Climate-mode initialization for decadal climate predictions

Abstract In the context of decadal climate predictions, a climate-mode initialization method is being tested by which ocean ORAS4 reanalysis is projected onto dominant modes of variability of the Earth System Model from the Max Planck Institute for Meteorology (MPI-ESM). The method aims to improve the prediction skill of the model by filtering out dynamically unbalanced noise during the initialization step. Used climate modes are calculated as statistical 3-D modes based on the bivariate empirical orthogonal function (EOF) analysis applied to temperature and salinity anomalies from an ensemble of historical simulations from the MPI-ESM. The climate-mode initialization method shows improved surface temperature skill, particularly over the tropical Pacific Ocean at seasonal-to-interannual timescales associated with the improved zonal momentum balance. There, the new initialization somewhat outperforms the surface temperature skill of the anomaly initialization also for lead years 2–5. In other parts of the world ocean, both initialization methods currently are equivalent in skill. However, only 44% of variance in the original ORAS4 reconstruction remains after the projection on model modes, suggesting that the ORAS4 modes are not fully compatible with the model modes. Moreover, we cannot dismiss the possibility that model modes are not sufficiently sampled with the data set underlying the EOF analysis. The full potential of the climate-mode initialization method for future decadal prediction systems therefore still needs to be quantified based on improved modal representation.

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An Evaluation of Rotated EOF Analysis and Its Application to Tropical Pacific SST Variability

Journal of Climate ◽

10.1175/jcli-d-11-00663.1 ◽

2012 ◽

Vol 25 (15) ◽

pp. 5361-5373 ◽

Cited By ~ 72

Author(s):

Tao Lian ◽

Dake Chen

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Tropical Pacific ◽

Sea Surface ◽

Eof Analysis ◽

Cooling Mode ◽

Modes Of Variability ◽

Sst Variability ◽

Space Reduction ◽

The Tropical Pacific

Abstract As an effective eigen method for phenomenon identification and space reduction, empirical orthogonal function (EOF) analysis is widely used in climate research. However, because of its orthorgonality constraint, EOF analysis has a tendency to produce unphysical modes. Previous studies have shown that the drawbacks of EOF analysis could be partly alleviated by rotated EOF (REOF) analysis, but such studies are always based on specific cases. This paper provides a thorough statistical evaluation of REOF analysis by comparing its ability with that of EOF analysis in reproducing a large number of randomly selected stationary modes of variability. The synthetic experiments indicate that REOF analysis is overwhelmingly a better choice in terms of accuracy and effectiveness, especially for picking up localized patterns. When applied to the tropical Pacific sea surface temperature variability, REOF and EOF analyses show obvious discrepancies, with the former making much better physical sense. This challenges the validity of the so-called sea surface temperature cooling mode and the spatial structure of “El Niño Modoki,” both of which are recently identified by EOF analysis. At any rate, one has to be cautious when claiming new discoveries of climate modes based on EOF analysis alone.

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Skillful Dynamical-Statistical Predictions of European Summer Temperature

10.5194/egusphere-egu21-10788 ◽

2021 ◽

Author(s):

Juliette Mignot ◽

Leonard Borchert ◽

Vimal Koul ◽

Björn Mayer ◽

Matthew Menary ◽

...

Keyword(s):

Surface Temperature ◽

North Atlantic ◽

Spectral Band ◽

Summer Temperature ◽

Statistical Prediction ◽

Climate Projections ◽

Decadal Prediction ◽

Data Set ◽

Temperature Variations ◽

Decadal Climate

While decadal North Atlantic sea surface temperature (SST) variations are generally predictable, prediction skill of surface temperature over Europe is much more limited. We invoke here observed links of decadal European summer temperature variations to North Atlantic SST changes in the preceding months to produce skillful decadal predictions of European summer temperature variations.We analyze the ERA5 reanalysis data set to re-assess the observed influence of North Atlantic SST on European summer temperature for the period 1960-2020. To facilitate possible merging activities of initialized decadal prediction simulations and climate projections in the future, we examine predictions for the target regions Northern Europe (NEU), Central Europe (CEU) and Mediterranean (MED) as are defined as the SREX regions for IPCC Assessment Report 5. Summer (June-July-August: JJA) temperature in NEU shows significant co-variability in a decadal spectral band with MAM SST in the Western North Atlantic (WNA), while JJA CEU temperature shows the same with JJA SST in that region. JJA temperature in the MED region shows significant decadal co-variability with the annual mean AMV index. SVD analysis illustrates that an atmospheric Rossby wave train connects North Atlantic SST to European summer temperature changes.Dynamical retrospective forecasts from a suite of decadal prediction systems from the Coupled Model Intercomparison Project Phase 6 Decadal Climate Prediction Project are tested for their agreement with observations for the period 1960-2020. Dynamical predictions of JJA temperature in NEU, CEU and MED are mostly not skillful at lead years 1-10 in the CMIP6 simulations. Most models do, however, show skill in the SST regions that are connected to these summer temperature variations, identified above. We use these SST predictions to drive a simple statistical model that rescales the variance of the SST predictions according to observed SAT variance in the target region. This dynamical-statistical prediction is shown to be skillful at lead years 1-10 for summer temperature in the SREX regions. This skill, however, relies on the skill of the models in predicting the respective SST index. Our work therefore indicates a promising avenue to produce skillful decadal climate predictions over land based on skillful predictions of the ocean.

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Analysis of variability and long-term trends of sea surface temperature over the China Seas derived from a newly merged regional data set

Climate Research ◽

10.3354/cr01471 ◽

2017 ◽

Vol 73 (3) ◽

pp. 217-231 ◽

Cited By ~ 2

Author(s):

Y Li ◽

L Mu ◽

Y Liu ◽

G Wang ◽

D Zhang ◽

...

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Sea Surface ◽

China Seas ◽

Regional Data ◽

Data Set ◽

Long Term Trends ◽

The China Seas

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EXTREME VALUES OF SEA SURFACE TEMPERATURE ASSOCIATED WITH LONG-PERIOD PHENOMENA OCCURRED DURING 1960-2015 IN THE COLOMBIAN PACIFIC OCEAN

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.31519/conferencearticle_5b1b943a9e4336.75393991 ◽

2017 ◽

Author(s):

Diaz Juan Navia ◽

Bolaños Nancy Villegas ◽

Igor Malikov ◽

...

Keyword(s):

Time Series ◽

Pacific Ocean ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Extreme Values ◽

Sea Surface ◽

Absolute Maximum ◽

Data Set ◽

Arctic Oscillation Index ◽

Colombian Pacific

Sea Surface Temperature Anomalies (SSTA), in four coastal hydrographic stations of Colombian Pacific Ocean, were analyzed. The selected hydrographic stations were: Tumaco (1°48'N-78°45'W), Gorgona island (2°58'N-78°11'W), Solano Bay (6°13'N-77°24'W) and Malpelo island (4°0'N-81°36'W). SSTA time series for 1960-2015 were calculated from monthly Sea Surface Temperature obtained from International Comprehensive Ocean Atmosphere Data Set (ICOADS). SSTA time series, Oceanic Nino Index (ONI), Pacific Decadal Oscillation index (PDO), Arctic Oscillation index (AO) and sunspots number (associated to solar activity), were compared. It was found that the SSTA absolute minimum has occurred in Tumaco (-3.93°C) in March 2009, in Gorgona (-3.71°C) in October 2007, in Solano Bay (-4.23°C) in April 2014 and Malpelo (-4.21°C) in December 2005. The SSTA absolute maximum was observed in Tumaco (3.45°C) in January 2002, in Gorgona (5.01°C) in July 1978, in Solano Bay (5.27°C) in March 1998 and Malpelo (3.64°C) in July 2015. A high correlation between SST and ONI in large part of study period, followed by a good correlation with PDO, was identified. The AO and SSTA have showed an inverse relationship in some periods. Solar Cycle has showed to be a modulator of behavior of SSTA in the selected stations. It was determined that extreme values of SST are related to the analyzed large scale oscillations.

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Numerical simulations of spreading of the Persian Gulf outflow into the Oman Sea

Ocean Science ◽

10.5194/os-6-887-2010 ◽

2010 ◽

Vol 6 (4) ◽

pp. 887-900 ◽

Cited By ~ 15

Author(s):

M. Ezam ◽

A. A. Bidokhti ◽

A. H. Javid

Keyword(s):

Persian Gulf ◽

Bottom Topography ◽

World Ocean ◽

Monthly Precipitation ◽

Boundary Current ◽

Surface Salinity ◽

Data Set ◽

Open Boundaries ◽

The Mean ◽

The Persian Gulf

Abstract. A three dimensional numerical model namely POM (Princeton Ocean Model) and observational data are used to study the Persian Gulf outflow structure and its spreading pathways during 1992. In the model, the monthly wind speed data were taken from ICOADS (International Comprehensive Ocean-Atmosphere Data Set) and the monthly SST (sea surface temperatures) were taken from AVHRR (Advanced Very High Resolution Radiometer) with the addition of monthly net shortwave radiations from NCEP (National Center for Environmental Prediction). The mean monthly precipitation rates from NCEP data and the calculated evaporation rates are used to impose the surface salinity fluxes. At the open boundaries the temperature and salinity were prescribed from the mean monthly climatological values from WOA05 (World Ocean Atlas 2005). Also the four major components of the tide were prescribed at the open boundaries. The results show that the outflow mainly originates from two branches at different depths in the Persian Gulf. The permanent branch exists during the whole year deeper than 40 m along the Gulf axis and originates from the inner parts of the Persian Gulf. The other seasonal branch forms in the vicinity of the shallow southern coasts due to high evaporation rates during winter. Near the Strait of Hormuz the two branches join and form the main outflow source water. The results of simulations reveal that during the winter the outflow boundary current mainly detaches from the coast well before Ras Al Hamra Cape, however during summer the outflow seems to follow the coast even after this Cape. This is due to a higher density of the colder outflow that leads to more sinking near the coast in winter. Thus, the outflow moves to a deeper depth of about 500 m (for which some explanations are given) while the main part detaches and spreads at a depth of about 300 m. However in summer it all moves at a depth of about 200–250 m. During winter, the deeper, stronger and wider outflow is more affected by the steep topography, leading to separation from the coast. While during summer, the weaker and shallower outflow is less influenced by bottom topography and so continues along the boundary.

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Uji Akurasi Dataset Pasien Pasca Operasi Menggunakan Algoritma Naïve Bayes Menggunakan Weka Tools

JURIKOM (Jurnal Riset Komputer) ◽

10.30865/jurikom.v7i1.1761 ◽

2020 ◽

Vol 7 (1) ◽

pp. 134

Author(s):

Muhammad Rahmadi ◽

Fazriyanor Kaurie ◽

Tuti Susanti

Keyword(s):

Blood Pressure ◽

Surface Temperature ◽

Kansas City ◽

Medical Center ◽

Data Sets ◽

University Of Kansas ◽

Postoperative Patient ◽

Data Set ◽

University Of Missouri ◽

School Of Nursing

Postoperative patient data sets taken for testing of this data are sourced from the UCI repository on the website https://archive.ics.uci.edu/ml/datasets/Post-Operative+Patient. Based on the website address, the study was conducted by Sharon Summers, School of Nursing, University of Kansas, Medical Center, Kansas City, KS 66160 and Linda Woolery, School of Nursing, University of Missouri, Columbia, MO 6521. Number of attributes from this data set there are 8 and 1 class, the attributes in question include; L-CORE (patient's internal temperature in C), L-SURF (patient's surface temperature in C), L-O2 (oxygen saturation in%), L-BP (last measurement of blood pressure), SURF-STBL (stability of the patient's surface temperature ), CORE-STBL (stability of the patient), BP-STBL (stability of the patient's blood pressure), COMFORT (perceived comfort of the patient at discharge, measured as an integer between 0 and 20) and ADM-DECS decision class / patient exit decision with information (I = patient sent to intensive care unit, S = patient ready to go home, A = patient sent to general hospital floor).

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Variations in Winter Surface Temperature of the Purog Kangri Ice Field, Qinghai–Tibetan Plateau, 2001–2018, Using MODIS Data

Remote Sensing ◽

10.3390/rs12071133 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1133

Author(s):

Yufan Qie ◽

Ninglian Wang ◽

Yuwei Wu ◽

An’an Chen

Keyword(s):

Tibetan Plateau ◽

Surface Temperature ◽

Land Surface ◽

Remote Sensing Data ◽

Warming Trend ◽

Data Set ◽

Moderate Resolution ◽

Ice Field ◽

Moderate Resolution Imaging Spectroradiometer ◽

Meteorological Observations

In the context of global warming, the land surface temperature (LST) from remote sensing data is one of the most useful indicators to directly quantify the degree of climate warming in high-altitude mountainous areas where meteorological observations are sparse. Using the daily Moderate Resolution Imaging Spectroradiometer (MODIS) LST product (MOD11A1 V6) after eliminating pixels that might be contaminated by clouds, this paper analyzes temporal and spatial variations in the mean LST on the Purog Kangri ice field, Qinghai–Tibetan Plateau, in winter from 2001 to 2018. There was a large increasing trend in LST (0.116 ± 0.05 °C·a−1) on the Purog Kangri ice field during December, while there was no evident LST rising trend in January and February. In December, both the significantly decreased albedo (−0.002 a−1, based on the MOD10A1 V6 albedo product) on the ice field surface and the significantly increased number of clear days (0.322 d·a−1) may be the main reason for the significant warming trend in the ice field. In addition, although the two highest LST of December were observed in 2017 and 2018, a longer data set is needed to determine whether this is an anomaly or a hint of a warmer phase of the Purog Kangri ice field in December.

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A change in granularity: measure space utilization through smart technologies

Facilities ◽

10.1108/f-08-2019-0093 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Chiara Tagliaro ◽

Yaoyi Zhou ◽

Ying Hua

Keyword(s):

Smart Sensors ◽

Full Potential ◽

Calculation Methods ◽

Space Utilization ◽

Data Set ◽

Content Type ◽

Office Space ◽

Challenges And Opportunities ◽

Utilization Data ◽

Smart Technologies

Purpose Workplace space utilization data reveals patterns of space usage, the occupants’ presence and mobility within the office building. Nowadays, emerging technology such as smart sensors and devices can revolutionize the measurement of space utilization data, which is originally dominated by human observers with paper and pencil. However, these novel instruments are often used in an old fashion, which restricts the exploitation of their full potential. This study aims to shed new light on the benefits and limits of using smart technology in measuring space utilization data and discusses the challenges and opportunities in analyzing the data measured by smart sensors. Design/methodology/approach First, the literature regarding common methods and previous studies about office space utilization measurement was reviewed. Then, a data set consisting of space utilization data collected through Passive Infra-Red sensors for 35 meeting rooms in a bank building was carefully evaluated. Finally, the space utilization results based on methods calculated in two different granularities were compared. Findings The number of occupied hours calculated at an hour level was 1.32-hour larger than that calculated at a minute level. As both results show the concept of space utilization, which was the amount of time that the space was occupied, this paper revealed a gap between the two space utilization calculation methods and further discussed the issues and challenges for future space utilization data analysis and benchmarking. Originality/value To the best of the authors’ knowledge, this is the first study critically addressing office space utilization issues by comparing calculation methods in different granularity.

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PP32 Electronic records in ambulances – an observational study (ERA)

Emergency Medicine Journal ◽

10.1136/emermed-2019-999abs.32 ◽

2019 ◽

Vol 36 (10) ◽

pp. e14-e14

Author(s):

Alison Porter ◽

Sarah Black ◽

Jeremy Dale ◽

Robert Harris-Mayes ◽

Robin Lawrenson ◽

...

Keyword(s):

National Policy ◽

Patient Data ◽

Information Support ◽

Electronic Records ◽

Health Economy ◽

Local Health ◽

Full Potential ◽

Data Set ◽

Emergency Ambulance ◽

The Uk

BackgroundThe introduction of information technology (IT) in emergency ambulance services to electronically capture, interpret and store patient data can support out of hospital care. Although electronic health records (EHR) in ambulances and other digital technology are encouraged by national policy across the UK, there is considerable variation across services in terms of implementation. We aimed to understand how electronic records can be most effectively implemented in a pre-hospital context, in order to support a safe and effective shift from acute to community-based care.MethodsWe conducted a mixed-methods study with four work packages (WPs): a rapid literature review, a telephone survey of all 13 freestanding UK ambulance services, detailed case studies in four selected sites, and a knowledge sharing workshop.ResultsWe found considerable variation in hardware and software. Services were in a state of constant change, with services transitioning from one system to another, reverting to paper, or upgrading. Ambulance clinicians were dealing with partial or unclear information, which may not fit comfortably with the EHR. Clinicians continued to use indirect data input approaches such as first writing on a glove. The primary function of EHR in all services seemed to be as a store for patient data. There was, as yet, limited evidence of their full potential being realised to transfer information, support decision making or change patient care.ConclusionsRealising the full benefits of EHR requires engagement with other parts of the local health economy, dealing with the challenges of interoperability. Clinicians and data managers are likely to want very different things from a data set, and need to be presented with only the information that they need.

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