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jonnyday.bsky.social

@jonnyday.bsky.social
50 followers 172 following 13 posts

Scientist at ECMWF

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jonnyday.bsky.social @jonnyday.bsky.social · 09/07/2026
Great illustration of the profound impact of El-Nino on the hydro meteorology of the USA, but also the variety within that sample
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jonnyday.bsky.social @jonnyday.bsky.social · 01/06/2026
📢 Places still available on the ECMWF training course: Predictability & Ensemble Forecast Systems 
📍 Reading | 🗓️ 19–23 Oct 2026 More info & registration 👉 events.ecmwf.int/event/545/ #ECMWF #Predictability #Ensembles #NWP #Weather
events.ecmwf.int
Training course: Predictability and ensemble forecast systems
This five-day course will consider the challenge of making predictions from days to seasons ahead. The predictability of the atmosphere in the medium and extended range will be considered, including d...
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Reposted by @jonnyday.bsky.social
Constantin Ardilouze @crdlz.bsky.social · 29/09/2025
Proud to announce the publication of our latest paper led by Gabriel Narvaez-Campo in the @egu.eu journal #HESS. A novel approach on river streamflow seasonal prediction at the global scale. @meteofrance.com @cnrs-insu.bsky.social @hepexorg.bsky.social hess.copernicus.org/articles/29/...
hess.copernicus.org
Skilful seasonal streamflow forecasting using a fully coupled global climate model
Abstract. The seasonal streamflow forecast (SSF) is a crucial decision-making, planning and management tool for disaster prevention, navigation, agriculture and hydropower generation. This study demon...
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jonnyday.bsky.social @jonnyday.bsky.social · 24/09/2025
Scatterometer is used in ERA5. See table 4: rmets.onlinelibrary.wiley.com/doi/abs/10.1... Contrast with ERA5-land, which assimilated no data.
rmets.onlinelibrary.wiley.com
The ERA5 global reanalysis
This paper presents a comprehensive overview of the ERA5 global reanalysis from 1979 onwards, which is produced at ECMWF as part of the Copernicus Climate Change Service. It provides a detailed...
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jonnyday.bsky.social @jonnyday.bsky.social · 14/08/2025
Cherry picking this to debunk the whole climate modelling exercise is clearly a bad faith argument, but these sort of trend errors would, at face value, be a real issue for e.g. an agro sector end user and should be a focus for model development.
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jonnyday.bsky.social @jonnyday.bsky.social · 13/08/2025
The issue with JJA T2m trends over the US is consistent with this paper www.nature.com/articles/s41... linking the strength of a warm/dry bias over the central US to magnitude of regional temperature change. It's a common issue and relates to convective precip and land-atmosphere coupling.
nature.com
Causes of model dry and warm bias over central U.S. and impact on climate projections - Nature Communications
Climate models repeatedly show a warm and dry bias over the central United States, but the origin of this bias remains unclear. Here the authors associate this bias to precipitation deficits in models...
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jonnyday.bsky.social @jonnyday.bsky.social · 27/06/2025
Thanks for all the helpful discussions!
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jonnyday.bsky.social @jonnyday.bsky.social · 27/06/2025
cc. @crdlz.bsky.social @hepexorg.bsky.social @gewex.bsky.social @copernicusecmwf.bsky.social @ecmwf.int
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jonnyday.bsky.social @jonnyday.bsky.social · 27/06/2025
3. Soil moisture “memory” offers a pathway for improving summer forecasts, but only if models better capture land–atmosphere feedbacks.
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jonnyday.bsky.social @jonnyday.bsky.social · 27/06/2025
2. However, some areas—like Eastern Europe and Northern India—exhibit 𝗲𝘅𝗮𝗴𝗴𝗲𝗿𝗮𝘁𝗲𝗱 𝗰𝗼𝘂𝗽𝗹𝗶𝗻𝗴, introducing forecast biases.
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jonnyday.bsky.social @jonnyday.bsky.social · 27/06/2025
The key findings are: 1. Regions such as western North America, southern Europe, and Central Asia show further potential for seasonal temperature and precipitation prediction skill based on soil moisture anomalies.
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jonnyday.bsky.social @jonnyday.bsky.social · 27/06/2025
Excited to share our new paper in @springernature.com Climate Dynamics exploring soil moisture–atmosphere coupling hotspots across the Northern Hemisphere in @copernicusecmwf.bsky.social #C3S #Seasonal forecasts. link.springer.com/article/10.1... #ClimateScience #SoilMoisture #ClimateResearch
link.springer.com
Soil-moisture-atmosphere coupling hotspots and their representation in seasonal forecasts of boreal summer - Climate Dynamics
This study examines soil-moisture-atmosphere coupling “hotspots” across the Northern Hemisphere during the summer months and evaluates their representation in seasonal forecasting systems. Using hindc...
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Reposted by @jonnyday.bsky.social
Hugh Pumphrey @hughpumphrey.bsky.social · 26/06/2025
Today's @xkcd.com is definitely one for my atmospheric and climate sciences colleagues: xkcd.com/3107 (e.g. @gabihegerl.bsky.social @andrewdessler.com @simonleewx.com . . . )
xkcd.com
Weather Balloons
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jonnyday.bsky.social @jonnyday.bsky.social · 04/02/2025
Reminds me of this ill fated prediction of a sea ice free Arctic from Wadhams: www.theguardian.com/environment/.... following a similar methodology of fitting an exponential.
theguardian.com
Arctic expert predicts final collapse of sea ice within four years
As sea ice shrinks to record lows, Prof Peter Wadhams warns a 'global disaster' is now unfolding in northern latitudes
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jonnyday.bsky.social @jonnyday.bsky.social · 14/01/2025
🌍 New preprint: "Soil-moisture-atmosphere coupling hotspots in seasonal forecasts of boreal summer" explores how soil moisture affects seasonal predictions & highlights areas for improvement. Read here: doi.org/10.21203/rs.... #ClimateScience #SeasonalForecasting #LandAtmosphereInteractions
lnkd.in
LinkedIn
This link will take you to a page that’s not on LinkedIn
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Reposted by @jonnyday.bsky.social
Copernicus ECMWF @copernicusecmwf.bsky.social · 14/11/2024
The new #ECMWF IFS Cycle 49r1 brings some minor updates to #CopernicusAtmosphere, such as improved global emissions datasets and aerosol modelling. Read more about the changes and the impacts for CAMS at confluence.ecmwf.int/display/COPS...
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