Periodic Reporting for period 1 - ITHACA (medITerranean HydroclimAte variability over the Common erA)
Berichtszeitraum: 2022-09-01 bis 2024-08-31
The ITHACA project investigates hydroclimate extremes in the Mediterranean over the last two thousand years. It develops a cutting-edge paleo data assimilation product, combining proxy-data with climate model simulations, to provide historical context for future climate projections. This research informs policy-making, assesses climate change risks, and attributes anthropogenic activities to hydroclimatic changes. Ultimately, this knowledge can assist in developing effective strategies for adapting to and mitigating the impacts of climate change in the Mediterranean region and beyond.
The ITHACA project started by compiling a comprehensive dataset of paleoclimate data, which includes various sources such as historical archives, tree ring records, lake sediments, ice cores, and old instrumental records. This dataset is extensive and covers a significant portion of Europe and the Mediterranean regions, providing a robust foundation for climate reconstructions. However, it is noted that the African Mediterranean countries have fewer records available, resulting in higher uncertainties in the final product for those regions.
In addition to the ITHACA project, I also participated as a co-author in a publication titled "DOCU-Clim: A global documentary climate dataset for climate reconstructions," which has been published in the journal Scientific Reports. This publication introduces a global dataset of documentary data spanning the last 500 years, providing valuable information for climate reconstructions. The dataset is now accessible online in a standardized format, enhancing its usability and facilitating further research in the field.In parallel to the compilation of the paleoclimate dataset, I have been collaborating with Dr. Nathan Steiger on the data assimilation methodology, with a specific focus on the bias correction step. Bias correction is an important aspect of data assimilation, as it aims to correct any systematic errors or biases present in the data. This step ensures that the assimilated data align more accurately with the climate model simulation and improves the reliability of the final product.
The Journal of Climate is currently reviewing a preliminary version of our data assimilation product. This version incorporates diverse sources of information, including old instrumental data, tree rings, and ice cores. The primary focus of this product is the reconstruction of winter temperatures over Eurasia throughout the last millennium. In our manuscript titled "Last Millennium evidence of winter cooling over Eurasia following large, low-latitude volcanic eruptions", we present a challenge to the previously accepted paradigm of winter warming over Eurasia following significant tropical volcanic eruptions. Our novel data assimilation product does not support the existence of winter warming following these eruptions. Consequently, the mechanisms that were previously proposed to explain this warming are no longer considered valid. Furthermore, our analysis of the 20 largest eruptions within the Last Millennium reveals compelling evidence of winter surface cooling during the first winter following these eruptions. This finding contradicts the notion of warming and highlights the importance of considering the cooling effects of volcanic eruptions on winter temperatures over Eurasia.
By the end of the summer, we are aiming to have the second version of our product for the ITHACA project, which will include temperature, hydroclimate, and associated variables. A paper describing the new methodology and the datasets is programmed to be submitted in Fall.
Finally, I worked as a co-leading author the paper titled "Unprecedented warmth: A look at Spain’s exceptional summer of 2022", which is currently in review in the journal Atmospheric Research. In this paper, we characterized the extreme climate (temperature at 2 m, sea surface temperature, Urban Heat Island, hydroclimate, and climate dynamics) of the 2022 summer, which was unprecedented within the instrumental period and the warmest in the last 700 years in Spain.
In addition to the ITHACA project, I also participated as a co-author in a publication titled "DOCU-Clim: A global documentary climate dataset for climate reconstructions," which has been published in the journal Scientific Reports. This publication introduces a global dataset of documentary data spanning the last 500 years, providing valuable information for climate reconstructions. The dataset is now accessible online in a standardized format, enhancing its usability and facilitating further research in the field.In parallel to the compilation of the paleoclimate dataset, I have been collaborating with Dr. Nathan Steiger on the data assimilation methodology, with a specific focus on the bias correction step. Bias correction is an important aspect of data assimilation, as it aims to correct any systematic errors or biases present in the data. This step ensures that the assimilated data align more accurately with the climate model simulation and improves the reliability of the final product.
The Journal of Climate is currently reviewing a preliminary version of our data assimilation product. This version incorporates diverse sources of information, including old instrumental data, tree rings, and ice cores. The primary focus of this product is the reconstruction of winter temperatures over Eurasia throughout the last millennium. In our manuscript titled "Last Millennium evidence of winter cooling over Eurasia following large, low-latitude volcanic eruptions", we present a challenge to the previously accepted paradigm of winter warming over Eurasia following significant tropical volcanic eruptions. Our novel data assimilation product does not support the existence of winter warming following these eruptions. Consequently, the mechanisms that were previously proposed to explain this warming are no longer considered valid. Furthermore, our analysis of the 20 largest eruptions within the Last Millennium reveals compelling evidence of winter surface cooling during the first winter following these eruptions. This finding contradicts the notion of warming and highlights the importance of considering the cooling effects of volcanic eruptions on winter temperatures over Eurasia.
By the end of the summer, we are aiming to have the second version of our product for the ITHACA project, which will include temperature, hydroclimate, and associated variables. A paper describing the new methodology and the datasets is programmed to be submitted in Fall.
Finally, I worked as a co-leading author the paper titled "Unprecedented warmth: A look at Spain’s exceptional summer of 2022", which is currently in review in the journal Atmospheric Research. In this paper, we characterized the extreme climate (temperature at 2 m, sea surface temperature, Urban Heat Island, hydroclimate, and climate dynamics) of the 2022 summer, which was unprecedented within the instrumental period and the warmest in the last 700 years in Spain.
The ITHACA project holds significant potential for impacts beyond the state of the art in several areas. Some of the expected and potential impacts include:
Advancing paleoclimate understanding: The project aims to advance the understanding of paleoclimate over the Mediterranean basin during the Common Era. By combining high-resolution paleo proxy-data time series with the constraints of an atmosphere-ocean climate model simulation, the project will provide valuable insights into the characteristics and causes of hydroclimate extremes. This enhanced understanding will contribute to improving our knowledge of past climate variability and help place future climate projections within a broader historical context.
Informing policy and decision-making: The project seeks to inform policy and decision-making processes related to climate change. By providing a robust paleoclimate dataset and a state-of-the-art paleo data assimilation product, policymakers and stakeholders will have access to valuable information on hydroclimatic variability in the Mediterranean region. This knowledge can guide the development of effective adaptation and mitigation strategies and support evidence-based decision-making to address the risks of climate change.
Attribution of anthropogenic activities: The project aims to address the attribution of anthropogenic activities to current changes in hydroclimatic extremes. By combining the paleoclimate dataset with the analysis of recent changes in hydroclimatic patterns, the project will contribute to understanding the role of human activities in shaping the observed climate variations. This attribution is crucial for identifying the drivers of climate change and designing appropriate mitigation measures.
Risk assessment and management: The project's outcomes will provide guidance for process-based risk assessment tools. By understanding the characteristics, causes, and impacts of hydroclimate extremes, stakeholders can better assess and manage the risks associated with climate change in the Mediterranean region. This information can support the development of effective risk reduction strategies, such as improved water management practices, ecosystem conservation measures, and infrastructure planning.
Scientific advancements and interdisciplinary collaborations: The ITHACA project involves advancements in data assimilation methodologies, particularly in the bias correction step, as mentioned earlier. These developments contribute to the broader field of climate research and modeling. The project also encourages interdisciplinary collaborations between paleoclimatologists, climate modelers, policy experts, and stakeholders, fostering a multidisciplinary approach to addressing climate change challenges.
Overall, the ITHACA project's expected impacts beyond the state of the art encompass advancing paleoclimate understanding, informing policy and decision-making, attributing anthropogenic activities, facilitating risk assessment and management, and driving scientific advancements through interdisciplinary collaborations. These outcomes have the potential to enhance our ability to address the complex challenges posed by climate change in the Mediterranean region and beyond.
Advancing paleoclimate understanding: The project aims to advance the understanding of paleoclimate over the Mediterranean basin during the Common Era. By combining high-resolution paleo proxy-data time series with the constraints of an atmosphere-ocean climate model simulation, the project will provide valuable insights into the characteristics and causes of hydroclimate extremes. This enhanced understanding will contribute to improving our knowledge of past climate variability and help place future climate projections within a broader historical context.
Informing policy and decision-making: The project seeks to inform policy and decision-making processes related to climate change. By providing a robust paleoclimate dataset and a state-of-the-art paleo data assimilation product, policymakers and stakeholders will have access to valuable information on hydroclimatic variability in the Mediterranean region. This knowledge can guide the development of effective adaptation and mitigation strategies and support evidence-based decision-making to address the risks of climate change.
Attribution of anthropogenic activities: The project aims to address the attribution of anthropogenic activities to current changes in hydroclimatic extremes. By combining the paleoclimate dataset with the analysis of recent changes in hydroclimatic patterns, the project will contribute to understanding the role of human activities in shaping the observed climate variations. This attribution is crucial for identifying the drivers of climate change and designing appropriate mitigation measures.
Risk assessment and management: The project's outcomes will provide guidance for process-based risk assessment tools. By understanding the characteristics, causes, and impacts of hydroclimate extremes, stakeholders can better assess and manage the risks associated with climate change in the Mediterranean region. This information can support the development of effective risk reduction strategies, such as improved water management practices, ecosystem conservation measures, and infrastructure planning.
Scientific advancements and interdisciplinary collaborations: The ITHACA project involves advancements in data assimilation methodologies, particularly in the bias correction step, as mentioned earlier. These developments contribute to the broader field of climate research and modeling. The project also encourages interdisciplinary collaborations between paleoclimatologists, climate modelers, policy experts, and stakeholders, fostering a multidisciplinary approach to addressing climate change challenges.
Overall, the ITHACA project's expected impacts beyond the state of the art encompass advancing paleoclimate understanding, informing policy and decision-making, attributing anthropogenic activities, facilitating risk assessment and management, and driving scientific advancements through interdisciplinary collaborations. These outcomes have the potential to enhance our ability to address the complex challenges posed by climate change in the Mediterranean region and beyond.