Old weather “time machine” opens a treasure trove for researchers
One key to the past is crowd-sourcing data recovery
It’s been the stuff of science fiction for generations: a time machine that would
allow researchers to reach back into yesteryear and ask new questions about long-ago
events.
This month, a NOAA-funded research team published an update to a weather “time
machine” they’ve been developing since 2011. This third version of the 20th Century
Reanalysis Project, or 20CRv3 for short, is a dauntingly complex, high-resolution,
four-dimensional reconstruction of the global climate that estimates what the weather
was for every day back to 1836.
The newest update provides continuous estimates of the most likely state of the
global atmosphere’s weather on 75-kilometer grids eight times a day for the past 180
years. It’s the scientific fruit of an international effort led by researchers with
NOAA's Physical Sciences Laboratory (PSL) and CIRES
and supported by the Department of Energy.
The research opportunities that this work makes available are almost boundless,
said Gil Compo, a CIRES scientist working at PSL who leads the reanalysis project.
“We’re throwing open the door to lost history, and inviting scientists to pour
through,” Compo said.
Old weather records fed to modern weather model
Using NOAA’s Global Forecast System, researchers reconstructed the global
atmosphere from surface pressure readings, sea temperature and sea ice observations
from archival records, some transcribed by citizen volunteers.
From this data, the model estimates temperature, pressure, winds, moisture, solar radiation and clouds.
Scientists have used previous 20th Century Reanalysis datasets as a foundation
for a wide range of studies, from understanding large-scale climate trends to
diagnosing the impacts of individual historical extreme weather events. The dataset
allows researchers to explore how climate change is influencing temperature,
precipitation, and atmospheric circulation, and compare today’s storms, heat waves,
droughts and floods to historic events.
“This tool lets us quantitatively compare today’s storms, floods, blizzards, heat
waves and droughts to those of the past and figure out whether or not climate change
is having an effect,” Compo said. “This should be useful for climate attribution
research.”
Colorado State University hurricane researcher Phil Klotzbach said he can’t wait
to begin working with 20CRv3. “I’m a huge fan of reanalysis products,” said
Klotzbach. “I’ll probably be diving in by next week and I know my colleagues are
looking forward to working with it.”
Enriching our understanding of long-ago events
Scientists have also used the previous versions of the “old weather” data to
discover unknown hurricanes, study the climate impact of old volcanic eruptions,
investigate the timing of bird migrations, and even explore the economic impact of
diseases spread by the tsetse fly in sub-Saharan Africa.
Others have used the data to enrich the scientific understanding of specific
weather lodged in cultural memory, like the sinking of the Titanic or the
extraordinary winter of 1880-1881, which was chronicled by Laura Ingalls Wilder in
her book “The Long Winter.”
“I’ve found reanalysis composites incredibly useful and accessible,” said Barbara
Mayes Bousted, a meteorologist instructor with NOAA’s National Weather Service, who
has studied the winter of 1880-1881. “We introduce them in our course on operational
climate services and to weather forecast offices who want to investigate climate
events like the El Niño-Southern Oscillation.”
A big appetite for big data
20CRv3 uses millions more observations than previous versions of the reanalysis,
especially for earlier periods. The new reanalysis includes up to 25 percent more
available observations for years prior to 1930. Running the model and crunching all
this data required astronomical computing resources. To accomplish this third
upgrade, the Department of Energy donated 600 million cpu hours to crunch 21 million
gigabytes of data at the National Energy Research Scientific Computing Center.
The result? This new update provides a much better indication of where the
weather estimates are more reliable, and where more observations are needed.
“The atmospheric estimates from 20CRv3, as well as their uncertainties, are much
more reliable than those from the previous reanalysis, particularly in the 19th
century,” said Laura Slivinski, a CIRES meteorologist at PSL, and the lead author of a recent
paper in the Quarterly Journal of the Royal Meteorological Society that lays out
improvements in their reanalysis techniques. “We’re more certain about how much we
know, and where we need to know more.”
Citizen scientists help chart a “virtuous circle” of discovery
Some of the key players in the reanalysis story are groups like Atmospheric
Circulation Reconstructions over the Earth, which marshalls professional scientists
and ordinary citizens alike to pore over historical documents like ship logs and
extract meteorological observations that are used to refine old weather
reconstructions. Targeted data rescue can be extraordinarily valuable - for example,
logs of 19th Century wooden sailing vessels
attempting to penetrate the Arctic and Antarctic.
“These data have been invaluable to us because they come from the otherwise
data-sparse polar regions,” Slivinski said.
“20CRv3 also provides a literal map to further advances in precision by
identifying regions and time periods where additional weather observations will
improve model estimates,” she added.
Earlier time periods, especially in the Southern hemisphere, still have high
uncertainty. Luckily, data rescue can help fix that. “This dataset can keep getting
better as we unlock more observations from historical archives,” Compo said. “It’s
really a virtuous circle.”
The 20th Century Reanalysis Project version 3 dataset received support from the
U.S. Department of Energy, Office of Science Biological and Environmental Research
and NOAA's Climate Program Office.
For more information, contact: Theo Stein, NOAA Communications at theo.stein@noaa.gov.
To learn more about participating in data recovery, visit https://www.oldweather.org.
Posted: October 9, 2019
It’s been the stuff of science fiction for generations: a time machine that would allow researchers to reach back into yesteryear and ask new questions about long-ago events.
This month, a NOAA-funded research team published an update to a weather “time machine” they’ve been developing since 2011. This third version of the 20th Century Reanalysis Project, or 20CRv3 for short, is a dauntingly complex, high-resolution, four-dimensional reconstruction of the global climate that estimates what the weather was for every day back to 1836.
The newest update provides continuous estimates of the most likely state of the global atmosphere’s weather on 75-kilometer grids eight times a day for the past 180 years. It’s the scientific fruit of an international effort led by researchers with NOAA's Physical Sciences Laboratory (PSL) and CIRES and supported by the Department of Energy.
The research opportunities that this work makes available are almost boundless, said Gil Compo, a CIRES scientist working at PSL who leads the reanalysis project. “We’re throwing open the door to lost history, and inviting scientists to pour through,” Compo said.
Old weather records fed to modern weather model
Using NOAA’s Global Forecast System, researchers reconstructed the global atmosphere from surface pressure readings, sea temperature and sea ice observations from archival records, some transcribed by citizen volunteers. From this data, the model estimates temperature, pressure, winds, moisture, solar radiation and clouds.
Scientists have used previous 20th Century Reanalysis datasets as a foundation for a wide range of studies, from understanding large-scale climate trends to diagnosing the impacts of individual historical extreme weather events. The dataset allows researchers to explore how climate change is influencing temperature, precipitation, and atmospheric circulation, and compare today’s storms, heat waves, droughts and floods to historic events.
“This tool lets us quantitatively compare today’s storms, floods, blizzards, heat waves and droughts to those of the past and figure out whether or not climate change is having an effect,” Compo said. “This should be useful for climate attribution research.”
Colorado State University hurricane researcher Phil Klotzbach said he can’t wait to begin working with 20CRv3. “I’m a huge fan of reanalysis products,” said Klotzbach. “I’ll probably be diving in by next week and I know my colleagues are looking forward to working with it.”
Enriching our understanding of long-ago events
Scientists have also used the previous versions of the “old weather” data to discover unknown hurricanes, study the climate impact of old volcanic eruptions, investigate the timing of bird migrations, and even explore the economic impact of diseases spread by the tsetse fly in sub-Saharan Africa.
Others have used the data to enrich the scientific understanding of specific weather lodged in cultural memory, like the sinking of the Titanic or the extraordinary winter of 1880-1881, which was chronicled by Laura Ingalls Wilder in her book “The Long Winter.”
“I’ve found reanalysis composites incredibly useful and accessible,” said Barbara Mayes Bousted, a meteorologist instructor with NOAA’s National Weather Service, who has studied the winter of 1880-1881. “We introduce them in our course on operational climate services and to weather forecast offices who want to investigate climate events like the El Niño-Southern Oscillation.”
A big appetite for big data
20CRv3 uses millions more observations than previous versions of the reanalysis, especially for earlier periods. The new reanalysis includes up to 25 percent more available observations for years prior to 1930. Running the model and crunching all this data required astronomical computing resources. To accomplish this third upgrade, the Department of Energy donated 600 million cpu hours to crunch 21 million gigabytes of data at the National Energy Research Scientific Computing Center.
The result? This new update provides a much better indication of where the weather estimates are more reliable, and where more observations are needed.
“The atmospheric estimates from 20CRv3, as well as their uncertainties, are much more reliable than those from the previous reanalysis, particularly in the 19th century,” said Laura Slivinski, a CIRES meteorologist at PSL, and the lead author of a recent paper in the Quarterly Journal of the Royal Meteorological Society that lays out improvements in their reanalysis techniques. “We’re more certain about how much we know, and where we need to know more.”
Citizen scientists help chart a “virtuous circle” of discovery
Some of the key players in the reanalysis story are groups like Atmospheric Circulation Reconstructions over the Earth, which marshalls professional scientists and ordinary citizens alike to pore over historical documents like ship logs and extract meteorological observations that are used to refine old weather reconstructions. Targeted data rescue can be extraordinarily valuable - for example, logs of 19th Century wooden sailing vessels attempting to penetrate the Arctic and Antarctic.
“These data have been invaluable to us because they come from the otherwise data-sparse polar regions,” Slivinski said.
“20CRv3 also provides a literal map to further advances in precision by identifying regions and time periods where additional weather observations will improve model estimates,” she added.
Earlier time periods, especially in the Southern hemisphere, still have high uncertainty. Luckily, data rescue can help fix that. “This dataset can keep getting better as we unlock more observations from historical archives,” Compo said. “It’s really a virtuous circle.”
The 20th Century Reanalysis Project version 3 dataset received support from the U.S. Department of Energy, Office of Science Biological and Environmental Research and NOAA's Climate Program Office.
For more information, contact: Theo Stein, NOAA Communications at theo.stein@noaa.gov.
To learn more about participating in data recovery, visit https://www.oldweather.org.
Posted: October 9, 2019