The CALIPSO Mission

Aerosols and clouds have important effects on Earth's climate through their effects on the radiation budget and the cycling of water between the atmosphere and Earth's surface. Limitations in our understanding of the global distribution and properties of aerosols and clouds are partly responsible for the current uncertainties in modeling the global climate system and predicting climate change. The CALIPSO satellite was developed as a joint project between NASA and the French space agency CNES to provide needed capabilities to observe aerosols and clouds from space. CALIPSO carries CALIOP, a two-wavelength, polarization-sensitive lidar, along with two passive sensors operating in the visible and thermal infrared spectral regions. CALIOP is the first lidar to provide long-term atmospheric measurements from Earth's orbit. Its profiling and polarization capabilities offer unique measurement capabilities. Launched together with the CloudSat satellite in April 2006 and now flying in formation with the A-train satellite constellation, CALIPSO is now providing information on the distribution and properties of aerosols and clouds, which is fundamental to advancing our understanding and prediction of climate. This paper provides an overview of the CALIPSO mission and instruments, the data produced, and early results.

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Long-term thermal sensitivity of Earth’s tropical forests

Science ◽

10.1126/science.aaw7578 ◽

2020 ◽

Vol 368 (6493) ◽

pp. 869-874 ◽

Cited By ~ 22

Author(s):

Martin J. P. Sullivan ◽

Simon L. Lewis ◽

Kofi Affum-Baffoe ◽

Carolina Castilho ◽

Flávia Costa ◽

...

Keyword(s):

Tropical Forests ◽

Climate Adaptation ◽

Global Climate ◽

Thermal Sensitivity ◽

Forest Carbon ◽

Maximum Temperature ◽

Permanent Plots ◽

Short Term ◽

Earth’S Climate

The sensitivity of tropical forest carbon to climate is a key uncertainty in predicting global climate change. Although short-term drying and warming are known to affect forests, it is unknown if such effects translate into long-term responses. Here, we analyze 590 permanent plots measured across the tropics to derive the equilibrium climate controls on forest carbon. Maximum temperature is the most important predictor of aboveground biomass (−9.1 megagrams of carbon per hectare per degree Celsius), primarily by reducing woody productivity, and has a greater impact per °C in the hottest forests (>32.2°C). Our results nevertheless reveal greater thermal resilience than observations of short-term variation imply. To realize the long-term climate adaptation potential of tropical forests requires both protecting them and stabilizing Earth’s climate.

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Closing the water cycle from observations across scales: Where do we stand?

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-19-0316.1 ◽

2021 ◽

pp. 1-95

Author(s):

Wouter Dorigo ◽

Stephan Dietrich ◽

Filipe Aires ◽

Luca Brocca ◽

Sarah Carter ◽

...

Keyword(s):

Hydrological Cycle ◽

Water Cycle ◽

Global Climate ◽

Spatial Scales ◽

Spatial And Temporal Scales ◽

Mitigation And Adaptation ◽

Consistent Assessment ◽

Earth’S Climate ◽

Improved Model

AbstractLife on Earth vitally depends on the availability of water. Human pressure on freshwater resources is increasing, as is human exposure to weather-related extremes (droughts, storms, floods) caused by climate change. Understanding these changes is pivotal for developing mitigation and adaptation strategies. The Global Climate Observing System (GCOS) defines a suite of Essential Climate Variables (ECVs), many related to the water cycle, required to systematically monitor the Earth's climate system. Since long-term observations of these ECVs are derived from different observation techniques, platforms, instruments, and retrieval algorithms, they often lack the accuracy, completeness, resolution, to consistently to characterize water cycle variability at multiple spatial and temporal scales.Here, we review the capability of ground-based and remotely sensed observations of water cycle ECVs to consistently observe the hydrological cycle. We evaluate the relevant land, atmosphere, and ocean water storages and the fluxes between them, including anthropogenic water use. Particularly, we assess how well they close on multiple temporal and spatial scales. On this basis, we discuss gaps in observation systems and formulate guidelines for future water cycle observation strategies. We conclude that, while long-term water-cycle monitoring has greatly advanced in the past, many observational gaps still need to be overcome to close the water budget and enable a comprehensive and consistent assessment across scales. Trends in water cycle components can only be observed with great uncertainty, mainly due to insufficient length and homogeneity. An advanced closure of the water cycle requires improved model-data synthesis capabilities, particularly at regional to local scales.

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Simulating glacial dust changes in the Southern Hemisphere using ECHAM6.3-HAM2.3

10.5194/cp-2021-73 ◽

2021 ◽

Author(s):

Stephan Krätschmer ◽

Michelle van der Does ◽

Frank Lamy ◽

Gerrit Lohmann ◽

Christoph Völker ◽

...

Keyword(s):

Southern Hemisphere ◽

Mineral Dust ◽

Global Climate ◽

Ice Core ◽

Radiation Budget ◽

Dust Particles ◽

Meridional Transport ◽

Climate Conditions ◽

Earth’S Climate ◽

Long Timescales

Abstract. Mineral dust aerosol constitutes an important component of the Earth’s climate system, not only on short timescales due to direct and indirect influences on the radiation budget, but also on long timescales by acting as a fertilizer for the biosphere and thus affecting the global carbon cycle. For a quantitative assessment of its impact on the global climate, state-of-the-art atmospheric and aerosol models can be utilized. In this study, we use the ECHAM6.3-HAM2.3 model to perform global simulations of the mineral dust cycle for present-day (PD), pre-industrial (PI) and Last Glacial Maximum (LGM) climate conditions. The intercomparison with marine sediment and ice core data as well as other modeling studies shows that the obtained annual dust emissions of 1221, 923 and 5159 Tg for PD, PI and LGM, respectively, generally agree well with previous findings. Our analyses focussing on the Southern Hemisphere suggest that over 90 % of the mineral dust deposited over Antarctica are of Australian or South American origin during both PI and LGM. However, contrary to previous studies, we find that Australia contributes a higher proportion during the LGM, which is mainly caused by changes in the precipitation patterns. Obtained increased particle radii during the LGM can be traced back to increased sulphate condensation on the particle surfaces as a consequence of longer particle lifetimes. The meridional transport of mineral dust from its source regions to the South Pole takes place at different altitudes, depending on the grain size of the dust particles. We find a trend of generally lower transport heights during the LGM compared to PI as a consequence of reduced convection due to colder surfaces, indicating a vertically less extensive Polar Cell.

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The 3.6-Ma aridity and westerlies history over midlatitude Asia linked with global climatic cooling

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1922710117 ◽

2020 ◽

Vol 117 (40) ◽

pp. 24729-24734

Author(s):

Xiaomin Fang ◽

Zhisheng An ◽

Steven C. Clemens ◽

Jinbo Zan ◽

Zhengguo Shi ◽

...

Keyword(s):

Land Surface ◽

Global Climate ◽

Dust Emission ◽

Taklimakan Desert ◽

Positive Feedbacks ◽

Eolian Dust ◽

Dust Flux ◽

Global Cooling ◽

Earth’S Climate

Midlatitude Asia (MLA), strongly influenced by westerlies-controlled climate, is a key source of global atmospheric dust, and plays a significant role in Earth’s climate system . However, it remains unclear how the westerlies, MLA aridity, and dust flux from this region evolved over time. Here, we report a unique high-resolution eolian dust record covering the past 3.6 Ma, retrieved from the thickest loess borehole sequence (671 m) recovered to date, at the southern margin of the Taklimakan desert in the MLA interior. The results show that eolian dust accumulation, which is closely related to aridity and the westerlies, indicates existence of a dry climate, desert area, and stable land surface, promoting continuous loess deposition since at least ∼3.6 Ma. This region experienced long-term stepwise drying at ∼2.7, 1.1, and 0.5 Ma, coeval with a dominant periodicity shift from 41-ka cyclicity to 100-ka cyclicity between 1.1 Ma and 0.5 Ma. These features match well with global ice volume variability both in the time and frequency domains (including the Mid-Pleistocene Transition), highlighting global cooling-forced aridity and westerlies climate changes on these timescales. Numerical modeling demonstrates that global cooling can dry MLA and intensify the westerlies, which facilitates dust emission and transport, providing an interpretive framework. Increased dust may have promoted positive feedbacks (e.g., decreasing atmospheric CO2 concentrations and modulating radiation budgets), contributing to further cooling. Unraveling the long-term evolution of MLA aridity and westerlies climate is an indispensable component of the unfolding mystery of global climate change.

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A breviary of Earth’s climate changes using Stephan-Boltzmann law

10.20937/atm.53102 ◽

2021 ◽

Author(s):

Guillermo Nicolás Murray Tortarolo

Keyword(s):

Climate Changes ◽

Global Climate ◽

Analytical Framework ◽

Global Temperature ◽

Radiation Budget ◽

Snowball Earth ◽

Thermal Maximum ◽

History Of ◽

Earth’S Climate ◽

Boltzmann Law

Earth’s surface temperature oscillated greatly throughout time. From near congelation during “snowball Earth” 2.9Gya to an ice-free world in the Paleocene-Eocene Thermal maximum 55Mya. These changes have been forced by internal (e.g. changes in the chemical composition of the atmosphere) or external (e.g. changes in solar luminosity) drivers that varied through time. Thus, if we understand how the radiation budget evolved in different times, we can closely calculate past global climate; a fundamental comparison to situate current climate change in the context Earth’s history. Here I present an analytical framework employing a simple energy balance derived from the Stephan-Boltzmann law, that allows for quick comparison between drivers of global temperature and at multiple moments in the history of our planet. My results show that current rates of increase in global temperature are at least four times faster than any previous warming event.

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A Determination of the Cloud Feedback from Climate Variations over the Past Decade

Science ◽

10.1126/science.1192546 ◽

2010 ◽

Vol 330 (6010) ◽

pp. 1523-1527 ◽

Cited By ~ 141

Author(s):

A. E. Dessler

Keyword(s):

Climate Models ◽

Short Wave ◽

Cloud Feedback ◽

Radiation Budget ◽

Climate Variations ◽

Short Term ◽

Positive Feedbacks ◽

Short And Long Term ◽

Earth’S Climate

Estimates of Earth's climate sensitivity are uncertain, largely because of uncertainty in the long-term cloud feedback. I estimated the magnitude of the cloud feedback in response to short-term climate variations by analyzing the top-of-atmosphere radiation budget from March 2000 to February 2010. Over this period, the short-term cloud feedback had a magnitude of 0.54 ± 0.74 (2σ) watts per square meter per kelvin, meaning that it is likely positive. A small negative feedback is possible, but one large enough to cancel the climate’s positive feedbacks is not supported by these observations. Both long- and short-wave components of short-term cloud feedback are also likely positive. Calculations of short-term cloud feedback in climate models yield a similar feedback. I find no correlation in the models between the short- and long-term cloud feedbacks.

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LIME: the Lunar Irradiance Model of the European Space Agency

10.5194/egusphere-egu21-10066 ◽

2021 ◽

Author(s):

Sarah Taylor ◽

Stefan Adriaensen ◽

Carlos Toledano ◽

África Barreto ◽

Emma Woolliams ◽

...

Keyword(s):

Near Infrared ◽

Dynamic Range ◽

Time Window ◽

Global Climate ◽

Thermal Sensitivity ◽

European Space Agency ◽

Absolute Calibration ◽

Calibration Source ◽

Space Agency

Absolute calibration of Earth observation sensors is key to ensuring long term stability and interoperability, essential for long term global climate records and forecasts. The Moon provides a photometrically stable calibration source, within the range of the Earth radiometric levels, and is free from atmospheric interference. However, to use this ideal calibration source, one must model the variation of its disk integrated irradiance resulting from changes in Sun-Earth-Moon geometries.LIME, the Lunar Irradiance Model of the European Space Agency, is a new lunar irradiance model developed from ground-based observations acquired using a lunar photometer operating from the Iza&#241;a Atmospheric Observatory and Teide Peak, Tenerife. Approximately 300 lunar observations acquired between March 2018 and October 2020 currently contribute to the model, which builds on the widely-used ROLO (Robotic Lunar Observatory) model.This presentation will outline the strategy used to derive LIME. First, the instrument was calibrated traceably to SI and characterised to determine its thermal sensitivity and its linearity over the wide dynamic range required. Second, the instrument was installed at the observatory, and nightly observations over a two-hour time window were extrapolated to provide top-of-atmosphere lunar irradiance using the Langley plot method. Third, these observations were combined to derive the model. Each of these steps includes a metrologically rigorous uncertainty analysis.Comparisons to several EO sensors will be presented including Proba-V, Pleiades and Sentinel 3A and 3B, as well as a comparison to GIRO, the GSICS implementation &#160;&#160;of the ROLO model. Initial results indicate LIME predicts 3% - 5% higher disk integrated lunar irradiance than the GIRO/ROLO model for the visible and near-infrared channels. The model has an expanded (k = 2) absolute radiometric uncertainty of ~2%, and it is expected that planned observations until at least 2024 will further constrain the model in subsequent updates.

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On Climate Change Risks of Long-Term Socio-Economic Development in Russia

Russian Economic Journal ◽

10.33983/0130-9757-2019-5-79-95 ◽

2019 ◽

pp. 79-95

Author(s):

N.E. Terentiev

Keyword(s):

Climate Change ◽

Economic Development ◽

Technological Innovation ◽

Global Climate Change ◽

Global Climate ◽

Climate Risk ◽

Climate Change Risks ◽

Socio Economic Development ◽

Management Policies

Based on the latest data, paper investigates the dynamics of global climate change and its impact on economic growth in the long-term. The notion of climate risk is considered. The main directions of climate risk management policies are analyzed aimed, first, at reducing anthropogenic greenhouse gas emissions through technological innovation and structural economic shifts; secondly, at adaptation of population, territories and economic complexes to the irreparable effects of climate change. The problem of taking into account the phenomenon of climate change in the state economic policy is put in the context of the most urgent tasks of intensification of long-term socio-economic development and parrying strategic challenges to the development of Russia.

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Monitoring Effects of Catchment Management Practices on Phosphorus Loads into the Eutrophic Peel-Harvey Estuary, Western Australia

Water Science & Technology ◽

10.2166/wst.1986.0180 ◽

1986 ◽

Vol 18 (4-5) ◽

pp. 53-61 ◽

Cited By ~ 4

Author(s):

P. B. Birch ◽

G. G. Forbes ◽

N. J. Schofield

Keyword(s):

Management Practices ◽

Major Change ◽

High Flow ◽

Catchment Management ◽

Flow Rates ◽

Early Results ◽

Phosphorus Loads ◽

Time Of Year ◽

High Runoff

Early results from monitoring runoff suggest that the programme to reduce application of superphosphate to farmlands in surrounding catchments has been successful in reducing input of phosphorus to the eutrophic Peel-Harvey estuary. In the estuary this phosphorus fertilizes algae which grow in abundance and accumulate and pollute once clean beaches. The success of the programme has been judged from application of an empirical statistical model, which was derived from 6 years of data from the Harvey Estuary catchment prior to a major change in fertilizer practices in 1984. The model relates concentration of phosphorus with rate of flow and time of year. High phosphorus concentrations were associated with high flow rates and with flows early in the high runoff season (May-July). The model predicted that the distribution of flows in 1984 should have resulted in a flow-weighted concentration of phosphorus near the long-term average; the observed concentration was 25% below the long-term average. This means that the amount of phosphorus discharged into the Harvey Estuary could have been about 2 5% less than expected from the volume of runoff which occurred. However several more years of data are required to confirm this trend.

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Chilling Out

10.1093/oso/9780198717867.003.0010 ◽

2018 ◽

Author(s):

Roy Livermore

Keyword(s):

Plate Tectonics ◽

Volcanic Eruptions ◽

Atmospheric Temperature ◽

Ocean Currents ◽

Mountain Ranges ◽

Continental Rifts ◽

Earth’S Climate ◽

The One ◽

Tectonic Forces

The Earth’s climate changes naturally on all timescales. At the short end of the spectrum—hours or days—it is affected by sudden events such as volcanic eruptions, which raise the atmospheric temperature directly, and also indirectly, by the addition of greenhouse gases such as water vapour and carbon dioxide. Over years, centuries, and millennia, climate is influenced by changes in ocean currents that, ultimately, are controlled by the geography of ocean basins. On scales of thousands to hundreds of thousands of years, the Earth’s orbit around the Sun is the crucial influence, producing glaciations and interglacials, such as the one in which we live. Longer still, tectonic forces operate over millions of years to produce mountain ranges like the Himalayas and continental rifts such as that in East Africa, which profoundly affect atmospheric circulation, creating deserts and monsoons. Over tens to hundreds of millions of years, plate movements gradually rearrange the continents, creating new oceans and destroying old ones, making and breaking land and sea connections, assembling and disassembling supercontinents, resulting in fundamental changes in heat transport by ocean currents. Finally, over the very long term—billions of years—climate reflects slow changes in solar luminosity as the planet heads towards a fiery Armageddon. All but two of these controls are direct or indirect consequences of plate tectonics.

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