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Lake Kinneret in a Changing Environment

Date:
12
Sunday
May
2024
Lecture / Seminar
Time: 11:00
Location: Sussman Family Building for Environmental Sciences
Lecturer: Yael Amitai
Organizer: Department of Earth and Planetary Sciences
Contact: dalia.madhala@weizmann.ac.il
Abstract: Located in a highly sensitive subtropical climate area and a densely populated a ... Read more Located in a highly sensitive subtropical climate area and a densely populated area, Lake Kinneret is poised to undergo both natural and human-induced transformations in the coming decades. The lake is thermally stratified throughout most of the year and mixes thoroughly each winter when the epilimnion (upper layer) water temperature reaches equilibrium with the hypolimnion (bottom layer) water temperature by surface cooling and turbulence. Both the stratified and the fully mixed periods has a significant role in the Kinneret’s ecological system. Observation shows that air above the Lake is warming in a rate of 0.4oC/decade, while the epilimnion and hypolimnion are warming in a rate of 0.3oC/decade and 0.1oC/decade, respectively, for the last 50 years. Therefore, stratification strength and duration is anticipated to change and impact the lake’s ecosystem. Additionally, the sequence of drought periods and the expected future rise in water demands from Lake Kinneret formed the basis for the government's decision to channel desalinated water, via the natural course of the Tzalmon Stream, to the lake to ensure its operational functionality at high levels. Using a 3D hydrodynamic model forced by short and long-term forecasts the above scenarios are examined and analyzed. A simulation forced by regional atmospheric RCP4.5 climate change scenario spanning from 2010-2070 show continuous warming followed by abrupt cooling of the lake water around the year 2065. This result, presumably due to enhanced latent heat loss, suggest a restrain the dramatic anticipated change in the lake stratification.
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Data synthesis to assess the effects of climate change on agricultural production and food security

Date:
30
Sunday
June
2024
Lecture / Seminar
Time: 11:00
Location: Sussman Family Building for Environmental Sciences
Lecturer: David Makowski
Organizer: Department of Earth and Planetary Sciences
Contact: dalia.madhala@weizmann.ac.il
Abstract: Climate change is having an impact on agricultural production and food security ... Read more Climate change is having an impact on agricultural production and food security. Rising temperatures, changes in rainfall patterns and extreme weather events can reduce crop yields, sometimes dramatically. However, climate change can also offer new opportunities, by generating more favorable climatic conditions for agricultural production in certain regions that were previously less productive. In order to assess the positive and negative impacts of climate change on agriculture and identify effective adaptation strategies, scientists have produced massive amounts of data during the last two decades, conducting local experiments in agricultural plots and using models to simulate the effect of climate on crop yields. In most cases, these data are not pooled together and are analyzed separately by different groups of scientists to assess the effects of climate change at a local level, without any attempt to upscale the results at a larger scale. Yet, if brought together, these data represent a rich source of information that are relevant to analyze the effect of climate across diverse environmental conditions. The wealth of data available has led to the emergence of a new type of scientific activity, involving the retrieval of all available data on a given subject and their synthesis into more robust and generic results. In this talk, I review the statistical methods available to synthesize data generated in studies quantifying the effect of climate change on agriculture. I discuss both the most classic methods - such as meta-analysis - and more recent methods based on machine learning. In particular, I show how this approach can be used to map the impact of climate change on a large scale (national, continental and global) from local data. I illustrate these methods in several case studies and present several research perspectives in this area.
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    Benthic side control on the chemical composition of the ocean

    Date:
    07
    Sunday
    April
    2024
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Zvi Steiner
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: The sediment – bottom-water interface is suggested as a key control on the ch ... Read more The sediment – bottom-water interface is suggested as a key control on the chemical composition of the ocean by studies of trace elements in the ocean water-column, yet data regarding trace element fluxes and interactions taking place in the top ten cm of abyssal sediments are scarce. To bridge this gap, I analysed the trace and major element composition of porewater and sediment of red-clay sediment from the abyssal North Pacific, and hydrothermally influenced sediment from the Mid-Atlantic Ridge. The top sediment at both study regions is aerobic, nevertheless, there is large variability in the porewater concentrations of many elements at the top five cm. The North Pacific red-clay sediment is a source of cobalt, nickel, copper, arsenic, vanadium and barium to the deep-ocean, the magnitude of these fluxes is consistent with fluxes calculated based on the water-column distribution of most elements, and are equivalent to the global supply of these elements by rivers. The hydrothermally influenced sediment is a strong source of copper, zinc and cobalt up to three km from the vent due to oxidation of sulfide minerals. Close to the vents, the sediment is high in iron oxyhydroxides that adsorb the oxyanions vanadate, arsenate and phosphate, acting as a sink for these elements. The results of this study highlight the importance of red-clay sediment in shaping the chemical composition of the ocean, and suggest an important role for hydrothermally influenced sediment in modulating the contributions of hydrothermal vents to ocean biogeochemistry.
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    Large scale circulation adjustments to aerosol-cloud interactions and its radiative effect

    Date:
    31
    Sunday
    March
    2024
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Guy Dagan
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: The impact of anthropogenic aerosols on clouds is a leading source of uncertaint ... Read more The impact of anthropogenic aerosols on clouds is a leading source of uncertainty in estimating the effect of human activity on the climate system. The challenge lies in the scale difference between clouds (~1-10 km) and general circulation and climate (~1000 km). To address this, we utilize three different novel sets of simulations that allow to resolve convection while also including a epresentation of large-scale processes. Our findings demonstrate that aerosol-cloud interaction intensifies tropical overturning circulation. Employing a weak temperature gradient approximation, we attribute variations in circulation to clear-sky humidity changes driven by warm rain suppression by aerosols. In two sets of simulations accounting for sub-tropical-tropical coupling, we show that aerosol-driven sub-tropical rain suppression leads to increased advection of cold and moist air from the sub-tropics to the tropics, thus enhancing tropical cloudiness. The increased tropical cloudiness has a strong cooling effect by reflecting more of the incoming solar radiation. The classical “aerosol-cloud lifetime effect” is shown here to have a strong remote effect (sub-tropical aerosols increase cloudiness in the tropics), thus widening the concept of cloud adjustments to aerosol perturbation with important implications for marine cloud brightening.
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    EPS AI discussion seminar - Neural General Circulation Models for weather and climate predictions

    Date:
    25
    Monday
    March
    2024
    Lecture / Seminar
    Time: 16:00
    Location: also via zoom: https://weizmann.zoom.us/j/95890082380?pwd=TnZxc1NoSkxUbjM3SVB0dVpCdVRtZz09
    Lecturer: Janni Yuval
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il

    EPS Departmental Seminar; Challenges and opportunities in global storm resolving climate models

    Date:
    25
    Sunday
    February
    2024
    Lecture / Seminar
    Time: 11:00
    Title: EPS Departmental Seminar
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Ilai Guendelman
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il

    The geologic history of marine dissolved organic carbon from iron (oxyhydr)oxides

    Date:
    11
    Sunday
    February
    2024
    Lecture / Seminar
    Time: 11:00
    Title: EPS Department Seminar
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Nir Galili
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il

    The Southern Lights — Rhodopsin Complexes Discovered in an Algae Near Antarctica Can Help Unravel the Secrets of the Brain

    Date:
    16
    Monday
    October
    2023
    Colloquium
    Time: 11:00-12:15
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Moran Shalev-Benami
    Organizer: Department of Chemical and Structural Biology
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: Rhodopsins are a ubiquitous family of light sensing/signaling proteins. In recen ... Read more Rhodopsins are a ubiquitous family of light sensing/signaling proteins. In recent work, our group discovered an intriguing family of rhodopsins in algae: the bestrhodopsins. Through cryo-EM and comprehensive biochemical and electrophysiological studies, we showed that bestrhodopsins are fusions of rhodopsins and ion channels which assemble as mega-complexes to enable light-controlled passage of ions across membranes. Regulation of a classical ion channel by an attached photoreceptor has never been found before in nature, and previous attempts to engineer light-regulated fused channels have yielded limited success. The discovery and characterization of bestrhodopsins thus provide a new template for designing proteins with light-sensing and ion-conducting activities, as well as represent a platform for regulating cellular signaling in living organisms using light. These findings are therefore not only important as a basic scientific discovery but also for the field of optogenetics where neural activity is controlled by light. In the present talk, I will present the discovery of the bestrhodopsins, and explain how we use our cryo-EM work for structure-based design of dramatically improved tools to manipulate signaling cascades in cells by light control, paving the way for the next generation of optogenetics tools to study brain function in vivo.
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    Gallery: The Southern Lights — Rhodopsin Complexes Discovered in an Algae Near Antarctica Can Help Unravel the Secrets of the Brain Gallery
    The Southern Lights — Rhodopsin Complexes Discovered in an Algae Near Antarctica Can Help Unravel the Secrets of the Brain Colloquium website

    Quantifying the Global and Regional Contribution of Terrestrial Carbon Pools to the Land Sink

    Date:
    10
    Sunday
    September
    2023
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Yinon Bar-On
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: Terrestrial sequestration of carbon has mitigated ≈30% of anthropogenic carbo ... Read more Terrestrial sequestration of carbon has mitigated ≈30% of anthropogenic carbon emissions. However its distribution across different pools—live or dead biomass, and soil and sedimentary organic carbon— which has important implications for future climate change mitigation, remains uncertain. By analyzing global observational datasets of changes in terrestrial carbon pools, we are able to partition carbon that has been sequestered on land between 1992-2019 into live biomass and non-living organic carbon pools. We compare our observation-based estimates against predictions of global vegetation models and identify key processes that are not included in most models that can help align the models with observations. We find that most terrestrial carbon gains are sequestered as non-living organic matter, and thus more persistent than previously appreciated, with a substantial fraction linked to human activities such as river damming, wood harvest, and garbage disposal in landfills.
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    Ultra-Repellent Aerophilic Surfaces Underwater”

    Date:
    30
    Wednesday
    August
    2023
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Alexander B. Tesler
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Wetting describes the ability of liquids to maintain contact with a solid surfac ... Read more Wetting describes the ability of liquids to maintain contact with a solid surface, a phenomenon that is ubiquitous in nature.1 However, in engineering and medical applications, contact of solid surfaces with aqueous media leads to undesirable phenomena such as corrosion, chemo- and biofouling, which have extremely negative economic, health, and environmental impacts. Therefore, control of wetting on solid surfaces is key to mitigating its detrimental effects. The latter can be achieved by minimizing the contact of the solid substrate with aqueous media, so-called superhydrophobic surfaces (SHS). Although SHS have been studied for decades to overcome wetting challenges,2 they are still rarely used in engineering applications. When immersed underwater, a special type of SHS can trap air on its surface, so-called air plastron, also known as an aerophilic surface. To date, plastrons have been reported to be impractical for underwater engineering due to their short lifetime. Here, I will describe aerophilic surfaces made of titanium alloy (Ti) with an extended lifetime of plastron conserved for months underwater.3 The extended methodology was developed to unambiguously describe the wetting regime on such aerophilic surfaces since conventional goniometric measurements are simply impractical. My aerophilic surfaces drastically reduce the adhesion of blood, and when immersed in aqueous media, prevent the adhesion of bacteria, and marine organisms such as barnacles, and mussels. Applying thermodynamic stability theories, we describe a generic strategy to achieve long-term stability of plastron on aerophilic surfaces for demanding and hitherto unattainable applications. (1) Quéré, D. Wetting and Roughness. Annual Review of Materials Research 2008, 38 (1), 71-99. (2) Cassie, A. B. D.; Baxter, S. Wettability of porous surfaces. Transactions of the Faraday Society 1944, 40, 546-551. (3) Tesler, A.B.;* Kolle, S.; Prado, L.H.; Thievessen, I.; Böhringer, D.; Backholm, M.; Karunakaran, B.; Nurmi, H.A.; Latikka, M.; Fischer, L.; Stafslien, S.; Cenev, Z.M.; Timonen, J.V.I.; Bruns, M.; Mazare, A.; Lohbauer, U.; Virtanen, S.; Fabry, B.; Schmuki, P.; Ras, R.H.A.; Aizenberg, J.; Goldmann, W.H. Long-Lasting Aerophilic Metallic Surfaces Underwater. Nature Materials 2023, accepted. *Corresponding author
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    A Neolithic Tsunami Event along the Eastern Mediterranean Littoral: A Transdisciplinary Research at the Coast of Dor Israel

    Date:
    09
    Sunday
    July
    2023
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Gilad Steinberg
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: Tsunami events in antiquity had a profound influence on coastal societies. Six t ... Read more Tsunami events in antiquity had a profound influence on coastal societies. Six thousand years of historical records and geological data show that tsunamis are a common phenomenon affecting the eastern Mediterranean coastline. However, the possible impact of older tsunamis on prehistoric societies has not been investigated. Here we report, based on optically stimulated luminescence chronology, the earliest documented Holocene tsunami event, between 9.91 to 9.29 ka (kilo-annum), from the eastern Mediterranean at Dor, Israel. Tsunami debris from the early Neolithic is composed of marine sand embedded within fresh-brackish wetland deposits. Global and local sea-level curves for the period, 9.91–9.29 ka, as well as surface elevation reconstructions, show that the tsunami had a run-up of at least ~16 m and traveled between 3.5 to 1.5 km inland from the palaeo-coastline. Submerged slump scars on the continental slope, 16 km west of Dor, point to the nearby “Dor complex” as a likely cause. The near absence of Pre-Pottery Neolithic A-B archaeological sites (11.70–9.80 cal. ka) suggests these sites were removed by the tsunami, whereas younger, late Pre-Pottery Neolithic B-C (9.25–8.35 cal. ka) and later Pottery-Neolithic sites (8.25–7.80 cal. ka) indicate resettlement following the event. The significant run-up of this event highlights the disruptive impact of tsunamis on past societies along the Levantine coast.
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    Vision and AI

    Date:
    01
    Thursday
    June
    2023
    Lecture / Seminar
    Time: 12:15-13:15
    Title: Spaceborne multi-view computational tomography (CT)
    Location: Jacob Ziskind Building
    Lecturer: Yoav Schechner
    Organizer: Department of Computer Science and Applied Mathematics
    Contact: karina.avadia@weizmann.ac.il
    Abstract: We describe new computer vision tasks stemming from upcoming multiview tomograph ... Read more We describe new computer vision tasks stemming from upcoming multiview tomography from space. Solutions involve both novel imaging hardware and computational algorithms, based on machine learning and differential rendering. This can transform climate research and medical X-ray CT. The key idea is that advanced computing can enable computed tomography of volumetric scenes, based scattered radiation. We describe an upcoming space mission (CloudCT, funded by the ERC). It has 10 nano-satellites that will fly in an unprecedented formation, to capture the same scene (cloud fields) from multiple views simultaneously, using special cameras. The satellites and cameras are built now. They - and the algorithms - are specified to meet computer vision tasks, including geometric and polarimetric self-calibration in orbit, and estimation of 3D volumetric distribution of matter and microphysical properties. Deep learning and differential rendering enable analysis to scale to big data downlinked from orbit. Core ideas are generalized for medical X-ray imaging, to enable significant reduction of dose and acquisition time, while extracting chemical properties per voxel. The creativity of the computer vision and graphics communities can assist in critical needs for society, and this talk points out relevant challenges.
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    Determining past lake temperatures in saline lake systems using fluid inclusions: an example from the Dead Sea

    Date:
    21
    Sunday
    May
    2023
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Niels Brall
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: In recent decades, various temperature proxies have been developed and further e ... Read more In recent decades, various temperature proxies have been developed and further established in the scientific community, at both low and high accuracy, however, not every method can be applied without restriction to all minerals or rocks. Evaporitic rocks, for example, are abundant chemical sediments at the Earth's surface that are deposited from supersaturated brines in marine, terrestrial, and lacustrine environments. Halite is the most abundant rock-forming mineral in this group, which during crystal formation entraps tiny water droplets (fluid inclusions, FIs) that store the chemical composition of the parent brine at a specific pressure-temperature dependent density. Such FIs are therefore excellent records of the original physicochemical conditions of the source brine. Brillouin spectroscopy (BS) is a novel laser-based technique that uses density fluctuations in FIs to directly measure entrapment temperatures and thus the initial brine temperature during crystal growth. In this seminar, the BS method will be introduced and two application cases will be presented using salt layers from the Dead Sea which were deposited during two interglacial periods. In addition to the basic principles, both the recommended sampling strategy and pitfalls along with associated limitations will be presented. The conclusion will be that the salt layers commonly deposited in the Dead Sea basin consist of two types that formed preferentially in summer (coarse-grained crystals) and winter (fine-grained crystals), which is mainly controlled by the degree of salt saturation of the lake water. Furthermore, it will be shown how (1) lake bottom temperatures have fluctuated seasonally (summer/winter), and that (2) paleo temperature trends can be reconstructed for an entire halite layer that was deposited during holomictic periods in the Dead Sea basin. This method is particularly promising for evaporites that formed near the surface if the material has not been affected by external processes such as tectonic burial/uplift, erosion, or mineral replacement.
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    Projecting the impacts of climate change on human society

    Date:
    14
    Sunday
    May
    2023
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Ram Fishman
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il

    Mortality – and survival through microbial interactions - in abundant marine cyanobacteria

    Date:
    02
    Tuesday
    May
    2023
    Lecture / Seminar
    Time: 11:30-12:30
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Daniel Sher
    Organizer: Department of Plant and Environmental Sciences
    Contact: david.zeevi@weizmann.ac.il

    Oceanic Internal Gravity Waves: sources, sinks, and interactions with the eddy field. 

    Date:
    30
    Sunday
    April
    2023
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Roy Barkan
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: The global oceanic overturning circulation and the transport of heat and dissolv ... Read more The global oceanic overturning circulation and the transport of heat and dissolved gases are strongly controlled by upper ocean turbulent mixing that is driven by the breaking of internal gravity waves (IWs). Understanding the life cycle of oceanic IWs, from generation to dissipation, is therefore crucial for improving the representation of ocean mixing in climate models, which do not resolve the IW field.  Oceanic IWs are observed to have a continuous energy distribution across spatial and temporal scales – an internal wave continuum – despite being forced primarily at near-inertial and tidal frequencies at large scales. The formation of the IW continuum and the associated energy transfer to dissipative scales have been traditionally attributed to wave-wave interactions and to Doppler shifting of wave frequencies by currents. Here, we provide evidence from realistic numerical simulations that oceanic eddies rapidly diffuse storm-forced wave energy across spatiotemporal scales, thereby playing a dominant role in the formation of the IW continuum and the corresponding spatiotemporal distribution of energy dissipation. We further demonstrate that winds can play an important role in damping oceanic IWs through current feedback.  This results in a substantial reduction in wind power input at near inertial frequencies and a net energy sink for internal tides.
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    Innovation & Public Policy to Solve Climate Change

    Date:
    19
    Sunday
    March
    2023
    Lecture / Seminar
    Time: 13:00-14:00
    Title: SAERI - Sustainability and Energy Research Initiative Seminar Series
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Mr. Ram Amar
    Organizer: Feinberg Graduate School
    Contact: daphna.yahav@weizmann.ac.il
    Details: Host: Prof. Ron Milo The lecture will be held at the Benoziyo Biochemistry Buil ... Read more Host: Prof. Ron Milo The lecture will be held at the Benoziyo Biochemistry Building room 690
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    Reactive oxygen species regulation of cell to cell systemic signaling and acclimation in plants during stress

    Date:
    14
    Tuesday
    March
    2023
    Lecture / Seminar
    Time: 11:30-12:30
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Dr. Yosef Fichman
    Organizer: Department of Plant and Environmental Sciences
    Contact: merav.hagag@weizmann.ac.il
    Details: The lecture will be delivered at the Benoziyo Biochemistry Auditorium and via Zo ... Read more The lecture will be delivered at the Benoziyo Biochemistry Auditorium and via Zoom. For joining remotely, please use this link: https://weizmann.zoom.us/j/91945632908?pwd=ZmJseUdYYmlKQjN2K0ovREdpem1GUT09 Meeting ID: 919 4563 2908 Password: 350641
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    Abstract: Reactive oxygen species (ROS) play a key role in systemic cell to cell signaling ... Read more Reactive oxygen species (ROS) play a key role in systemic cell to cell signaling which is required for plant acclimation to different stresses, essential for the survival of plants. We recently developed a method to image real-time whole-plant accumulation of ROS and other systemic signals, and together with transcriptomic analysis and physiological measurements, we revealed the involvement of important signaling components in response to localized high light stress leading to systemic acquired acclimation (SAA) in Arabidopsis thaliana. The signal initiation and propagation maintenance are dependent on generation of ROS by RESPIRATORY BURST OXIDASE HOMOLOGS (RBOHs) in the apoplast and transport through the plasmodesmata, under the control of PLASMODESMATA LOCALIZED PROTEIN 1 (PDLP1) and PDLP5. Furthermore, we showed that phytochrome B acts in the same regulatory module as RBOHD and that it can regulate ROS production even if it is restricted to the cytosol. Additional proteins we discovered to function in the maintenance of the signal propagation, are aquaporin PLASMA INTRINSIC PROTEIN 2;1 (PIP2;1), that transport H2O2 across the plasma membrane and calcium channels including GLUTAMATE LIKE RECEPTORS 3.3 and 3.6 (GLR3.3 & GLR3.6), MECHANOSENSORS LIKE PROTEINS 2 and 3 (MSL2 & MSL3). Based on mutants and grafting experiments we identified the role of the ROS receptor HYDROGEN PEROXIDE INDUCED CALCIUM INCREASE 1 (HPCA1) in ROS cell to cell signal propagation, as well as the calcium signal propagation. We also reported that CALCINEURIN B-LIKE CALCIUM SENSOR 4 (CBL4), CBL4 INTERACTING PROTEIN KINASE 26 (CIPK26) and OPEN STOMATA 1 (OST1) are required for the cell-to-cell ROS signals. Altogether, screening more than 120 mutants, we shed light on the underling molecular mechanisms that coordinate the systemic cell to cell signals required for plant acclimation to stress. While most of our work focused on Arabidopsis, we were able to show the ROS auto propagation systemic signals are conserved in evolution and occur also in unicellular algae colonies, non-vascular plants and even mammalian cells. Thus, emphasizing the importance of the active process of cell-to-cell ROS signaling in communicating stress response signals between cells.
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    Ph.D. Defense Seminar -Temporal and spatial genetic diversity of a wild wheat population under climate change

    Date:
    06
    Monday
    March
    2023
    Lecture / Seminar
    Time: 15:00-16:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Tal Dahan-Meir
    Organizer: Department of Plant and Environmental Sciences
    Contact: tal.dahan@weizmann.ac.il

    Forecasting surface weather and storm tracks at one-month leads: role of the stratosphere and the Madden Julian Oscillation

    Date:
    05
    Sunday
    February
    2023
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Chaim Garfinkel
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: The traditional approach to weather forecasting on one- to two-week timescales u ... Read more The traditional approach to weather forecasting on one- to two-week timescales utilizes weather forecasting models, but on timescales longer than two weeks, the value of deterministic (or ensemble-based probabilistic) forecasts weakens. This is due to the presence of chaotic variability in the atmosphere. Yet certain modes of variability in the climate system have timescales longer than this two-week threshold, and the key to longer-scale prediction is to take advantage of these modes when they open up windows of opportunity. By understanding the impacts of these modes of variability on surface weather, the potential for improved forecasts on a monthly timescale can be demonstrated and eventually realized.  Two such classes of modes of variability are stratospheric variability (both in the tropical and polar stratosphere) and tropical tropospheric variability (e.g. the Madden-Julian Oscillation and El Nino). For example, both polar stratospheric sudden warmings and the Madden-Julian Oscillation have been shown to influence European and Mediterranean weather, but it is unclear (1) what mechanism(s) underlie these connections, (2) how far in advance the impacts can be predicted, (3) what governs the magnitude of the surface impact, and (4) how well models capture these connections. This talk will review progress made towards addressing these issues over the past several years in my group.
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    Silver mines, the rise of money and the advent of democracy

    Date:
    02
    Thursday
    February
    2023
    Lecture / Seminar
    Time: 14:00
    Title: EPS Department and Kimmel Center for Archaeological Science
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Prof. Francis Albarède
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: Over the last 2½ millenia, the world economy depended on prevailing currencies: ... Read more Over the last 2½ millenia, the world economy depended on prevailing currencies: the Athenian owl (530- 168 BCE), the Roman denarius (211 BCE-250 AD), the Spanish piece-of-eight (16th to 18th C), and today the US dollar. These reference monies were accepted everywhere and all, at least in the beginning, were made of silver. What is so special about this metal? Silver is useless and rare, but still abundant enough to match the wealth of nations and of their long-distance trade. Silver ores are associated with rare and recent tectonic environments, the Mediterranean world, notably the periphery of the Aegean Sea and Southern Iberia, and the American cordillera, Peru and Mexico. In contrast, they were markedly scarce in South and East Asia. After the virtual destruction of soils by the Anatolian farmers at the end of the Bronze Age, the Near and Middle East societies depended almost exclusively on the agriculture of Egypt and Mesopotamia. The Late Bronze Age collapse (ca. 1200 BCE) corresponded to the migration of Greek people and resulted in the annihilation of all the empires outside of the flood plains. Silver by weight was nevertheless used to save populations from famine and trade wheat, barley and copper. Military innovations, hoplites and their phalanx, were, with silver mines, the main resources of the Greeks. Mercenaries received their wages in silver, notably through the tributes exacted in silver by the Achaemenid (Persion) kings. By minting silver, the returning Greek mercenaries emerged as strong middle classes . They soon claimed their share of the power, toppled the tyrants, and installed democracy in many poleis from Greece and Southern Italy. Modern economics teaches us that egalitarian distribution of wealth is unfortunately unstable and this case is well illustrated by Syracuse. At the beginning of the common era, the Roman Empire found itself the owner of centuries of silver extracted from Greece and from Iberia. This bullion was used to buy luxury products, frankincense from Arabia, spices and cotton from India, ivory and precious wood from Africa. Leakage of silver towards the Indian Ocean was so strong that coins were quickly debased by copper and by 250 AD most of the silver had been lost. The progressive replacement of silver by a bimetallic system, gold for the rich and bronze for the working class, progressively fractured the society and ushered the brutal Middle Age regimes. Silver famine had finally destroyed the democratic ideal of the Greeks. This is food for thought as disappearing mining resources may severely affect our current vision of societies.
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    A meta'omics perspective on the functional potential and regulation of metabolic activity in the global ocean microbiome

    Date:
    31
    Tuesday
    January
    2023
    Lecture / Seminar
    Time: 11:30-12:30
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Shinichi Sunagawa
    Organizer: Department of Plant and Environmental Sciences
    Contact: david.zeevi@weizmann.ac.il
    Details: Host: Dr. David Zeevi

    Insolation Forcing and Eastern Mediterranean aridity: Evidence from the Dead Sea and implications for climate projections

    Date:
    29
    Sunday
    January
    2023
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Yochanan Kushnir
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: The Mediterranean region stands out among other subtropical regions in its proje ... Read more The Mediterranean region stands out among other subtropical regions in its projected drying response to the global rise in atmospheric greenhouse gas concentrations. This drying trend has already emerged out of the normal, random climate variability in the sensitive Eastern Mediterranean (EM) region. To better understand the dynamical mechanisms responsible for this regional sensitivity, we turn to past protracted EM drying states during warm geological epochs. A unique view of the historical and pre-historical hydroclimate of the EM-Levant has been gleaned from the continued study of the sedimentary and geochemical record left by the lakes that filled the tectonic basin of the Dead Sea. We revisit the Late Quaternary sediment record retrieved during the 2010-2011 Dead Sea Deep Drilling Project (DSDDP). The sediments clearly indicate that the Levant was drier during past warm interglacials than during the adjacent glacials but nonetheless experienced large variations in the intensity of the regional aridity. During each interglacial, extended thick deposits of salts accumulated at the Lake bottom, during millennia of significant regional aridity and severely reduced Mediterranean rains. These dry states were interrupted by extended wet intervals, fed by rains that were supplied by a blend of tropical and Mediterranean moisture. To understand the underlying causes of the EM-Levant interglacial hydroclimate variations, we put the Dead Sea record in the context of the Northern Hemisphere orbital insolation variations and their impact on the global climate system. We show that the changes in EM hydroclimate portrayed by the DSDDP record during the interglacials, are entirely consistent with the response of the North Atlantic Ocean and the overlying atmosphere and surrounding land areas to the changes in the latitudinal insolation gradient, as determined by climate models and evident by surface temperature proxies. This perspective provides new information regarding the dynamical processes responsible for the ongoing, greenhouse gas forced, EM drying.
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    Persistent and concurrent weather extremes in present and future climates

    Date:
    22
    Sunday
    January
    2023
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Kai Kornhuber
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: Recent severe summertime weather extremes in the Northern hemisphere extratropi ... Read more Recent severe summertime weather extremes in the Northern hemisphere extratropics such as the extraordinary 2021 North American Heatwave and the record-breaking floods in central Europe were in part driven by persistent circulation patterns in the tropospheric Jetstream. To what degree such circulation patterns will modulate extreme weather risk in a warming world is still uncertain and remains a highly debated topic in climate science. I will present results from recent studies that investigate physics of extraordinary extremes, future changes in weather persistence diagnosed by a feature tracking algorithm and future risks from concurrent extremes and associated impacts on crop production based on latest GGCMI-runs. A special emphasis will be placed on benchmarking the skill of CMIP5 and CMIP6 models to reproduce atmosphere dynamical mechanisms and associated extreme weather against reanalysis data short bio: Kai Kornhuber is an adjunct Associate Research Scientist at the Lamont-Doherty Earth Observatory, Columbia University in New York and a Senior Fellow on Climate Risks at the German Council on Foreign Relations. His research is concerned with physical drivers of extreme weather and climate events and associated societal impacts and risks under current and future climatic conditions. He is Founding Member of the EarthNetwork on Sustainable and Resilient Living in an Era of Increasing Disasters at Columbia’s Climate School, Co-Chair of the Compound Events Working Group at Risk-Kan, Steering Committee member of the HiWeather Project and a Co- Pi of the Project PERSEVERE within the BMBF Consortium.
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    The Israeli Climate Tech Ecosystem

    Date:
    15
    Sunday
    January
    2023
    Lecture / Seminar
    Time: 13:00-14:00
    Title: SAERI - Sustainability and Energy Research Initiative Seminar Series
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Mr. Uriel Klar
    Organizer: Feinberg Graduate School
    Contact: daphna.yahav@weizmann.ac.il

    Estimating Climate Change Mitigation Potential Through Dryland Forestation Actions

    Date:
    18
    Sunday
    December
    2022
    Lecture / Seminar
    Time: 13:00-14:00
    Title: SAERI - Sustainability and Energy Research Initiative Seminar Series
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Shani Rohatyn-Blitz, PhD
    Organizer: Feinberg Graduate School
    Contact: daphna.yahav@weizmann.ac.il

    Environmental viruses in biogeochemical cycles

    Date:
    22
    Tuesday
    November
    2022
    Lecture / Seminar
    Time: 11:30-12:30
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Dr. Ella Sieradzki
    Organizer: Department of Plant and Environmental Sciences
    Contact: david.zeevi@weizmann.ac.il
    Details: Host: Dr. David Zeevi
    Abstract: Viruses are the most abundant and diverse biological entities on Earth and can h ... Read more Viruses are the most abundant and diverse biological entities on Earth and can have a profound effect on biogeochemical cycles. In the sunlit ocean, viral lysis of 20-40% of hosts daily generates 20% of the dissolved organic carbon pool. Viruses can also affect their host’s metabolism during infection through expression of horizontally transferred host metabolic genes. While viruses in the ocean have been studied for over two decades, viral ecology and its effects have been neglected in other environments. I will present several of my studies that show how viruses in the ocean and in soil may affect their environment as well as ours through expression of metabolic genes and host-specific mortality. I’ll also discuss the current limitations in soil viral ecology, and technologies that can help us move forward.
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    What is the Science behind Climate Change?

    Date:
    22
    Tuesday
    November
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Peter Rez
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Not a day goes by when we don’t hear about the “climate crisis”; some effe ... Read more Not a day goes by when we don’t hear about the “climate crisis”; some effects are well documented, like the rise in the average global temperature and the shrinking of the polar ice caps. Undoubtedly, carbon dioxide levels in the atmosphere have been increasing, but what does “science” say about the potential consequences? The combination of the atmosphere, oceans, cryosphere and biosphere is the ultimate non-linear coupled complex system. How well do we understand what might happen? In the first part of my talk, I shall review my exploration of the original literature to try and separate out speculation, hypothesis, results of computational models, and most significantly actual observations. In the second part of my talk, I shall discuss what will actually work to reduce carbon dioxide emissions (complete elimination or Net Zero is an impossibility). Although it has become fashionable for governments to impose mandates enshrined in laws, the only laws that matter are the laws of thermodynamics and Ohm’s law.
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    TBA - M. Magaritz Memorial Lecture: Climate Intervention

    Date:
    20
    Sunday
    November
    2022
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: David Fahey
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il

    Climate change challenge and innovative approaches - from batteries to agriculture - towards a more sustainable future

    Date:
    08
    Tuesday
    November
    2022
    Lecture / Seminar
    Time: 09:30
    Location: Dolfi and Lola Ebner Auditorium
    Lecturer: Steven Chu
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il

    How members of the public can engage in effective political action for the climate

    Date:
    04
    Sunday
    September
    2022
    Lecture / Seminar
    Time: 18:00-19:00
    Title: SAERI Zoom Lecture- Sustainability and Energy Research Initiative lecture series
    Location: lecture delivered via Zoom
    Lecturer: Dr. Seth Wynes
    Organizer: Feinberg Graduate School
    Contact: daphna.yahav@weizmann.ac.il
    Details: Host: Prof. Ron Milo, SAERI Scientific Director The lecture will take plac ... Read more Host: Prof. Ron Milo, SAERI Scientific Director The lecture will take place via Zoom: https://weizmann.zoom.us/j/95853366895?pwd=WCtXZVlicCt5ZjByRkZYL3hoRjZ5dz09 Meeting ID: 958 5336 6895 Password: 12345
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    How microbial interactions shape the exo-metabolic landscape of the ocean

    Date:
    12
    Tuesday
    July
    2022
    Lecture / Seminar
    Time: 11:30-12:30
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Dr. Constanze Kuhlisch
    Organizer: Department of Plant and Environmental Sciences
    Contact: david.zeevi@weizmann.ac.il
    Details: Host: Prof. Assaf Vardi
    Abstract: Algal blooms are events of high primary productivity and rapid population growth ... Read more Algal blooms are events of high primary productivity and rapid population growth that can cover vast oceanic regions. They thus play an important role for the marine food web and for the global carbon and sulfur cycling. Furthermore, algal blooms are hotspots of microbial interactions with e.g. grazers, heterotrophic bacteria, fungi and viruses. These interactions are mediated by metabolite signals, they can modulate metabolic pathways and can induce biosynthetic gene clusters – the diversity of microbial communities in natural blooms is thus crucial in understanding the chemical ecology of algal blooms. In my talk, I will show how lipid remodeling during the infection of E. huxleyi blooms by its giant virus imprints the marine dissolved organic matter pool. Further, I will present how a tripartite interaction between alga, virus and associated microbes leads to a unique halogenation activity during bloom demise. Lastly, I will discuss the potential ecological role of indole derivatives that accumulate in the blooms of E. huxleyi.
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    Complex biogenic crystals made by unicellular algae are constructed with simple principles

    Date:
    29
    Tuesday
    March
    2022
    Lecture / Seminar
    Time: 11:30-12:30
    Title: Member Seminar
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Emanuel Avrahami
    Organizer: Department of Plant and Environmental Sciences
    Contact: david.zeevi@weizmann.ac.il
    Details: Host: Dr. Assaf Gal
    Abstract: Coccoliths are exoskeletal plates, made of highly complex microscopic calcite (C ... Read more Coccoliths are exoskeletal plates, made of highly complex microscopic calcite (CaCO3) crystals with astonishing morphological variety, produced by unicellular algae called Coccolithophores. For decades, their complexity has made coccolith fabrication and its controls alluring to scientists from different fields. Coccoliths grow intracellularly in a specialized vesicle where they presumably interact with chiral additives in a stereospecific manner. Such specific interactions are thought to give rise to numerous crystallographic faces, that convey ultrastructural chirality and convolutedness. We investigated the large coccoliths of Calcidiscus leptoporus by extracting them from within the cells along their growth, imagining them with various electron microscopy techniques at high resolution, and rendering their 3D structure. Our morphological analysis revealed that as the crystals mature, they transition from isotropic rhombohedra to highly anisotropic shapes, while expressing only a single set of crystallographic faces. This observation profoundly challenges the involvement of chiral modifiers. The crystals’ growth pattern showed that their shape is attained via differential growth rates of symmetry related facets with. Additionally, the rhombohedral geometry of the crystals appears to convey ultrastructural chirality in initial coccolith assembly stages. These findings change our understanding of biological control over complex crystal construction and mechanistically simplify the system in which they emerge.
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    Decadal Climate Predictions Using Sequential Learning Algorithms

    Date:
    27
    Sunday
    March
    2022
    Lecture / Seminar
    Time: 11:00
    Location: https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer: Golan Bel
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: Decadal Climate Predictions Using Sequential Learning Algorithms Ensembles of c ... Read more Decadal Climate Predictions Using Sequential Learning Algorithms Ensembles of climate models are commonly used to improve climate predictions and assess the uncertainties associated with them. Weighting the models according to their performances holds the promise of further improving their predictions. Using an ensemble of climate model simulations from the CMIP5 decadal experiments, we quantified the total uncertainty associated with these predictions and the relative importance of model and internal uncertainties. Sequential learning algorithms (SLAs) were used to reduce the forecast errors and reduce the model uncertainties. The reliability of the SLA predictions was also tested, and the advantages and limitations of the different performance measures are discussed. The spatial distribution of the SLAs performance showed that they are skillful and better than the other forecasting methods over large continuous regions. This finding suggests that, despite the fact that each of the ensemble models is not skillful, the models were able to capture some physical processes that resulted in deviations from the climatology and that the SLAs enabled the extraction of this additional information. If time permits I will also present a method for estimating the uncertainties associated with ensemble predictions and demonstrate the resulting improved reliability. References: 1. Improvement of climate predictions and reduction of their uncertainties using learning algorithms, Atmospheric Chemistry and Physics 15, 8631-8641 (2015). 2. Decadal climate predictions using sequential learning algorithms, Journal of Climate 29, 3787-3809 (2016). 3. The contribution of internal and model variabilities to the uncertainty in CMIP5 decadal climate predictions, Climate Dynamics 49, 3221 (2017). 4. Quantifying the uncertainties in an ensemble of decadal climate predictions. Journal of Geophysical Research: Atmospheres 122, 13,191–13,200 (2017). 5. Learning algorithms allow for improved reliability and accuracy of global mean surface temperature projections. Nature Communications 11, 451 (2020).
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    A geologic perspective on anthropogenic climate change

    Date:
    20
    Sunday
    March
    2022
    Lecture / Seminar
    Time: 13:00-14:00
    Title: SAERI ZOOM Lecture- Sustainability and Energy Research Initiative lecture series
    Location: via Zoom only
    Lecturer: Prof. Itay Halevy
    Organizer: Feinberg Graduate School
    Contact: daphna.yahav@weizmann.ac.il
    Details: Host: Prof. Ron Milo, SAERI Scientific Director The lecture will take place ... Read more Host: Prof. Ron Milo, SAERI Scientific Director The lecture will take place via Zoom only: https://weizmann.zoom.us/j/96305565579?pwd=eFpQSWwwSVp6STZTMnMyV1hTb2RvZz09 Meeting ID: 963 0556 5579 Password: 12345
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    Four disruptive technologies that are revolutionizing sensing of the oceans

    Date:
    20
    Sunday
    March
    2022
    Lecture / Seminar
    Time: 11:00
    Location: Sussman Family Building for Environmental Sciences
    Lecturer: Emmanuel Boss
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: The maker movement (cheap electronics + sharing), automated microscopy, autonom ... Read more The maker movement (cheap electronics + sharing), automated microscopy, autonomous platforms and small footprint satellites have been revolutionizing oceanography, opening a variety of new avenues for research and requiring a different education model. In this talk I will summarize a few activities my lab has been involved in that are associated with these disruptive technologies and why I am very optimistic for the future of our field in the coming years.
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    Sediment geochemistry in large lakes, and what it can tell us about the ancient oceans

    Date:
    27
    Sunday
    February
    2022
    Lecture / Seminar
    Time: 11:00
    Location: https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer: Sergei Katsev
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: The Great Lakes of the Earth are freshwater seas, and many of the geochemical pr ... Read more The Great Lakes of the Earth are freshwater seas, and many of the geochemical processes that take place in their bottom sediments parallel those that happen in marine environments. The conditions, however, are different enough to significantly modify the geochemical cycles of key elements. By analyzing those differences, we can not only understand the functioning of the planet's largest freshwater ecosystems, but can also gain insight into the elemental cycling (C, N, P, S...) in the oceans during the past geological epochs.
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    Diverse mechanisms of adaptive flexibility discovered by multi-species analysis of stomatal development

    Date:
    24
    Thursday
    February
    2022
    Lecture / Seminar
    Time: 11:30-12:30
    Location: https://weizmann.zoom.us/j/98989152393?pwd=a050Mm4rSlEwb2hLN1FiKy9oT24xdz09 Password: 002663
    Lecturer: Dr. Ido Nir
    Organizer: Department of Plant and Environmental Sciences
    Contact: merav.hagag@weizmann.ac.il
    Details: Host: Prof. Asaph Aharoni
    Abstract: An essential trait of plants is the ability to change intrinsic programs to alig ... Read more An essential trait of plants is the ability to change intrinsic programs to align with external signals. Plants can sense their environment and respond by refining their development program. A good example of sensing and response is the behavior of stomata. Plant stomata optimize the assimilation of carbon dioxide (CO2) for use in photosynthesis while minimizing water loss. They do this in two ways: by physiological control of when they are open or closed and by developmental regulation of their abundance and pattern. Both modes of control can be regulated by the environment, and as we face future climate change, with an increase in average global temperatures and water limitation, the understanding of how plants optimize stomatal production and patterns with the environment has fundamental importance. Our fullest understanding of the genetic control of stomatal development is from work in Arabidopsis. Here, development involves a core set of transcription factors whose expression and activity are regulated by signals from neighbor cells, from distant parts of the plant and from environmental cues like light, temperature, osmotic stress, and CO2 levels. But while Arabidopsis is a powerful model for stomatal development, this research showed that tomatoes often lean on different cellular and genetic strategies to achieve optimal stomatal distributions. Using novel genetically encoded reporters and custom microscopy for developmental time-course analysis, we found that, like in Arabidopsis, tomato undergoes a series of asymmetric and symmetric cell divisions to produce stomata. However, we found that not all asymmetric divisions (ACDs) are the same; certain classes of ACDs are missing in the tomato epidermis, and instead other types of ACDs are used to generate non-stomatal cells. ACDs have been shown in both plant and animal systems to enable tunable development. This findings in tomato indicate that there are new types of ACDs that could mediate species-specific control of cell production and tissue organization.
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    Distributed views across media: From space to ocean-depths

    Date:
    13
    Sunday
    February
    2022
    Lecture / Seminar
    Time: 11:00
    Location: https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer: Yoav Schechner
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: By economy of scale, imaging sensors can now be deployed densely and operated in ... Read more By economy of scale, imaging sensors can now be deployed densely and operated in a coordinated manner at large numbers in space, air, underwater and on the ground. Such distributed imaging systems enable multi-view setups across heterogeneous media of importance to geoscience. These create new observation modes. One outcome is 4D volumetric spatiotemporal recovery of scatterers in the atmosphere, specifically cloud content (the core of the CloudCT space mission). This is in addition to computed tomography of underwater sediment suspension and atmospheric turbulence distributions. We describe several such systems - demonstrated in the field, including both distributed imaging and the basis of the algorithms to analyze the data.
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    Agricultural strategies, subsistence and climate of Indus and subsequent cultures (~2900 BCE-1800 CE) from north-western India

    Date:
    10
    Thursday
    February
    2022
    Lecture / Seminar
    Time: 11:30-12:30
    Lecturer: Dr. Shalini Sharma
    Organizer: Scientific Archeology Unit
    Contact: lior.regev@weizmann.ac.il
    Details: Join Zoom Meeting https://weizmann.zoom.us/j/6168548886 Meeting ID: 616-854-88 ... Read more Join Zoom Meeting https://weizmann.zoom.us/j/6168548886 Meeting ID: 616-854-8886 Meeting password: 976012
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    Agricultural strategies, subsistence and climate of Indus and subsequent cultures (~2900 BCE-1800 CE) from north-western India Lecture / Seminar website

    Amplified warming of extreme temperatures over tropical land

    Date:
    08
    Tuesday
    February
    2022
    Lecture / Seminar
    Time: 11:00
    Location: https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer: Michael P. Byrne
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: Extreme temperatures have warmed substantially over recent decades and are expec ... Read more Extreme temperatures have warmed substantially over recent decades and are expected to continue warming in response to future climate change. Warming of extreme temperatures is projected to be amplified over land, with severe implications for human health, wildfire risk and food production. Using simulations from coupled climate models, I show that hot days over tropical land warm substantially more than the average day. For example, warming of the hottest 5% of land days is a factor of 1.2 larger than the time-mean warming averaged across models. The climate-change response of extreme temperatures over tropical land is interpreted using a theory based on convective coupling and the weak temperature gradient approximation. According to the theory, warming is amplified for hot land days because those days are dry: this is termed the “drier get hotter” mechanism. Changes in near-surface relative humidity further increase tropical land warming, with decreases in land relative humidity particularly important. The theory advances physical understanding of the tropical climate and highlights climatological land-surface dryness as a key factor determining how extreme temperatures respond to climate change.
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    M. Magaritz Memorial Lecture: The storyline approach to the construction of useable climate information at the local scale.

    Date:
    01
    Tuesday
    February
    2022
    Lecture / Seminar
    Time: 11:00
    Lecturer: Ted Shepherd
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Details: The standard approach to the production of climate information is probabilistic ... Read more The standard approach to the production of climate information is probabilistic in nature, with quantified uncertainties. There is a growing awareness of the limitations of this approach from the perspective of practical useability for decision-making, which has led to the emergence of more narrative-based or ‘storyline’ approaches. In this talk I will explain the rationale behind the storyline approach to the construction of useable climate information at the local scale, and discuss how it can be used to frame climate evidence in the context of adaptation.
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    Stormy weather: past and future hazards from a weather system perspective

    Date:
    23
    Sunday
    January
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer: Jennifer Catto
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: Natural hazards such as extreme wind, rainfall and ocean waves can have severe i ... Read more Natural hazards such as extreme wind, rainfall and ocean waves can have severe impacts on built and natural environments, contributing to the occurrence of disastrous events in some cases. These hazards are often caused by weather systems such as cyclones, fronts and thunderstorms. We have used a number of objective techniques to identify these weather system types, in order to understand the links between the weather systems and hazards in observations. We have then used this understanding to evaluate climate models and to better understand the response of the weather systems and the high impact hazards to a warmer climate.
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    Three arguments for increasing weather persistence in boreal summer – and why we should care.

    Date:
    11
    Tuesday
    January
    2022
    Lecture / Seminar
    Time: 11:00
    Location: https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer: Dim Coumou
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: Persistent summer weather can have significant socio-economic impacts. Prolonged ... Read more Persistent summer weather can have significant socio-economic impacts. Prolonged hot-dry conditions may lead to crop yield losses, while consecutive rainy days (e.g. associated with stalling cyclones) can cause flooding. Both observational and climate model analyses indicate that global warming weakens the hemispheric-wide circulation in boreal summer, yet it is still largely unclear what this weakening implies for the persistence of regional weather conditions. Here, I present multiple lines of evidence supporting that weather persistence in summer has been increasing over the last 40 years over most mid-latitude regions and will continue to do so under future global warming. Methodologically, we use a persistence metric rooted in dynamical systems theory, which does not require partitioning instantaneous atmospheric states in an arbitrary number of clusters. This makes it ideally suited to detect subtle changes in atmospheric motions including weather-persistence. I discuss relevant recent literature and argue that there is now substantial evidence for increasing weather persistence over mid-latitude regions, providing enhanced extreme weather risks for society.
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