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  • Author or Editor: J. C. Ma x
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Z. Su
,
W. Timmermans
,
Y. Zeng
,
J. Schulz
,
V. O. John
,
R. A. Roebeling
,
P. Poli
,
D. Tan
,
F. Kaspar
,
A. K. Kaiser-Weiss
,
E. Swinnen
,
C. Toté
,
H. Gregow
,
T. Manninen
,
A. Riihelä
,
J.-C. Calvet
,
Y. Ma
, and
J. Wen

Abstract

The Coordinating Earth Observation Data Validation for Reanalysis for Climate Services project (CORE-CLIMAX) aimed to substantiate how Copernicus observations and products can contribute to climate change analyses. CORE-CLIMAX assessed the European capability to provide climate data records (CDRs) of essential climate variables (ECVs), prepared a structured process to derive CDRs, developed a harmonized approach for validating essential climate variable CDRs, identified the integration of CDRs into the reanalysis chain, and formulated a process to compare the results of different reanalysis techniques. With respect to the Copernicus Climate Change Service (C3S), the systematic application and further development of the CORE-CLIMAX system maturity matrix (SMM) and the spinoff application performance metric (APM) were strongly endorsed to be involved in future implementations of C3S. We concluded that many of the current CDRs are not yet sufficiently mature to be used in reanalysis or applied in climate studies. Thus, the production of consistent high-resolution data records remains a challenge that needs more research urgently. Extending ECVs to close climate cycle budgets (e.g., essential water variables) is a next step linking CDRs to sectoral applications.

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K.-M. Lau
,
V. Ramanathan
,
G.-X. Wu
,
Z. Li
,
S. C. Tsay
,
C. Hsu
,
R. Sikka
,
B. Holben
,
D. Lu
,
G. Tartari
,
M. Chin
,
P. Koudelova
,
H. Chen
,
Y. Ma
,
J. Huang
,
K. Taniguchi
, and
R. Zhang

Aerosol- and moonsoon-related droughts and floods are two of the most serious environmental hazards confronting more than 60% of the population of the world living in the Asian monsoon countries. In recent years, thanks to improved satellite and in situ observations, and better models, great strides have been made in aerosol and monsoon research, respectively. There is now a growing body of evidence suggesting that interaction of aerosol forcing with monsoon dynamics may alter the redistribution of energy in the atmosphere and at the Earth s surface, thereby influencing monsoon water cycle and climate. In this article, the authors describe the scientific rationale and challenges for an integrated approach to study the interactions between aerosol and monsoon water cycle dynamics. A Joint Aerosol-Monsoon Experiment (JAMEX) is proposed for 2007–11, with enhanced observations of the physical and chemical properties, sources and sinks, and long-range transport of aerosols, in conjunction with meteorological and oceanographic observations in the Indo-Pacific continental and oceanic regions. JAMEX will leverage on coordination among many ongoing and planned national research programs on aerosols and monsoons in China, India, Japan, Nepal, Italy, and the United States, as well as international research programs of the World Climate Research Program (WCRP) and the World Meteorological Organization (WMO).

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Rob Cifelli
,
V. Chandrasekar
,
L. Herdman
,
D. D. Turner
,
A. B. White
,
T. I. Alcott
,
M. Anderson
,
P. Barnard
,
S. K. Biswas
,
M. Boucher
,
J. Bytheway
,
H. Chen
,
H. Cutler
,
J. M. English
,
L. Erikson
,
F. Junyent
,
D. J. Gottas
,
J. Jasperse
,
L. E. Johnson
,
J. Krebs
,
J. van de Lindt
,
J. Kim
,
M. Leon
,
Y. Ma
,
M. Marquis
,
W. Moninger
,
G. Pratt
,
C. Radhakrishnan
,
M. Shields
,
J. Spaulding
,
B. Tehranirad
, and
R. Webb

Abstract

Advanced Quantitative Precipitation Information (AQPI) is a synergistic project that combines observations and models to improve monitoring and forecasts of precipitation, streamflow, and coastal flooding in the San Francisco Bay Area. As an experimental system, AQPI leverages more than a decade of research, innovation, and implementation of a statewide, state-of-the-art network of observations, and development of the next generation of weather and coastal forecast models. AQPI was developed as a prototype in response to requests from the water management community for improved information on precipitation, riverine, and coastal conditions to inform their decision-making processes. Observation of precipitation in the complex Bay Area landscape of California’s coastal mountain ranges is known to be a challenging problem. But, with new advanced radar network techniques, AQPI is helping fill an important observational gap for this highly populated and vulnerable metropolitan area. The prototype AQPI system consists of improved weather radar data for precipitation estimation; additional surface measurements of precipitation, streamflow, and soil moisture; and a suite of integrated forecast modeling systems to improve situational awareness about current and future water conditions from sky to sea. Together these tools will help improve emergency preparedness and public response to prevent loss of life and destruction of property during extreme storms accompanied by heavy precipitation and high coastal water levels—especially high-moisture laden atmospheric rivers. The Bay Area AQPI system could potentially be replicated in other urban regions in California, the United States, and worldwide.

Open access
David C. Fritts
,
Ronald B. Smith
,
Michael J. Taylor
,
James D. Doyle
,
Stephen D. Eckermann
,
Andreas Dörnbrack
,
Markus Rapp
,
Bifford P. Williams
,
P.-Dominique Pautet
,
Katrina Bossert
,
Neal R. Criddle
,
Carolyn A. Reynolds
,
P. Alex Reinecke
,
Michael Uddstrom
,
Michael J. Revell
,
Richard Turner
,
Bernd Kaifler
,
Johannes S. Wagner
,
Tyler Mixa
,
Christopher G. Kruse
,
Alison D. Nugent
,
Campbell D. Watson
,
Sonja Gisinger
,
Steven M. Smith
,
Ruth S. Lieberman
,
Brian Laughman
,
James J. Moore
,
William O. Brown
,
Julie A. Haggerty
,
Alison Rockwell
,
Gregory J. Stossmeister
,
Steven F. Williams
,
Gonzalo Hernandez
,
Damian J. Murphy
,
Andrew R. Klekociuk
,
Iain M. Reid
, and
Jun Ma

Abstract

The Deep Propagating Gravity Wave Experiment (DEEPWAVE) was designed to quantify gravity wave (GW) dynamics and effects from orographic and other sources to regions of dissipation at high altitudes. The core DEEPWAVE field phase took place from May through July 2014 using a comprehensive suite of airborne and ground-based instruments providing measurements from Earth’s surface to ∼100 km. Austral winter was chosen to observe deep GW propagation to high altitudes. DEEPWAVE was based on South Island, New Zealand, to provide access to the New Zealand and Tasmanian “hotspots” of GW activity and additional GW sources over the Southern Ocean and Tasman Sea. To observe GWs up to ∼100 km, DEEPWAVE utilized three new instruments built specifically for the National Science Foundation (NSF)/National Center for Atmospheric Research (NCAR) Gulfstream V (GV): a Rayleigh lidar, a sodium resonance lidar, and an advanced mesosphere temperature mapper. These measurements were supplemented by in situ probes, dropsondes, and a microwave temperature profiler on the GV and by in situ probes and a Doppler lidar aboard the German DLR Falcon. Extensive ground-based instrumentation and radiosondes were deployed on South Island, Tasmania, and Southern Ocean islands. Deep orographic GWs were a primary target but multiple flights also observed deep GWs arising from deep convection, jet streams, and frontal systems. Highlights include the following: 1) strong orographic GW forcing accompanying strong cross-mountain flows, 2) strong high-altitude responses even when orographic forcing was weak, 3) large-scale GWs at high altitudes arising from jet stream sources, and 4) significant flight-level energy fluxes and often very large momentum fluxes at high altitudes.

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