A5041525018- Tree-ring climate responses
- Plant Water Relations and Carbon Dynamics
- Meteorological Phenomena and Simulations
- Geology and Paleoclimatology Research
- Galaxies: Formation, Evolution, Phenomena
- Advanced Numerical Methods in Computational Mathematics
- Computational Fluid Dynamics and Aerodynamics
- Stellar, planetary, and galactic studies
- Climate variability and models
- Astronomy and Astrophysical Research
- Numerical methods for differential equations
- Geophysics and Gravity Measurements
- Cryospheric studies and observations
- Climate change and permafrost
- Ecology and Vegetation Dynamics Studies
- Wind and Air Flow Studies
- Atmospheric and Environmental Gas Dynamics
- Archaeology and ancient environmental studies
- Atmospheric aerosols and clouds
- Ancient and Medieval Archaeology Studies
- Advanced Sensor and Energy Harvesting Materials
- Forest ecology and management
- Electromagnetic Simulation and Numerical Methods
- Matrix Theory and Algorithms
- Remote Sensing in Agriculture
Met Office
2012-2024
University of East Anglia
2007-2022
University of Portsmouth
2013-2016
University of Southampton
2016
Phillips Exeter Academy
2013
Climate model projections suggest widespread drying in the Mediterranean Basin and wetting Fennoscandia coming decades largely as a consequence of greenhouse gas forcing climate. To place these other "Old World" climate into historical perspective based on more complete estimates natural hydroclimatic variability, we have developed World Drought Atlas" (OWDA), set year-to-year maps tree-ring reconstructed summer wetness dryness over Europe during Common Era. The OWDA matches accounts severe...
We present the data release for Galaxy Zoo 2 (GZ2), a citizen science project with more than 16 million morphological classifications of 304 122 galaxies drawn from Sloan Digital Sky Survey (SDSS). Morphology is powerful probe quantifying galaxy's dynamical history; however, automatic morphology (either by computer analysis images or using other physical parameters as proxies) still have drawbacks when compared to visual inspection. The large number available in current surveys makes...
An annually resolved and absolutely dated ring-width chronology spanning 4,500 y has been constructed using subfossil, archaeological, living-tree juniper samples from the northeastern Tibetan Plateau. The represents changing mean annual precipitation is most reliable after 1500 B.C. Reconstructed for this period displays a trend toward more moist conditions: last 10-, 25-, 50-y periods all appear to be wettest in at least three half millennia. Notable historical dry occurred 4th century BCE...
Abstract. We describe Global Atmosphere 6.0 and Land (GA6.0/GL6.0): the latest science configurations of Met Office Unified Model JULES (Joint UK Environment Simulator) land surface model developed for use across all timescales. includes ENDGame (Even Newer Dynamics General atmospheric modelling environment) dynamical core, which significantly increases mid-latitude variability improving a known bias. Alongside developments model's physical parametrisations, also in tropics, leads to an...
Following previous work on an inherently mass‐conserving semi‐implicit (SI) semi‐Lagrangian (SL) discretization of the two‐dimensional (2D) shallow‐water equations and 2D vertical slice equations, that approach is here extended to 3D deep‐atmosphere, non‐hydrostatic global equations. As with reduced‐dimension versions this model, advantage it preserves same basic structure as a standard, non‐mass‐conserving, SISL version model. Additionally, model simply switchable hydrostatic and/or...
Abstract We combine satellite and ground observations during 1950–2011 to study the long‐term links between multiple climate (air temperature cryospheric dynamics) vegetation (greenness atmospheric CO 2 concentrations) indicators of growing season northern ecosystems (>45°N) their connection with carbon cycle. During last three decades, thermal potential has lengthened by about 10.5 days ( P < 0.01, 1982–2011), which is unprecedented in context past 60 years. The overall lengthening...
New and well‐dated evidence of sulphate deposits in Greenland Antarctic ice cores indicate a substantial extensive atmospheric acidic dust veil at A.D. 533–534 ± 2 years. This was likely produced by large explosive, near equatorial volcanic eruption, causing widespread dimming contributing to the abrupt cooling across much Northern Hemisphere known from historical records tree‐ring data have occurred 536. Tree‐ring suggest that this most severe protracted short‐term cold episode last two...
This paper describes variability in trends of annual tree growth at several locations the high latitudes Eurasia, providing a wide regional comparison over 2000-year period. The study focuses on nature local and widespread tree-growth responses to recent warming seen instrumental observations, available northern regions for periods ranging from decades century. Instrumental temperature data demonstrate differences seasonal scale Eurasian complexity spatial diversity tree-growing-season...
In this paper, we use the Galaxy Zoo 2 data set to study behavior of bars in disk galaxies as a function specific star formation rate (SSFR) and bulge prominence. Our sample consists 13,295 galaxies, with an overall (strong) bar fraction 23.6% ± 0.4%, which 1154 barred also have length (BL) measurements. These samples are largest ever used role galaxy evolution. We find that likelihood hosting is anticorrelated SSFR, regardless stellar mass or trends BL prominence bimodal SSFR. interpret...
We measure the redshift evolution of bar fraction in a sample 2380 visually selected disc galaxies found Cosmic Evolution Survey (COSMOS) Hubble Space Telescope (HST) images. The visual classifications used to identify both and indicate presence stellar bars were provided by citizen scientists via Galaxy Zoo: (GZH) project. find that overall decreases factor two, from 22+/-5% at z=0.4 (tlb = 4.2 Gyr) 11+/-2% z=1.0 7.8 Gyr), consistent with previous analysis. show this decrease, strong volume...
This is the first of a two-part description new software tool CRUST (Climatic Research Unit Standardisation Tree-ring data). program has been designed primarily to allow convenient, routine application "Signal-Free Regional Chronology Standardisation" (SF RCS) different types tree-ring data. The also enables use other popular standardisation methods. A series experiments described in which ability simple RCS and SF recover known tree-growth forcing signals tested. In comparatively rare...
We describe the analysis of existing and new maximum-latewood-density (MXD) tree-ring width (TRW) data from Torneträsk region northern Sweden construction 1500 year chronologies. Some previous work found that MXD TRW chronologies were inconsistent over most recent 200 years, even though they both reflect predominantly summer temperature influences on tree growth. show this was partly a result systematic bias in measurements inhomogeneous sample selection living trees (modern bias). use...
Does galaxy evolution proceed through the green valley via multiple pathways or as a single population? Motivated by recent results highlighting radically different evolutionary between early- and late-type galaxies, we present from simple Bayesian approach to this problem wherein model star formation history (SFH) of with two parameters, [t, τ] compare predicted observed optical near-ultraviolet colours. We use novel method investigate morphological differences most probable SFHs for both...
Tree rings are commonly used proxy data for past climate variability. Probably the simplest practical solution transforming raw tree-ring into estimates and retaining information on low-frequency tree-growth forcing is regional curve standardization (RCS). This paper reviews RCS concept development of this method over 25 years. Tree-ring based estimation variability illuminated with a growing diversification original concept. The RCS-type methods seen to remain as essential tools in...
Abstract The Arctic is warming faster than any other region on Earth. Putting this rapid into perspective challenging because instrumental records are often short or incomplete in polar regions and precisely-dated temperature proxies with high temporal resolution largely lacking. Here, we provide long-term by reconstructing past summer variability at Yamal Peninsula – a hotspot of recent over the 7638 years using annually resolved tree-ring records. We demonstrate that anthropogenic...
An ultra-long tree-ring width chronology (9111 years long, 7109 BC to AD 2002) has been established based on the analysis and dating of 1432 subfossil/dry dead wood samples cores from 335 living trees. The material was collected treeline or near-treeline sites ( c. 2000 2400 m a.s.l.) mainly in Eastern Alps. availability preserved through time at high altitudinal is influenced by Alpine forest history partly climatically controlled, as shown comparisons sample depth record Conifer Chronology...
The development of research into the history tree growth and inferred summer temperature changes in Yamalia spanning last 2000 years is reviewed. One focus evolving production tree-ring width (TRW) maximum-latewood density (MXD) larch (Larix sibirica) chronologies, incorporating different applications Regional Curve Standardisation (RCS). Another comparison independent data representing past adjacent areas: Yamal Polar Urals, examination evidence for common behaviour at timescales. sample we...
Gridded daily temperature from 1950 to 2011 and atmospheric CO 2 concentration data high‐latitude observing stations the CarbonTracker assimilation system are used examine recent spatiotemporal variability of thermal growing season its relationship with seasonal biospheric carbon uptake release in Northern Hemisphere. The has lengthened substantially since but most lengthening occurred during last three decades (2.9 days decade −1 , p < 0.01 for 1980–2011), stronger rates extension...
Recent warming has stimulated the productivity of boreal and Arctic vegetation by reducing temperature limitations. However, several studies have hypothesized that may also increased moisture limitations because intensified summer drought severity. Establishing connections between stress been difficult soil observations are scarce. Here we use recently developed gridded datasets variability to investigate links changes in available photosynthetic activity at northern latitudes (>45°N)...
The formation of bars in disc galaxies is a tracer the dynamical maturity population. Previous studies have found that incidence discs decreases from local Universe to z ∼ 1, and by > 1 simulations predict bar features dynamically mature should be extremely rare. Here, we report discovery strong barred structures massive at 1.5 deep rest-frame optical images Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey. From within sample 876 identified visual classification Galaxy Zoo,...