” button at the top of the page.

CONCEPT MAPPING: A USEFUL TOOL FOR SCIENCE EDUCATION

Wereserve some flexibility in how exactly to define these quantities

define the so-called null hypothesis, which in some sense states the opposite

Middle band is for AL/SI = 1/4, e.g., 1 season sampled once per year.

Distribution of Helicity, CAPE, and Shear in Tropical Cyclones

Factors contributing to tornadogenesis in landfalling Gulf of Mexico tropical cyclones

Parameter for Forecasting Tornadoes Associated with Landfalling Tropical Cyclones

Environmental ingredients for supercells and tornadoes within Hurricane Ivan.

The dominant deep convective heating process changes from latent heating at low levels to eddy heat-flux convergence in the upper troposphere. This requires a substantial updraught-environment temperature difference

within

3.1 Static instability

ifference between an airparcel and its surrounding environmen

The dynamics of many mesoscale phenomena are oftenmore intuitive if the vertical momentum equation is writtenin terms of a buoyancy force and a vertical perturbationpressure gradient force.

portrait of the emergence structure of the system.

hose which minimise dynamical dependence) characterise emergenc

epimorphism

in the context of the environment E

microscopic history adds nothing to the capacity of the macroscopic variable to self-predic

Widths of the earliest detectable low-level updrafts associated with sustained precipitating deep convection were ~3–5 km, larger than updrafts associated with surrounding boundary layer turbulence (~1–3 km wide)

close agreement with Fig. 1.11.

The rotational and divergent components of atmospheric circulation on tidally locked planets

We apply theHelmholtz decomposition to the horizontal velocity fields out-put from two well-studied general circulation mode

25

a superrotating equatorial jet, planetary-scale station-ary waves, and thermally driven overturning circulatio

tidally locked planets

The two physical components of the rotational circulation in Fig. 2

Helmholtz decomposition of horizontal velocityufor the terrestrial simulation at 0.4 bar.

zonal-mean jet (red) and the eddy stationary waves (green

Divergent, overturning circulation (blue) rises at thesubstellar point

dividing the circulation of a terrestrial tidallylocked atmosphere into rotational and divergent componentscorresponds to a division into two physically meaningful circu-lations. The rotational circulation is primarily composed of thestationary Rossby waves forced by the divergent circulation andthe zonal-mean jet produced by the stationary part of the atmo-spheric circulation.

Rotation rateΩ(s−1)7.29×10−6

height and velocity fields at 0.4 bar

The energetics of this system describe exchanges among the divergent and the rotational energy components. The energy equations are as follows.

Boyle, James S. October 1996, 34 pp.  The 200 hPa kinetic energy is represented by means of the spherical harmonic components for the AMIP simulations, the NCEP/NCAR reanalysis and the ECMWF reanalysis(ERA). The data used are the monthly mean wind fields for 1979 to 1988. The kinetic energy is decomposed into the divergent (DKE) and rotational (RKE) components and emphasis is placed on examining the former.

Like Greg, I read a collection of rationality blogs—Marginal Revolution, Farnam Street, Interfluidity, Crooked Timber.

Why Is It So Hard to Be Rational?

Climate Laboratory

f the major premise is made sensible by making itprobabilistic, not absolute, the syllogism becomes for-mally incorrect and leads to a conclusion that is not sen-sible

Norbert Wiener, a child prodigy and a great mathematician, coined the term 'cybernetics' to characterize a very general science of 'control and communication in the animal and machine'. It brought together concepts from engineering, the study of the nervous system and statistical mechanics (e.g. entropy). From these he developed concepts that have become pervasive through science (especially biology and computing) and common parlance: 'in-formation', 'message', 'feedback' and 'control'. He wrote, 'the thought of every age is reflected in its technique . . . If the seventeenth and early eighteenth centuries are the age of clocks, and the later eighteenth and nineteenth centuries constitute the age of steam engines, the present time is the age of communication and control.'

moisture quasiequilibrium

where slow and shigh are respectively the saturated moist entropy averaged over the altitude ranges of 1–3 km and 5–7 km

where is threshold entropy, defined as the average of the saturated moist entropy in the 1.5–2 km layer, minus the boundary layer moist entropy sbl averaged over the 0–1 km layer

The instability index is defined

Gallery

he MPO Ph.D. degree requires a minimum of 30 course credits, of which a minimum of 9 course credits should be taken from 700 level courses.

at least one 3-credit course outside the MPOprogram

MPO) GRADUATE HANDBOOK,2020-2021

Misinformation

Figure 7.15

Quirky Critters

Stop explaining black box machine learning models for high stakes decisions and use interpretable models instead

vertical motion

DYNAMO data and RAs

A peculiar feature in MERRA-2 is that its moisture analysis increment (estimated by budget residual) is positive and largest even though CWV anomalies are larger than those in the other RAs

ratio of anomalous OLR (a proxy of column longwave heating) to precipitation

The contribution of LW to MSE propagation in MERRA-2 and JRA-55 is relatively small, which is likely related to the relatively weak cloud–radiation feedback strength

the models used to create the modern RAs need additional MSE source to maintain MJO MSE anomalies

In MERRA-2 (JRA-55), horizontal MSE advection tends to dampen (amplify) MSE anomalies

Over the Indo-Pacific warm pool, the mean MSE is relatively high in MERRA-2 and ERA-I

LRP highlights the regionsof greater relevance for the ANN to predict the year by propagating an output sample back-ward through the frozen nodes of the ANN until it reaches the input layer

virtual sv(red broken), moist h

heavy rainfall in equatorial East Africa

Total precipitation

“reforecasts” of the weather, that is, retrospective forecasts spanning the period 2000-2019

Precipitable water (kg m​-2​, i.e., mm)

It is not currently possible to “un-flag” an annotation — if an annotation is flagged by mistake, the group creator can choose not to hide it.

The Matrix Cookbook

as-yet-undiscovered organizing principles might be at work at the mesoscopic scale, intermediate between atomic and macroscopic dimensions

a damaged species: associate professors. Long forgotten, these tenured professors find themselves burdened with extensive service and administrative tasks

absolute vorticity

background

Advζ, AdvT, and the Q term, respectively,

The total ω may be separated into a component explained by the QG ω equation (ωqg) and the remainder [ωaqg, calculated as a residual term in Eq. (2)]. A significant advantage of the QG ω equation is its linearity, and thus, we may directly decompose ωqg into components forced by the large-scale advective forcings and diabatic heating.

The QG ω equation may be written as

thermal efficiency of the atmospheric heat engine isless than 1%

there will alwaysremain some degree of uncertainty (or errors) inthe initial conditions and, due to the nonlinearityof atmospheric motions, these errors inevitablyamplify with time. Beyond some threshold forecastinterval the forecast fields are, on average, no morelike the observed fields against which they are veri-fied than two randomly chosen observed fields forthe same time of year are like one another. For theextratropical atmosphere this so-called limit ofdeterministic predictabilityis believed to be on theorder of 2 weeks

cross-isobar flow V is the one and onlysource term

It can be shownthat, in the integral over the entire mass of theatmosphere, the generation of kinetic energy by theV term in (7.42) is equal to the release ofpotential energy associated with the rising of warmair and sinking of cold air.

0

Exercises

1 PVU106m2s1K kg1

Ertel’s19potential vorticity

LLCS consumes far too much boundary layer moisture

standard value used in our simulations is the “pure mixing time scale” of 3,600 s

the bottom row shows the second eigenvectors, V2

Hence, instead of truncating, we rotate β and γ back into θ,q on levels by forming the 2m component vector and the 2m × 2m matrix to interpret our results

the vast majority of output convective behavior can be described with relatively few eigenvectors. We typically retain two or three for discussion in the results sections and use 10 when the emulators are run online as part of the GCM

We predict Q from P rather than predicting Y from X because correlations between values of θ and q on different vertical levels that could cause large errors in our statistical analysis are avoided

Cases from the equally spaced group deemed nonconvecting (cpΔθtrop < 0.05 MJ m−2) are then discarded, as are an equal number of nonconvecting cases. This leaves an equal number of convecting and nonconvecting cases

The choice of 60,000 cases was made, as it is realistic to perform analysis on matrices of this size with available computing resources. It is found that using smaller sample sizes has little effect on accuracy

nonconvecting cases (defined as cpΔθtrop <0.05 MJ m−2, equivalent to a temperature change ΔTtrop  ≃ 10.1 K day−1,

the cases closest to 30,000 equally spaced values of cpΔθtrop from its minimum to its maximum value

A two‐step linear statistical emulator is used

we form a “case.”

The overall aim is not to replace conventional parameterization nor to improve GCM integration speed but to understand our parameterizations in the context of process knowledge and provide tools for parameterization development and interpretation of climate model projections.

The derived response matrices must also be put in the GCM in place of the original parameterization, as was done by Kelly et al. (2017) and Mapes et al. (2019)

thickness of the layer

Z

Cis referred to as the circulation

Exercises

spatial organization of tropical deep convection, can manifest itselfin two ways: through a decrease in the total area covered by convection and/or through a decrease in thenumber of convective areas

(a) geography-relative and (b) recurvature-relative frameworks.

Recurvature-relative composite analyses of all recurving WNP TCs

zonal group speeds based on the leading edge [cg = 42° day−1 (36.5 m s−1)] and peak amplitude [cg = 37° day−1 (32.1 m s−1)] of the RWT, respectively, whereas the yellow arrow indicates the estimated Rossby wave zonal phase speed [cp = 6° day−1 (5.2 m s−1)]

David (1997)−2.0543Soulik (2006)−1.7317Susan (1988)−2.0144Mamie (1985)−1.6818Dale (1996)−2.0045Phanfone (2002)−1.6719Thelma (1980)−2.0046Agnes (1981)−1.6720Lola (1986)−1.9747Dianmu (2004)−1.67

Polly (1995)−1.9248Ann (1999)−1.6622Dan (1995)−1.8949Podul (2001)−1.6623Nabi (2005)−1.8850Ma-on (2004)−1.6524Dinah (1987)−1.8751Krosa (2001)−1.6325Faxai (2007)−1.8752Winnie (1997)−1.63

Xangsane (2000)−2.0838Forrest (1986)−1.7512Stella (1998)−2.0839Kinna (1991)−1.7513Choi-wan (2009)−2.0840Irma (1981)−1.7414Vanessa (1984)−2.0641Marge (1983)−1.7315Elsie (1992)−2.0642Gay (1981)−1.73

Orchid (1980)−2.3133Cecil (1993)−1.767Nanmadol (2004)−2.1834Judy (1982)−1.768Rammasun (2008)−2.1735Irving (1979)−1.769Mireille (1991)−2.1536Owen (1979)−1.7510Songda (2004)−2.1337Flo (1990)−1.75

1Melor (2009)−2.5828Chaba (2004)−1.832Oscar (1995)−2.5729Colleen (1989)−1.823Hunt (1992)−2.3630Mac (1982)−1.794Haishen (2002)−2.3531Gordon (1982)−1.785Elsie (1981)−2.3232Megi (2004)−1.77

Schematic representation of upper-tropospheric ridge amplification and jet streak intensification associated with divergent TC outflow impinging upon an upper-tropospheric jet stream

54 recurving WNP TCs associated with strong TC–jet stream interactions

Recurvature-relative composite Hovmöller diagram

meridional wind anomaly (m s−1),

the asymmetry parameter from the Hart (2003) cyclone phase space2 is calculated from reanalysis data. This parameter provides a measure of the thermal asymmetry across the cyclone and has been used to objectively identify the onset of transition. As in Hart (2003), the onset of transition is defined as when the asymmetry parameter exceeds 10 m and is hereafter referred to as t = 0

Anomalies are defined as deviations from a moving-average climatology, meaning that every day of the year has a unique climatology, defined as the average of all daily fields within 14 days of the day of interest during the 32-yr period. This method of computing the climatology has the advantage of producing a smooth climatology from one day to the next.

a sceptical attitude to the widespread view that we can learn about causal processes by constructingDAG models of observational data

For a hypothetical conservative tracer,theLagrangian rate of change is identically equal tozero, and the Eulerian rate of change is

will look the same in any coordinate system

there is a simple geometrical way to calculate a⋅b\FLPa\cdot\FLPb, without having to calculate the components of a\FLPa and b\FLPb: a⋅b\FLPa\cdot\FLPb is the product of the length of a\FLPa and the length of b\FLPb times the cosine of the angle between them

Let us now define a new thing, which we call a⋅a\FLPa\cdot\FLPa. This is not a vector, but a scalar; it is a number that is the same in all coordinate systems, and it is defined to be the sum of the squares of the three components of the vector

conditional probability: P ( X | Y ) {\displaystyle P(X|Y)} , reads "the probability of X given Y"

A set is a gathering together into a whole of definite, distinct objects of our perception [Anschauung] or of our thought—which are called elements of the set.

Let us ask, “What is the meaning of the physical laws of Newton, which we write as F=maF=ma? What is the meaning of force, mass, and acceleration?” Well, we can intuitively sense the meaning of mass, and we can define acceleration if we know the meaning of position and time. We shall not discuss those meanings, but shall concentrate on the new concept of force. The answer is equally simple: “If a body is accelerating, then there is a force on it.” That is what Newton’s laws say, so the most precise and beautiful definition of force imaginable might simply be to say that force is the mass of an object times the acceleration. Suppose we have a law which says that the conservation of momentum is valid if the sum of all the external forces is zero; then the question arises, “What does it mean, that the sum of all the external forces is zero?” A pleasant way to define that statement would be: “When the total momentum is a constant, then the sum of the external forces is zero.” There must be something wrong with that, because it is just not saying anything new. If we have discovered a fundamental law, which asserts that the force is equal to the mass times the acceleration, and then define the force to be the mass times the acceleration, we have found out nothing.

The word "frequentist" is especially tricky. To philosophers it refers to a particular theory of physical probability, one that has more or less been abandoned. To scientists, on the other hand, "frequentist probability" is just another name for physical (or objective) probability. Those who promote Bayesian inference view "frequentist statistics" as an approach to statistical inference that recognises only physical probabilities.