Helene Løvstrand Svarva
Biographic Data
| ID | 4456798 |
|---|---|
| NAME | Helene Løvstrand Svarva |
| GIVEN NAMES | Helene Løvstrand |
| FAMILY NAME | Svarva |
| SIGNATURE | SVARVA H L |
| AFFILIATIONS | Norwegian University of Science and Technology |
| ORCID | 0000-0001-8501-4767 |
| VERIFIED | Yes |
| TOTAL WORKS | 11 |
| TOTAL CITATIONS | 18 |
| AUTHOR COUNT | 11 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2015 |
| LATEST PUBLICATION YEAR | 2026 |
| H-INDEX | 2 |
Determining vertical growth patterns and tissue of maximum age using radiocarbon dating in the long-lived Namib Desert plant Welwitschia mirabilis
Welwitschia mirabilis , a unique gymnosperm native to Namibia and Angola, is a keystone plant species in the Namib Desert. It represents the only extremely long-lived non-clonal plant species occurring under hyperarid desert conditions, yet limited attempts have been made to accurately determine its age. Here, we present radiocarbon dates from a dead, sectioned Welwitschia of moderate size. We find the outer caudex tissue growth to progressively …
The Little Ice Age
First coined in the 1930s, with reference to glaciation in North America, the concept of the “Little Ice Age” has undergone continuous revisions. It has traveled academically from glaciology to climatology, archeology, history, and, most recently, climate communication. Over time, it has grown into one of the most discussed topics in the field of climate history and attracts both considerable scholarly interest and public attention. The term “Lit…
Modeling the contribution of carbon sources using cellulose 14C concentrations in subannual tree ring increments over the 1963 bomb spike
Measurements of the radiocarbon ( 14 C) content of subannual wood cellulose samples over the 1963 bomb spike have revealed an apparent delay between the increase in atmospheric radiocarbon content and that of wood cellulose. This delay is apparent in both coniferous and deciduous tree species and is of a magnitude of approximately 4 weeks. The delay in wood cellulose 14 C change as measured in a Sitka spruce from Washington state, USA, was previo…
Unravelling the History of a Venetian Antiphonary
We present the results of a multifaceted study of an antiphonary—liturgical song book—presumably made in Venice in 1607, now in the Ringve, National Music Museum of Norway in Trondheim 1 . The book is hand-sewn on raised cords, bound in full leather on cardboard covers, originally with metal clamps. The paper block consists of pages printed in black and red that include both song texts and music scores. The red ink is based on vermillion and red …
Squeaky Clean Cellulose
Obtaining accurate radiocarbon ( 14 C) results from wood samples requires the extraction of cellulose. In the past, this has been done using different combinations of methods including acidified bleaching, acid-base-acid, and strong bases. This often becomes a time-consuming task in most analyses, especially when single ring isotope chronologies are needed from wood samples. Using 14 C and Fourier-transform infrared spectroscopy (FTIR), we tested…
The Radiocarbon Sample Archive of Trondheim
Atmospheric CO 2 samples have been collected by the Trondheim Radiocarbon Laboratory since the 1960s. The remaining material from the measurements has been precipitated as CaCO 3 and stored in glass containers. We investigated some of the stored samples to assess whether the material could still be used for remeasurements of atmospheric radiocarbon ( 14 C) content, or if it has been contaminated during the years of storage. We attempted different…
Status report of the Trondheim Radiocarbon Laboratory
The Trondheim radiocarbon ( 14 C) laboratory has evolved from a traditional radiocarbon decay counting laboratory to an accelerator mass spectrometry (AMS) facility primarily measuring 14 C. This evolution required adjustments in sample preparation and data handling to match the capacity of the AMS system and reduction in sample sizes to about 1 mgC. We summarize here the steps involved in dating a sample at the National Laboratory for Age Determ…
The 1953–1965 rise in Atmospheric bomb 14 C in Central Norway
Sub-annual measurements, eight increments per year, of cellulose in a Scots pine tree growing in central Norway are presented as a proxy for tropospheric 14 CO 2 at biweekly to monthly resolution. The results are validated by comparison to direct atmospheric measurements in the years 1959–1965, and a new dataset is obtained for 1953–1958. In this period, our cellulose measurements deviate from the Bomb 13 NH1 calibration curve, which is derived f…
Radiocarbon Calibration around AD 1900 from Scots Pine ( Pinus Sylvestris ) tree rings from Northern Norway
To resolve an inconsistency around AD 1895 between radiocarbon ( 14 C) measurements on oak from the British Isles and Douglas fir and Sitka spruce from the Pacific Northwest, USA, we measured the 14 C content in single-year tree rings from a Scots pine tree ( Pinus sylvestris L.), which grew in a remote location in Saltdal, northern Norway. The dataset covers the period AD 1864–1937 and its results are in agreement with measurements from the US P…
Little Ice Age summer temperatures in western Norway from a 700-year tree-ring chronology
A ring-width Pinus sylvestris chronology from Sogndal in western Norway was created, covering the period AD 1240–2008 and allowing for reconstruction of monthly mean July temperatures. This reconstruction is the first of its kind from western Norway and it aims to densify the existing network of temperature-sensitive tree-ring proxy series to better understand past temperature variability in the ‘Little Ice Age’ and diminish the spatial uncertain…
Old World megadroughts and pluvials during the Common Era
An atlas of megadroughts in Europe and in the Mediterranean Basin during the Common Era provides insights into climate variability.
Status report of the Trondheim Radiocarbon Laboratory
The Trondheim radiocarbon ( 14 C) laboratory has evolved from a traditional radiocarbon decay counting laboratory to an accelerator mass spectrometry (AMS) facility primarily measuring 14 C. This evolution required adjustments in sample preparation and data handling to match the capacity of the AMS system and reduction in sample sizes to about 1 mgC. We summarize here the steps involved in dating a sample at the National Laboratory for Age Determ…
The 1953–1965 rise in Atmospheric bomb 14 C in Central Norway
Sub-annual measurements, eight increments per year, of cellulose in a Scots pine tree growing in central Norway are presented as a proxy for tropospheric 14 CO 2 at biweekly to monthly resolution. The results are validated by comparison to direct atmospheric measurements in the years 1959–1965, and a new dataset is obtained for 1953–1958. In this period, our cellulose measurements deviate from the Bomb 13 NH1 calibration curve, which is derived f…
Squeaky Clean Cellulose
Obtaining accurate radiocarbon ( 14 C) results from wood samples requires the extraction of cellulose. In the past, this has been done using different combinations of methods including acidified bleaching, acid-base-acid, and strong bases. This often becomes a time-consuming task in most analyses, especially when single ring isotope chronologies are needed from wood samples. Using 14 C and Fourier-transform infrared spectroscopy (FTIR), we tested…
The Radiocarbon Sample Archive of Trondheim
Atmospheric CO 2 samples have been collected by the Trondheim Radiocarbon Laboratory since the 1960s. The remaining material from the measurements has been precipitated as CaCO 3 and stored in glass containers. We investigated some of the stored samples to assess whether the material could still be used for remeasurements of atmospheric radiocarbon ( 14 C) content, or if it has been contaminated during the years of storage. We attempted different…
Radiocarbon Calibration around AD 1900 from Scots Pine ( Pinus Sylvestris ) tree rings from Northern Norway
To resolve an inconsistency around AD 1895 between radiocarbon ( 14 C) measurements on oak from the British Isles and Douglas fir and Sitka spruce from the Pacific Northwest, USA, we measured the 14 C content in single-year tree rings from a Scots pine tree ( Pinus sylvestris L.), which grew in a remote location in Saltdal, northern Norway. The dataset covers the period AD 1864–1937 and its results are in agreement with measurements from the US P…
Little Ice Age summer temperatures in western Norway from a 700-year tree-ring chronology
A ring-width Pinus sylvestris chronology from Sogndal in western Norway was created, covering the period AD 1240–2008 and allowing for reconstruction of monthly mean July temperatures. This reconstruction is the first of its kind from western Norway and it aims to densify the existing network of temperature-sensitive tree-ring proxy series to better understand past temperature variability in the ‘Little Ice Age’ and diminish the spatial uncertain…
Old World megadroughts and pluvials during the Common Era
An atlas of megadroughts in Europe and in the Mediterranean Basin during the Common Era provides insights into climate variability.
Little Ice Age summer temperatures in western Norway from a 700-year tree-ring chronology
A ring-width Pinus sylvestris chronology from Sogndal in western Norway was created, covering the period AD 1240–2008 and allowing for reconstruction of monthly mean July temperatures. This reconstruction is the first of its kind from western Norway and it aims to densify the existing network of temperature-sensitive tree-ring proxy series to better understand past temperature variability in the ‘Little Ice Age’ and diminish the spatial uncertain…
Status report of the Trondheim Radiocarbon Laboratory
The Trondheim radiocarbon ( 14 C) laboratory has evolved from a traditional radiocarbon decay counting laboratory to an accelerator mass spectrometry (AMS) facility primarily measuring 14 C. This evolution required adjustments in sample preparation and data handling to match the capacity of the AMS system and reduction in sample sizes to about 1 mgC. We summarize here the steps involved in dating a sample at the National Laboratory for Age Determ…
The 1953–1965 rise in Atmospheric bomb 14 C in Central Norway
Sub-annual measurements, eight increments per year, of cellulose in a Scots pine tree growing in central Norway are presented as a proxy for tropospheric 14 CO 2 at biweekly to monthly resolution. The results are validated by comparison to direct atmospheric measurements in the years 1959–1965, and a new dataset is obtained for 1953–1958. In this period, our cellulose measurements deviate from the Bomb 13 NH1 calibration curve, which is derived f…
Radiocarbon Calibration around AD 1900 from Scots Pine ( Pinus Sylvestris ) tree rings from Northern Norway
To resolve an inconsistency around AD 1895 between radiocarbon ( 14 C) measurements on oak from the British Isles and Douglas fir and Sitka spruce from the Pacific Northwest, USA, we measured the 14 C content in single-year tree rings from a Scots pine tree ( Pinus sylvestris L.), which grew in a remote location in Saltdal, northern Norway. The dataset covers the period AD 1864–1937 and its results are in agreement with measurements from the US P…
The Radiocarbon Sample Archive of Trondheim
Atmospheric CO 2 samples have been collected by the Trondheim Radiocarbon Laboratory since the 1960s. The remaining material from the measurements has been precipitated as CaCO 3 and stored in glass containers. We investigated some of the stored samples to assess whether the material could still be used for remeasurements of atmospheric radiocarbon ( 14 C) content, or if it has been contaminated during the years of storage. We attempted different…
Unravelling the History of a Venetian Antiphonary
We present the results of a multifaceted study of an antiphonary—liturgical song book—presumably made in Venice in 1607, now in the Ringve, National Music Museum of Norway in Trondheim 1 . The book is hand-sewn on raised cords, bound in full leather on cardboard covers, originally with metal clamps. The paper block consists of pages printed in black and red that include both song texts and music scores. The red ink is based on vermillion and red …
Squeaky Clean Cellulose
Obtaining accurate radiocarbon ( 14 C) results from wood samples requires the extraction of cellulose. In the past, this has been done using different combinations of methods including acidified bleaching, acid-base-acid, and strong bases. This often becomes a time-consuming task in most analyses, especially when single ring isotope chronologies are needed from wood samples. Using 14 C and Fourier-transform infrared spectroscopy (FTIR), we tested…
The Little Ice Age
First coined in the 1930s, with reference to glaciation in North America, the concept of the “Little Ice Age” has undergone continuous revisions. It has traveled academically from glaciology to climatology, archeology, history, and, most recently, climate communication. Over time, it has grown into one of the most discussed topics in the field of climate history and attracts both considerable scholarly interest and public attention. The term “Lit…
Modeling the contribution of carbon sources using cellulose 14C concentrations in subannual tree ring increments over the 1963 bomb spike
Measurements of the radiocarbon ( 14 C) content of subannual wood cellulose samples over the 1963 bomb spike have revealed an apparent delay between the increase in atmospheric radiocarbon content and that of wood cellulose. This delay is apparent in both coniferous and deciduous tree species and is of a magnitude of approximately 4 weeks. The delay in wood cellulose 14 C change as measured in a Sitka spruce from Washington state, USA, was previo…
Determining vertical growth patterns and tissue of maximum age using radiocarbon dating in the long-lived Namib Desert plant Welwitschia mirabilis
Welwitschia mirabilis , a unique gymnosperm native to Namibia and Angola, is a keystone plant species in the Namib Desert. It represents the only extremely long-lived non-clonal plant species occurring under hyperarid desert conditions, yet limited attempts have been made to accurately determine its age. Here, we present radiocarbon dates from a dead, sectioned Welwitschia of moderate size. We find the outer caudex tissue growth to progressively …
Radiocarbon dating (8 works) · Geography (6 works) · Geology (6 works) · Tree-ring climate responses (6 works) · Archaeology (4 works) · Chemistry (4 works) · Geology and Paleoclimatology Research (4 works) · Paleontology (4 works) · Archaeology and ancient environmental studies (3 works) · Dendrochronology (3 works)