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  • Author or Editor: C. E. Anderson x
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Rebecca E. Morss
,
Julie L. Demuth
,
Heather Lazrus
,
Leysia Palen
,
C. Michael Barton
,
Christopher A. Davis
,
Chris Snyder
,
Olga V. Wilhelmi
,
Kenneth M. Anderson
,
David A. Ahijevych
,
Jennings Anderson
,
Melissa Bica
,
Kathryn R. Fossell
,
Jennifer Henderson
,
Marina Kogan
,
Kevin Stowe
, and
Joshua Watts

Abstract

During the last few decades, scientific capabilities for understanding and predicting weather and climate risks have advanced rapidly. At the same time, technological advances, such as the Internet, mobile devices, and social media, are transforming how people exchange and interact with information. In this modern information environment, risk communication, interpretation, and decision-making are rapidly evolving processes that intersect across space, time, and society. Instead of a linear or iterative process in which individual members of the public assess and respond to distinct pieces of weather forecast or warning information, this article conceives of weather prediction, communication, and decision-making as an interconnected dynamic system. In this expanded framework, information and uncertainty evolve in conjunction with people’s risk perceptions, vulnerabilities, and decisions as a hazardous weather threat approaches; these processes are intertwined with evolving social interactions in the physical and digital worlds. Along with the framework, the article presents two interdisciplinary research approaches for advancing the understanding of this complex system and the processes within it: analysis of social media streams and computational natural–human system modeling. Examples from ongoing research are used to demonstrate these approaches and illustrate the types of new insights they can reveal. This expanded perspective together with research approaches, such as those introduced, can help researchers and practitioners understand and improve the creation and communication of information in atmospheric science and other fields.

Open access
J. Shukla
,
J. Anderson
,
D. Baumhefner
,
C. Brankovic
,
Y. Chang
,
E. Kalnay
,
L. Marx
,
T. Palmer
,
D. Paolino
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J. Ploshay
,
S. Schubert
,
D. Straus
,
M. Suarez
, and
J. Tribbia

Dynamical Seasonal Prediction (DSP) is an informally coordinated multi-institution research project to investigate the predictability of seasonal mean atmospheric circulation and rainfall. The basic idea is to test the feasibility of extending the technology of routine numerical weather prediction beyond the inherent limit of deterministic predictability of weather to produce numerical climate predictions using state-of-the-art global atmospheric models. Atmospheric general circulation models (AGCMs) either forced by predicted sea surface temperature (SST) or as part of a coupled forecast system have shown in the past that certain regions of the extratropics, in particular, the Pacific–North America (PNA) region during Northern Hemisphere winter, can be predicted with significant skill especially during years of large tropical SST anomalies. However, there is still a great deal of uncertainty about how much the details of various AGCMs impact conclusions about extratropical seasonal prediction and predictability.

DSP is designed to compare seasonal simulation and prediction results from five state-of-the-art U.S. modeling groups (NCAR, COLA, GSFC, GFDL, NCEP) in order to assess which aspects of the results are robust and which are model dependent. The initial emphasis is on the predictability of seasonal anomalies over the PNA region. This paper also includes results from the ECMWF model, and historical forecast skill over both the PNA region and the European region is presented for all six models.

It is found that with specified SST boundary conditions, all models show that the winter season mean circulation anomalies over the Pacific–North American region are highly predictable during years of large tropical sea surface temperature anomalies. The influence of large anomalous boundary conditions is so strong and so reproducible that the seasonal mean forecasts can be given with a high degree of confidence. However, the degree of reproducibility is highly variable from one model to the other, and quantities such as the PNA region signal to noise ratio are found to vary significantly between the different AGCMs. It would not be possible to make reliable estimates of predictability of the seasonal mean atmosphere circulation unless causes for such large differences among models are understood.

Full access
Wayman E. Baker
,
George D. Emmitt
,
Franklin Robertson
,
Robert M. Atlas
,
John E. Molinari
,
David A. Bowdle
,
Jan Paegle
,
R. Michael Hardesty
,
Robert T. Menzies
,
T. N. Krishnamurti
,
Robert A. Brown
,
Madison J. Post
,
John R. Anderson
,
Andrew C. Lorenc
, and
James McElroy

The deployment of a space-based Doppler lidar would provide information that is fundamental to advancing the understanding and prediction of weather and climate.

This paper reviews the concepts of wind measurement by Doppler lidar, highlights the results of some observing system simulation experiments with lidar winds, and discusses the important advances in earth system science anticipated with lidar winds.

Observing system simulation experiments, conducted using two different general circulation models, have shown 1) that there is a significant improvement in the forecast accuracy over the Southern Hemisphere and tropical oceans resulting from the assimilation of simulated satellite wind data, and 2) that wind data are significantly more effective than temperature or moisture data in controlling analysis error. Because accurate wind observations are currently almost entirely unavailable for the vast majority of tropical cyclones worldwide, lidar winds have the potential to substantially improve tropical cyclone forecasts. Similarly, to improve water vapor flux divergence calculations, a direct measure of the ageostrophic wind is needed since the present level of uncertainty cannot be reduced with better temperature and moisture soundings alone.

Full access
J. Boutin
,
Y. Chao
,
W. E. Asher
,
T. Delcroix
,
R. Drucker
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K. Drushka
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N. Kolodziejczyk
,
T. Lee
,
N. Reul
,
G. Reverdin
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J. Schanze
,
A. Soloviev
,
L. Yu
,
J. Anderson
,
L. Brucker
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E. Dinnat
,
A. Santos-Garcia
,
W. L. Jones
,
C. Maes
,
T. Meissner
,
W. Tang
,
N. Vinogradova
, and
B. Ward

Abstract

Remote sensing of salinity using satellite-mounted microwave radiometers provides new perspectives for studying ocean dynamics and the global hydrological cycle. Calibration and validation of these measurements is challenging because satellite and in situ methods measure salinity differently. Microwave radiometers measure the salinity in the top few centimeters of the ocean, whereas most in situ observations are reported below a depth of a few meters. Additionally, satellites measure salinity as a spatial average over an area of about 100 × 100 km2. In contrast, in situ sensors provide pointwise measurements at the location of the sensor. Thus, the presence of vertical gradients in, and horizontal variability of, sea surface salinity complicates comparison of satellite and in situ measurements. This paper synthesizes present knowledge of the magnitude and the processes that contribute to the formation and evolution of vertical and horizontal variability in near-surface salinity. Rainfall, freshwater plumes, and evaporation can generate vertical gradients of salinity, and in some cases these gradients can be large enough to affect validation of satellite measurements. Similarly, mesoscale to submesoscale processes can lead to horizontal variability that can also affect comparisons of satellite data to in situ data. Comparisons between satellite and in situ salinity measurements must take into account both vertical stratification and horizontal variability.

Full access
L. L. Pan
,
E. L. Atlas
,
R. J. Salawitch
,
S. B. Honomichl
,
J. F. Bresch
,
W. J. Randel
,
E. C. Apel
,
R. S. Hornbrook
,
A. J. Weinheimer
,
D. C. Anderson
,
S. J. Andrews
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S. Baidar
,
S. P. Beaton
,
T. L. Campos
,
L. J. Carpenter
,
D. Chen
,
B. Dix
,
V. Donets
,
S. R. Hall
,
T. F. Hanisco
,
C. R. Homeyer
,
L. G. Huey
,
J. B. Jensen
,
L. Kaser
,
D. E. Kinnison
,
T. K. Koenig
,
J.-F. Lamarque
,
C. Liu
,
J. Luo
,
Z. J. Luo
,
D. D. Montzka
,
J. M. Nicely
,
R. B. Pierce
,
D. D. Riemer
,
T. Robinson
,
P. Romashkin
,
A. Saiz-Lopez
,
S. Schauffler
,
O. Shieh
,
M. H. Stell
,
K. Ullmann
,
G. Vaughan
,
R. Volkamer
, and
G. Wolfe

Abstract

The Convective Transport of Active Species in the Tropics (CONTRAST) experiment was conducted from Guam (13.5°N, 144.8°E) during January–February 2014. Using the NSF/NCAR Gulfstream V research aircraft, the experiment investigated the photochemical environment over the tropical western Pacific (TWP) warm pool, a region of massive deep convection and the major pathway for air to enter the stratosphere during Northern Hemisphere (NH) winter. The new observations provide a wealth of information for quantifying the influence of convection on the vertical distributions of active species. The airborne in situ measurements up to 15-km altitude fill a significant gap by characterizing the abundance and altitude variation of a wide suite of trace gases. These measurements, together with observations of dynamical and microphysical parameters, provide significant new data for constraining and evaluating global chemistry–climate models. Measurements include precursor and product gas species of reactive halogen compounds that impact ozone in the upper troposphere/lower stratosphere. High-accuracy, in situ measurements of ozone obtained during CONTRAST quantify ozone concentration profiles in the upper troposphere, where previous observations from balloonborne ozonesondes were often near or below the limit of detection. CONTRAST was one of the three coordinated experiments to observe the TWP during January–February 2014. Together, CONTRAST, Airborne Tropical Tropopause Experiment (ATTREX), and Coordinated Airborne Studies in the Tropics (CAST), using complementary capabilities of the three aircraft platforms as well as ground-based instrumentation, provide a comprehensive quantification of the regional distribution and vertical structure of natural and pollutant trace gases in the TWP during NH winter, from the oceanic boundary to the lower stratosphere.

Full access
Robert M. Rauber
,
Bjorn Stevens
,
Harry T. Ochs III
,
Charles Knight
,
B. A. Albrecht
,
A. M. Blyth
,
C. W. Fairall
,
J. B. Jensen
,
S. G. Lasher-Trapp
,
O. L. Mayol-Bracero
,
G. Vali
,
J. R. Anderson
,
B. A. Baker
,
A. R. Bandy
,
E. Burnet
,
J.-L. Brenguier
,
W. A. Brewer
,
P. R. A. Brown
,
R Chuang
,
W. R. Cotton
,
L. Di Girolamo
,
B. Geerts
,
H. Gerber
,
S. Göke
,
L. Gomes
,
B. G. Heikes
,
J. G. Hudson
,
P. Kollias
,
R. R Lawson
,
S. K. Krueger
,
D. H. Lenschow
,
L. Nuijens
,
D. W. O'Sullivan
,
R. A. Rilling
,
D. C. Rogers
,
A. P. Siebesma
,
E. Snodgrass
,
J. L. Stith
,
D. C. Thornton
,
S. Tucker
,
C. H. Twohy
, and
P. Zuidema

Shallow, maritime cumuli are ubiquitous over much of the tropical oceans, and characterizing their properties is important to understanding weather and climate. The Rain in Cumulus over the Ocean (RICO) field campaign, which took place during November 2004–January 2005 in the trades over the western Atlantic, emphasized measurements of processes related to the formation of rain in shallow cumuli, and how rain subsequently modifies the structure and ensemble statistics of trade wind clouds. Eight weeks of nearly continuous S-band polarimetric radar sampling, 57 flights from three heavily instrumented research aircraft, and a suite of ground- and ship-based instrumentation provided data on trade wind clouds with unprecedented resolution. Observational strategies employed during RICO capitalized on the advances in remote sensing and other instrumentation to provide insight into processes that span a range of scales and that lie at the heart of questions relating to the cause and effects of rain from shallow maritime cumuli.

Full access
Robert M. Rauber
,
Harry T. Ochs III
,
L. Di Girolamo
,
S. Göke
,
E. Snodgrass
,
Bjorn Stevens
,
Charles Knight
,
J. B. Jensen
,
D. H. Lenschow
,
R. A. Rilling
,
D. C. Rogers
,
J. L. Stith
,
B. A. Albrecht
,
P. Zuidema
,
A. M. Blyth
,
C. W. Fairall
,
W. A. Brewer
,
S. Tucker
,
S. G. Lasher-Trapp
,
O. L. Mayol-Bracero
,
G. Vali
,
B. Geerts
,
J. R. Anderson
,
B. A. Baker
,
R. P. Lawson
,
A. R. Bandy
,
D. C. Thornton
,
E. Burnet
,
J-L. Brenguier
,
L. Gomes
,
P. R. A. Brown
,
P. Chuang
,
W. R. Cotton
,
H. Gerber
,
B. G. Heikes
,
J. G. Hudson
,
P. Kollias
,
S. K. Krueger
,
L. Nuijens
,
D. W. O'Sullivan
,
A. P. Siebesma
, and
C. H. Twohy
Full access
Guy P. Brasseur
,
Mohan Gupta
,
Bruce E. Anderson
,
Sathya Balasubramanian
,
Steven Barrett
,
David Duda
,
Gregg Fleming
,
Piers M. Forster
,
Jan Fuglestvedt
,
Andrew Gettelman
,
Rangasayi N. Halthore
,
S. Daniel Jacob
,
Mark Z. Jacobson
,
Arezoo Khodayari
,
Kuo-Nan Liou
,
Marianne T. Lund
,
Richard C. Miake-Lye
,
Patrick Minnis
,
Seth Olsen
,
Joyce E. Penner
,
Ronald Prinn
,
Ulrich Schumann
,
Henry B. Selkirk
,
Andrei Sokolov
,
Nadine Unger
,
Philip Wolfe
,
Hsi-Wu Wong
,
Donald W. Wuebbles
,
Bingqi Yi
,
Ping Yang
, and
Cheng Zhou

Abstract

Under the Federal Aviation Administration’s (FAA) Aviation Climate Change Research Initiative (ACCRI), non-CO2 climatic impacts of commercial aviation are assessed for current (2006) and for future (2050) baseline and mitigation scenarios. The effects of the non-CO2 aircraft emissions are examined using a number of advanced climate and atmospheric chemistry transport models. Radiative forcing (RF) estimates for individual forcing effects are provided as a range for comparison against those published in the literature. Preliminary results for selected RF components for 2050 scenarios indicate that a 2% increase in fuel efficiency and a decrease in NOx emissions due to advanced aircraft technologies and operational procedures, as well as the introduction of renewable alternative fuels, will significantly decrease future aviation climate impacts. In particular, the use of renewable fuels will further decrease RF associated with sulfate aerosol and black carbon. While this focused ACCRI program effort has yielded significant new knowledge, fundamental uncertainties remain in our understanding of aviation climate impacts. These include several chemical and physical processes associated with NOx–O3–CH4 interactions and the formation of aviation-produced contrails and the effects of aviation soot aerosols on cirrus clouds as well as on deriving a measure of change in temperature from RF for aviation non-CO2 climate impacts—an important metric that informs decision-making.

Full access
Bruce A. Wielicki
,
D. F. Young
,
M. G. Mlynczak
,
K. J. Thome
,
S. Leroy
,
J. Corliss
,
J. G. Anderson
,
C. O. Ao
,
R. Bantges
,
F. Best
,
K. Bowman
,
H. Brindley
,
J. J. Butler
,
W. Collins
,
J. A. Dykema
,
D. R. Doelling
,
D. R. Feldman
,
N. Fox
,
X. Huang
,
R. Holz
,
Y. Huang
,
Z. Jin
,
D. Jennings
,
D. G. Johnson
,
K. Jucks
,
S. Kato
,
D. B. Kirk-Davidoff
,
R. Knuteson
,
G. Kopp
,
D. P. Kratz
,
X. Liu
,
C. Lukashin
,
A. J. Mannucci
,
N. Phojanamongkolkij
,
P. Pilewskie
,
V. Ramaswamy
,
H. Revercomb
,
J. Rice
,
Y. Roberts
,
C. M. Roithmayr
,
F. Rose
,
S. Sandford
,
E. L. Shirley
,
Sr. W. L. Smith
,
B. Soden
,
P. W. Speth
,
W. Sun
,
P. C. Taylor
,
D. Tobin
, and
X. Xiong

The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission will provide a calibration laboratory in orbit for the purpose of accurately measuring and attributing climate change. CLARREO measurements establish new climate change benchmarks with high absolute radiometric accuracy and high statistical confidence across a wide range of essential climate variables. CLARREO's inherently high absolute accuracy will be verified and traceable on orbit to Système Internationale (SI) units. The benchmarks established by CLARREO will be critical for assessing changes in the Earth system and climate model predictive capabilities for decades into the future as society works to meet the challenge of optimizing strategies for mitigating and adapting to climate change. The CLARREO benchmarks are derived from measurements of the Earth's thermal infrared spectrum (5–50 μm), the spectrum of solar radiation reflected by the Earth and its atmosphere (320–2300 nm), and radio occultation refractivity from which accurate temperature profiles are derived. The mission has the ability to provide new spectral fingerprints of climate change, as well as to provide the first orbiting radiometer with accuracy sufficient to serve as the reference transfer standard for other space sensors, in essence serving as a “NIST [National Institute of Standards and Technology] in orbit.” CLARREO will greatly improve the accuracy and relevance of a wide range of space-borne instruments for decadal climate change. Finally, CLARREO has developed new metrics and methods for determining the accuracy requirements of climate observations for a wide range of climate variables and uncertainty sources. These methods should be useful for improving our understanding of observing requirements for most climate change observations.

Full access
William P. Kustas
,
Martha C. Anderson
,
Joseph G. Alfieri
,
Kyle Knipper
,
Alfonso Torres-Rua
,
Christopher K. Parry
,
Hector Nieto
,
Nurit Agam
,
William A. White
,
Feng Gao
,
Lynn McKee
,
John H. Prueger
,
Lawrence E. Hipps
,
Sebastian Los
,
Maria Mar Alsina
,
Luis Sanchez
,
Brent Sams
,
Nick Dokoozlian
,
Mac McKee
,
Scott Jones
,
Yun Yang
,
Tiffany G. Wilson
,
Fangni Lei
,
Andrew McElrone
,
Josh L. Heitman
,
Adam M. Howard
,
Kirk Post
,
Forrest Melton
, and
Christopher Hain

Abstract

Particularly in light of California’s recent multiyear drought, there is a critical need for accurate and timely evapotranspiration (ET) and crop stress information to ensure long-term sustainability of high-value crops. Providing this information requires the development of tools applicable across the continuum from subfield scales to improve water management within individual fields up to watershed and regional scales to assess water resources at county and state levels. High-value perennial crops (vineyards and orchards) are major water users, and growers will need better tools to improve water-use efficiency to remain economically viable and sustainable during periods of prolonged drought. To develop these tools, government, university, and industry partners are evaluating a multiscale remote sensing–based modeling system for application over vineyards. During the 2013–17 growing seasons, the Grape Remote Sensing Atmospheric Profile and Evapotranspiration eXperiment (GRAPEX) project has collected micrometeorological and biophysical data within adjacent pinot noir vineyards in the Central Valley of California. Additionally, each year ground, airborne, and satellite remote sensing data were collected during intensive observation periods (IOPs) representing different vine phenological stages. An overview of the measurements and some initial results regarding the impact of vine canopy architecture on modeling ET and plant stress are presented here. Refinements to the ET modeling system based on GRAPEX are being implemented initially at the field scale for validation and then will be integrated into the regional modeling toolkit for large area assessment.

Full access