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1.
Nature ; 571(7765): 393-397, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31316195

RESUMO

Existing estimates of sea surface temperatures (SSTs) indicate that, during the early twentieth century, the North Atlantic and northeast Pacific oceans warmed by twice the global average, whereas the northwest Pacific Ocean cooled by an amount equal to the global average1-4. Such a heterogeneous pattern suggests first-order contributions from regional variations in forcing or in ocean-atmosphere heat fluxes5,6. These older SST estimates are, however, derived from measurements of water temperatures in ship-board buckets, and must be corrected for substantial biases7-9. Here we show that correcting for offsets among groups of bucket measurements leads to SST variations that correlate better with nearby land temperatures and are more homogeneous in their pattern of warming. Offsets are identified by systematically comparing nearby SST observations among different groups10. Correcting for offsets in German measurements decreases warming rates in the North Atlantic, whereas correcting for Japanese measurement offsets leads to increased and more uniform warming in the North Pacific. Japanese measurement offsets in the 1930s primarily result from records having been truncated to whole degrees Celsius when the records were digitized in the 1960s. These findings underscore the fact that historical SST records reflect both physical and social dimensions in data collection, and suggest that further opportunities exist for improving the accuracy of historical SST records9,11.


Assuntos
Conjuntos de Dados como Assunto/normas , Aquecimento Global/estatística & dados numéricos , Água do Mar/análise , Temperatura , Ar/análise , Oceano Atlântico , Conjuntos de Dados como Assunto/história , Mapeamento Geográfico , Alemanha , Aquecimento Global/história , História do Século XX , Japão , Oceano Pacífico , Reprodutibilidade dos Testes
2.
Philos Trans A Math Phys Eng Sci ; 381(2249): 20220070, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37150199

RESUMO

The 5-year Ocean Regulation of Climate by Heat and Carbon Sequestration and Transports (ORCHESTRA) programme and its 1-year extension ENCORE (ENCORE is the National Capability ORCHESTRA Extension) was an approximately 11-million-pound programme involving seven UK research centres that finished in March 2022. The project sought to radically improve our ability to measure, understand and predict the exchange, storage and export of heat and carbon by the Southern Ocean. It achieved this through a series of milestone observational campaigns in combination with model development and analysis. Twelve cruises in the Weddell Sea and South Atlantic were undertaken, along with mooring, glider and profiler deployments and aircraft missions, all contributing to measurements of internal ocean and air-sea heat and carbon fluxes. Numerous forward and adjoint numerical experiments were developed and supported by the analysis of coupled climate models. The programme has resulted in over 100 peer-reviewed publications to date as well as significant impacts on climate assessments and policy and science coordination groups. Here, we summarize the research highlights of the programme and assess the progress achieved by ORCHESTRA/ENCORE and the questions it raises for the future. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.

3.
Sci Data ; 11(1): 953, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39214994

RESUMO

Accurate historical records of Earth's surface temperatures are central to climate research and policy development. Widely-used estimates based on instrumental measurements from land and sea are, however, not fully consistent at either global or regional scales. To address these challenges, we develop the Dynamically Consistent ENsemble of Temperature (DCENT), a 200-member ensemble of monthly surface temperature anomalies relative to the 1982-2014 climatology. Each DCENT member starts from 1850 and has a 5° × 5° resolution. DCENT leverages several updated or recently-developed approaches of data homogenization and bias adjustments: an optimized pairwise homogenization algorithm for identifying breakpoints in land surface air temperature records, a physics-informed inter-comparison method to adjust systematic offsets in sea-surface temperatures recorded by ships, and a coupled energy balance model to homogenize continental and marine records. Each approach was published individually, and this paper describes a combined approach and its application in developing a gridded analysis. A notable difference of DCENT relative to existing temperature estimates is a cooler baseline for 1850-1900 that implies greater historical warming.

4.
Ann Rev Mar Sci ; 13: 283-311, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33395347

RESUMO

Surface temperature documents our changing climate, and the marine record represents one of the longest widely distributed, observation-based estimates. Measurements of near-surface marine air temperature and sea-surface temperature have been recorded on platforms ranging from sailing ships to autonomous drifting buoys. The raw observations show an imprint of differing measurement methods and are sparse in certain periods and regions. This review describes how the real signal of global climate change can be determined from these sparse and noisy observations, including the quantification of measurement method-dependent biases and the reduction of spurious signals. Recent progress has come from analysis of the observations at increasing levels of granularity and from accounting for artifacts in the data that depend on platform types, measurement methods, and environmental conditions. Cutting across these effects are others caused by how the data were recorded, transcribed, and archived. These insights will be integrated into the next generation of global products quantified with validated estimates of uncertainty and the dependencies of its correlation structure. Further analysis of these records using improved data, metadata, and methods will certainly uncover more idiosyncrasies and new ways to improve the record.


Assuntos
Mudança Climática , Monitoramento Ambiental/métodos , Modelos Teóricos , Temperatura , Atividades Humanas , Cooperação Internacional , Navios
5.
Rev Urol ; 5 Suppl 3: S28-37, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-16985947

RESUMO

With increasing use of prostate-specific antigen as a screening tool, diagnosis of prostate cancer has undergone a stage migration toward early-stage disease. Although this has increased the proportion of men who are candidates for definitive, potentially curative therapy, it has also made clear the limitations of our current standard of care. Specifically, despite adequate local therapy, a significant proportion of men go on to develop progressive disease. Neoadjuvant systemic therapy is one approach that continues to be studied as a way to maximize cure rates in the setting of early-stage disease. This article reviews the current data regarding neoadjuvant therapy, both hormonal and chemotherapy, and discusses which men are appropriate candidates for this option.

6.
Curr Opin Urol ; 13(2): 123-31, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12584472

RESUMO

PURPOSE OF REVIEW: With the advent of prostate-specific antigen, stage migration has resulted in a shift towards early-stage prostate cancer at diagnosis. Although radical prostatectomy and radical radiotherapy can be curative in organ-confined disease, there remains a significant proportion of early-stage patients who go on to develop progressive, incurable disease. This review will highlight developments in the identification of high-risk patients, and summarize the results of investigations of adjuvant chemotherapy in this setting. RECENT FINDINGS: The ability to identify patients at high risk of developing progressive disease is improving. Both preoperative and postoperative variables, as well as newer radiographic and molecular tools, can identify at-risk patients who may benefit from adjuvant therapy. Coupled with developments in chemotherapeutic agents for prostate cancer, this provides the rationale for investigating chemotherapy in this setting. Unfortunately, to date, reported trials involving adjuvant chemotherapy in prostate cancer are few, and generally involve small numbers of patients. Some of the studies confirm that certain populations of patients, such as those with node-positive disease, may benefit from systemic therapy. Definitive data, however, will be derived from ongoing randomized trials investigating adjuvant chemotherapy. SUMMARY: Although definitive data regarding systemic chemotherapy in adjuvant therapy are scarce, the results of the available studies, and the increasing accuracy in delineating the population at risk, have laid the foundation for future and ongoing studies in this area.


Assuntos
Neoplasias da Próstata/tratamento farmacológico , Biomarcadores Tumorais/análise , Quimioterapia Adjuvante , Humanos , Masculino , Terapia Neoadjuvante , Neoplasias da Próstata/diagnóstico , Medição de Risco , Fatores de Risco
7.
Urology ; 62 Suppl 1: 134-40, 2003 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-14747051

RESUMO

Hormone-refractory prostate cancer (HRPC) encompasses a wide spectrum of patients, including patients with prostate-specific antigen (PSA)--only disease, those with increasing PSA levels yet stable metastatic disease, and those with increasing PSA levels and objective evidence of progressive metastases. Unfortunately, with the historical lack of effective therapy in this population, the oncologist is faced with few data with which to make difficult clinical decisions. Although our understanding of the biology of androgen independence continues to improve, and our fund of potential therapeutic agents has widened, multiple trial-specific and patient-specific obstacles have contributed to the difficulty in demonstrating clear benefit to therapy. Herein, we will review the biology of androgen-independent prostate cancer, the historical impediments to clinical trials in this population, and the reasons to treat, or not to treat, the patient with HRPC.


Assuntos
Adenocarcinoma/terapia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Próstata/terapia , Terapia de Salvação , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Biomarcadores , Administração de Caso , Ensaios Clínicos como Assunto/métodos , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Futilidade Médica , Proteínas de Neoplasias/sangue , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
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