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The document summarizes a report by NASA and NOAA on global temperatures in 2012. It finds that 2012 was the 10th warmest year globally since record keeping began in 1880 according to NASA, and the 9th warmest according to NOAA. All seasons and geographical regions across the globe experienced above-average temperatures for the year. The continental US also had its warmest year on record and experienced widespread drought, according to NOAA.

NOAA/NASA

2012 Global Temperatures

James E. Hansen Thomas R. Karl
Director, NASA’s Goddard Institute for Space Studies Director, NOAA’s National Climatic Data Center

January 15, 2013 1
January 15, 2013 NOAA/NASA 2012 Global Temperatures

2012 Annual Temperature
NASA NOAA

Anomaly (1951-80 base period): 0.53°C
Anomaly (20th Century average): 0.57°C

January 15, 2013 NOAA/NASA 2012 Global Temperatures
2

December 2011 – February 2012
NASA NOAA

Anomaly (1951-80 base period): 0.38°C
Anomaly (20th Century average): 0.41°C

January 15, 2013 NOAA/NASA 2012 Global Temperatures
3

March – May 2012
NASA NOAA

Anomaly (1951-80 base period): 0.56°C
Anomaly (20th Century average): 0.61°C

January 15, 2013 NOAA/NASA 2012 Global Temperatures
4

June – August 2012
NASA NOAA

Anomaly (1951-80 base period): 0.58°C
Anomaly (20th Century average): 0.64°C

January 15, 2013 NOAA/NASA 2012 Global Temperatures
5

September – November 2012
NASA NOAA

Anomaly (1951-80 base period): 0.62°C
Anomaly (20th Century average): 0.66°C

January 15, 2013 NOAA/NASA 2012 Global Temperatures
6

Northern Hemisphere Land Summer
Temperature Anomalies
NASA
All Stations

Limited Stations

January 15, 2013 NOAA/NASA 2012 Global Temperatures
7

Warmest Year on Record for the Continental U.S.
NOAA
• 3.25F above 20th Century average

2012: 55.32F
1998: 54.32F
2006: 54.30F
1934: 54.13F
1999: 53.93F

1903: 50.74F
1924: 50.63F
1912: 50.34F
1895: 50.54F
1917: 50.11F

January 15, 2013 NOAA/NASA 2012 Global Temperatures
8

U.S. Drought of 2012
NOAA
Illinois

From MODIS data. Karl et al, 2012 EOS
Courtesy of I. Becker-Reshef, E. Vermote, M. Claverie and C.
Justice, University of Maryland.

9
January 15, 2013 NOAA/NASA 2012 Global Temperatures
9

NOAA/NASA

Thank you

Questions?

James E. Hansen Thomas R. Karl
Director, NASA’s Goddard Institute for Space Studies Director, NOAA’s National Climatic Data Center

January 15, 2013 10
January 15, 2013 NOAA/NASA 2012 Global Temperatures

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We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and 30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1 . Our search finds no candidates at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to infer the properties of the evolving luminosity function without binning in redshift or luminosity that marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results, and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5 from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical models for evolution of the dark matter halo mass function.

Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...

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The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.

THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.

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The ambient solar wind that flls the heliosphere originates from multiple sources in the solar corona and is highly structured. It is often described as high-speed, relatively homogeneous, plasma streams from coronal holes and slow-speed, highly variable, streams whose source regions are under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify solar wind sources and understand what drives the complexity seen in the heliosphere. By combining magnetic feld modelling and spectroscopic techniques with high-resolution observations and measurements, we show that the solar wind variability detected in situ by Solar Orbiter in March 2022 is driven by spatio-temporal changes in the magnetic connectivity to multiple sources in the solar atmosphere. The magnetic feld footpoints connected to the spacecraft moved from the boundaries of a coronal hole to one active region (12961) and then across to another region (12957). This is refected in the in situ measurements, which show the transition from fast to highly Alfvénic then to slow solar wind that is disrupted by the arrival of a coronal mass ejection. Our results describe solar wind variability at 0.5 au but are applicable to near-Earth observatories.

Multi-source connectivity as the driver of solar wind variability in the heli...

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Recent discoveries of Earth-sized planets transiting nearby M dwarfs have made it possible to characterize the atmospheres of terrestrial planets via follow-up spectroscopic observations. However, the number of such planets receiving low insolation is still small, limiting our ability to understand the diversity of the atmospheric composition and climates of temperate terrestrial planets. We report the discovery of an Earth-sized planet transiting the nearby (12 pc) inactive M3.0 dwarf Gliese 12 (TOI-6251) with an orbital period (Porb) of 12.76 days. The planet, Gliese 12 b, was initially identified as a candidate with an ambiguous Porb from TESS data. We confirmed the transit signal and Porb using ground-based photometry with MuSCAT2 and MuSCAT3, and validated the planetary nature of the signal using high-resolution images from Gemini/NIRI and Keck/NIRC2 as well as radial velocity (RV) measurements from the InfraRed Doppler instrument on the Subaru 8.2 m telescope and from CARMENES on the CAHA 3.5 m telescope. X-ray observations with XMM-Newton showed the host star is inactive, with an X-ray-to-bolometric luminosity ratio of log 5.7 L L X bol » - . Joint analysis of the light curves and RV measurements revealed that Gliese 12 b has a radius of 0.96 ± 0.05 R⊕,a3σ mass upper limit of 3.9 M⊕, and an equilibrium temperature of 315 ± 6 K assuming zero albedo. The transmission spectroscopy metric (TSM) value of Gliese 12 b is close to the TSM values of the TRAPPIST-1 planets, adding Gliese 12 b to the small list of potentially terrestrial, temperate planets amenable to atmospheric characterization with JWST.

Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Tr...

Sérgio Sacani

We report on the discovery of Gliese 12 b, the nearest transiting temperate, Earth-sized planet found to date. Gliese 12 is a bright (V = 12.6 mag, K = 7.8 mag) metal-poor M4V star only 12.162 ± 0.005 pc away from the Solar system with one of the lowest stellar activity levels known for M-dwarfs. A planet candidate was detected by TESS based on only 3 transits in sectors 42, 43, and 57, with an ambiguity in the orbital period due to observational gaps. We performed follow-up transit observations with CHEOPS and ground-based photometry with MINERVA-Australis, SPECULOOS, and Purple Mountain Observatory, as well as further TESS observations in sector 70. We statistically validate Gliese 12 b as a planet with an orbital period of 12.76144 ± 0.00006 d and a radius of 1.0 ± 0.1 R⊕, resulting in an equilibrium temperature of ∼315 K. Gliese 12 b has excellent future prospects for precise mass measurement, which may inform how planetary internal structure is affected by the stellar compositional environment. Gliese 12 b also represents one of the best targets to study whether Earth-like planets orbiting cool stars can retain their atmospheres, a crucial step to advance our understanding of habitability on Earth and across the galaxy.

Gliese 12 b, a temperate Earth-sized planet at 12 parsecs discovered with TES...

Sérgio Sacani

Within the uncertainties of involved astronomical and biological parameters, the Drake Equation typically predicts that there should be many exoplanets in our galaxy hosting active, communicative civilizations (ACCs). These optimistic calculations are however not supported by evidence, which is often referred to as the Fermi Paradox. Here, we elaborate on this long-standing enigma by showing the importance of planetary tectonic style for biological evolution. We summarize growing evidence that a prolonged transition from Mesoproterozoic active single lid tectonics (1.6 to 1.0 Ga) to modern plate tectonics occurred in the Neoproterozoic Era (1.0 to 0.541 Ga), which dramatically accelerated emergence and evolution of complex species. We further suggest that both continents and oceans are required for ACCs because early evolution of simple life must happen in water but late evolution of advanced life capable of creating technology must happen on land. We resolve the Fermi Paradox (1) by adding two additional terms to the Drake Equation: foc (the fraction of habitable exoplanets with significant continents and oceans) and fpt (the fraction of habitable exoplanets with significant continents and oceans that have had plate tectonics operating for at least 0.5 Ga); and (2) by demonstrating that the product of foc and fpt is very small (< 0.00003–0.002). We propose that the lack of evidence for ACCs reflects the scarcity of long-lived plate tectonics and/or continents and oceans on exoplanets with primitive life.

The importance of continents, oceans and plate tectonics for the evolution of...

Sérgio Sacani

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A Giant Impact Origin for the First Subduction on Earth

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Climate extremes likely to drive land mammal extinction during next supercont...

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Constraints on Neutrino Natal Kicks from Black-Hole Binary VFTS 243

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In this work, we assess the potential detectability of solar panels made of silicon on an Earth-like exoplanet as a potential technosignature. Silicon-based photovoltaic cells have high reflectance in the UV-VIS and in the near-IR, within the wavelength range of a space-based flagship mission concept like the Habitable Worlds Observatory (HWO). Assuming that only solar energy is used to provide the 2022 human energy needs with a land cover of ∼ 2.4%, and projecting the future energy demand assuming various growth-rate scenarios, we assess the detectability with an 8 m HWO-like telescope. Assuming the most favorable viewing orientation, and focusing on the strong absorption edge in the ultraviolet-to-visible (0.34 − 0.52 µm), we find that several 100s of hours of observation time is needed to reach a SNR of 5 for an Earth-like planet around a Sun-like star at 10pc, even with a solar panel coverage of ∼ 23% land coverage of a future Earth. We discuss the necessity of concepts like Kardeshev Type I/II civilizations and Dyson spheres, which would aim to harness vast amounts of energy. Even with much larger populations than today, the total energy use of human civilization would be orders of magnitude below the threshold for causing direct thermal heating or reaching the scale of a Kardashev Type I civilization. Any extraterrrestrial civilization that likewise achieves sustainable population levels may also find a limit on its need to expand, which suggests that a galaxy-spanning civilization as imagined in the Fermi paradox may not exist.

Detectability of Solar Panels as a Technosignature

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Recent observations of galaxy clusters and groups with misalignments between their central AGN jets and X-ray cavities, or with multiple misaligned cavities, have raised concerns about the jet – bubble connection in cooling cores, and the processes responsible for jet realignment. To investigate the frequency and causes of such misalignments, we construct a sample of 16 cool core galaxy clusters and groups. Using VLBA radio data we measure the parsec-scale position angle of the jets, and compare it with the position angle of the X-ray cavities detected in Chandra data. Using the overall sample and selected subsets, we consistently find that there is a 30% – 38% chance to find a misalignment larger than ∆Ψ = 45◦ when observing a cluster/group with a detected jet and at least one cavity. We determine that projection may account for an apparently large ∆Ψ only in a fraction of objects (∼35%), and given that gas dynamical disturbances (as sloshing) are found in both aligned and misaligned systems, we exclude environmental perturbation as the main driver of cavity – jet misalignment. Moreover, we find that large misalignments (up to ∼ 90◦ ) are favored over smaller ones (45◦ ≤ ∆Ψ ≤ 70◦ ), and that the change in jet direction can occur on timescales between one and a few tens of Myr. We conclude that misalignments are more likely related to actual reorientation of the jet axis, and we discuss several engine-based mechanisms that may cause these dramatic changes.

Jet reorientation in central galaxies of clusters and groups: insights from V...

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The magnetic dynamo cycle of the Sun features a distinct pattern: a propagating region of sunspot emergence appears around 30° latitude and vanishes near the equator every 11 years (ref. 1). Moreover, longitudinal flows called torsional oscillations closely shadow sunspot migration, undoubtedly sharing a common cause2. Contrary to theories suggesting deep origins of these phenomena, helioseismology pinpoints low-latitude torsional oscillations to the outer 5–10% of the Sun, the near-surface shear layer3,4. Within this zone, inwardly increasing differential rotation coupled with a poloidal magnetic field strongly implicates the magneto-rotational instability5,6, prominent in accretion-disk theory and observed in laboratory experiments7. Together, these two facts prompt the general question: whether the solar dynamo is possibly a near-surface instability. Here we report strong affirmative evidence in stark contrast to traditional models8 focusing on the deeper tachocline. Simple analytic estimates show that the near-surface magneto-rotational instability better explains the spatiotemporal scales of the torsional oscillations and inferred subsurface magnetic field amplitudes9. State-of-the-art numerical simulations corroborate these estimates and reproduce hemispherical magnetic current helicity laws10. The dynamo resulting from a well-understood near-surface phenomenon improves prospects for accurate predictions of full magnetic cycles and space weather, affecting the electromagnetic infrastructure of Earth.

The solar dynamo begins near the surface

Sérgio Sacani

In the Nice model of solar system formation, Uranus and Neptune undergo an orbital upheaval, sweeping through a planetesimal disk. The region of the disk from which material is accreted by the ice giants during this phase of their evolution has not previously been identified. We perform direct N-body orbital simulations of the four giant planets to determine the amount and origin of solid accretion during this orbital upheaval. We find that the ice giants undergo an extreme bombardment event, with collision rates as much as ∼3 per hour assuming km-sized planetesimals, increasing the total planet mass by up to ∼0.35%. In all cases, the initially outermost ice giant experiences the largest total enhancement. We determine that for some plausible planetesimal properties, the resulting atmospheric enrichment could potentially produce sufficient latent heat to alter the planetary cooling timescale according to existing models. Our findings suggest that substantial accretion during this phase of planetary evolution may have been sufficient to impact the atmospheric composition and thermal evolution of the ice giants, motivating future work on the fate of deposited solid material.

Extensive Pollution of Uranus and Neptune’s Atmospheres by Upsweep of Icy Mat...

Sérgio Sacani

The highest priority recommendation of the Astro2020 Decadal Survey for space-based astronomy was the construction of an observatory capable of characterizing habitable worlds. In this paper series we explore the detectability of and interference from exomoons and exorings serendipitously observed with the proposed Habitable Worlds Observatory (HWO) as it seeks to characterize exoplanets, starting in this manuscript with Earth-Moon analog mutual events. Unlike transits, which only occur in systems viewed near edge-on, shadow (i.e., solar eclipse) and lunar eclipse mutual events occur in almost every star-planet-moon system. The cadence of these events can vary widely from ∼yearly to multiple events per day, as was the case in our younger Earth-Moon system. Leveraging previous space-based (EPOXI) lightcurves of a Moon transit and performance predictions from the LUVOIR-B concept, we derive the detectability of Moon analogs with HWO. We determine that Earth-Moon analogs are detectable with observation of ∼2-20 mutual events for systems within 10 pc, and larger moons should remain detectable out to 20 pc. We explore the extent to which exomoon mutual events can mimic planet features and weather. We find that HWO wavelength coverage in the near-IR, specifically in the 1.4 µm water band where large moons can outshine their host planet, will aid in differentiating exomoon signals from exoplanet variability. Finally, we predict that exomoons formed through collision processes akin to our Moon are more likely to be detected in younger systems, where shorter orbital periods and favorable geometry enhance the probability and frequency of mutual events.

Exomoons & Exorings with the Habitable Worlds Observatory I: On the Detection...

Sérgio Sacani

Mars is a particularly attractive candidate among known astronomical objects to potentially host life. Results from space exploration missions have provided insights into Martian geochemistry that indicate oxychlorine species, particularly perchlorate, are ubiquitous features of the Martian geochemical landscape. Perchlorate presents potential obstacles for known forms of life due to its toxicity. However, it can also provide potential benefits, such as producing brines by deliquescence, like those thought to exist on present-day Mars. Here we show perchlorate brines support folding and catalysis of functional RNAs, while inactivating representative protein enzymes. Additionally, we show perchlorate and other oxychlorine species enable ribozyme functions, including homeostasis-like regulatory behavior and ribozyme-catalyzed chlorination of organic molecules. We suggest nucleic acids are uniquely wellsuited to hypersaline Martian environments. Furthermore, Martian near- or subsurface oxychlorine brines, and brines found in potential lifeforms, could provide a unique niche for biomolecular evolution.

Emergent ribozyme behaviors in oxychlorine brines indicate a unique niche for...

Sérgio Sacani

The thermal continuum emission observed from accreting black holes across X-ray bands has the potential to be leveraged as a powerful probe of the mass and spin of the central black hole. The vast majority of existing ‘continuum fitting’ models neglect emission sourced at and within the innermost stable circular orbit (ISCO) of the black hole. Numerical simulations, however, find non-zero emission sourced from these regions. In this work, we extend existing techniques by including the emission sourced from within the plunging region, utilizing new analytical models that reproduce the properties of numerical accretion simulations. We show that in general the neglected intra-ISCO emission produces a hot-and-small quasi-blackbody component, but can also produce a weak power-law tail for more extreme parameter regions. A similar hot-and-small blackbody component has been added in by hand in an ad hoc manner to previous analyses of X-ray binary spectra. We show that the X-ray spectrum of MAXI J1820+070 in a soft-state outburst is extremely well described by a full Kerr black hole disc, while conventional models that neglect intra-ISCO emission are unable to reproduce the data. We believe this represents the first robust detection of intra-ISCO emission in the literature, and allows additional constraints to be placed on the MAXI J1820 + 070 black hole spin which must be low a• < 0.5 to allow a detectable intra-ISCO region. Emission from within the ISCO is the dominant emission component in the MAXI J1820 + 070 spectrum between 6 and 10 keV, highlighting the necessity of including this region. Our continuum fitting model is made publicly available.

Continuum emission from within the plunging region of black hole discs

Sérgio Sacani

Studying the escaping atmospheres of highly irradiated exoplanets is critical for understanding the physical mechanisms that shape the demographics of close-in planets. A number of planetary outflows have been observed as excess H/He absorption during/after transit. Such an outflow has been observed for WASP-69b by multiple groups that disagree on the geometry and velocity structure of the outflow. Here, we report the detection of this planet’s outflow using Keck/NIRSPEC for the first time. We observed the outflow 1.28 hr after egress until the target set, demonstrating the outflow extends at least 5.8 × 105 km or 7.5 Rp This detection is significantly longer than previous observations, which report an outflow extending ∼2.2 planet radii just 1 yr prior. The outflow is blueshifted by −23 km s−1 in the planetary rest frame. We estimate a current mass-loss rate of 1 M⊕ Gyr−1 . Our observations are most consistent with an outflow that is strongly sculpted by ram pressure from the stellar wind. However, potential variability in the outflow could be due to time-varying interactions with the stellar wind or differences in instrumental precision.

WASP-69b’s Escaping Envelope Is Confined to a Tail Extending at Least 7 Rp

Sérgio Sacani

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Manganese‐RichSandstonesasanIndicatorofAncientOxic LakeWaterConditionsinGale...

Sérgio Sacani

Using deep archival observations from the Chandra X-ray Observatory, we present an analysis of linear X-ray-emitting features located within the southern portion of the Galactic center chimney, and oriented orthogonal to the Galactic plane, centered at coordinates l = 0.08◦ , b = −1.42◦ . The surface brightness and hardness ratio patterns are suggestive of a cylindrical morphology which may have been produced by a plasma outflow channel extending from the Galactic center. Our fits of the feature’s spectra favor a complex two-component model consisting of thermal and recombining plasma components, possibly a sign of shock compression or heating of the interstellar medium by outflowing material. Assuming a recombining plasma scenario, we further estimate the cooling timescale of this plasma to be on the order of a few hundred to thousands of years, leading us to speculate that a sequence of accretion events onto the Galactic Black Hole may be a plausible quasi-continuous energy source to sustain the observed morphology

X-rays from a Central “Exhaust Vent” of the Galactic Center Chimney

Sérgio Sacani

Marine and terrestrial biogeochemical models are key components of the Earth System Models (ESMs) used toproject future environmental changes. However, their slow adjustment time also hinders effective use of ESMsbecause of the enormous computational resources required to integrate them to a pre-industrial equilibrium. Here,a solution to this "spin-up" problem based on "sequence acceleration", is shown to accelerate equilibration of state-of-the-art marine biogeochemical models by over an order of magnitude. The technique can be applied in a "blackbox" fashion to existing models. Even under the challenging spin-up protocols used for Intergovernmental Panelon Climate Change (IPCC) simulations, this algorithm is 5 times faster. Preliminary results suggest that terrestrialmodels can be similarly accelerated, enabling a quantification of major parametric uncertainties in ESMs, improvedestimates of metrics such as climate sensitivity, and higher model resolution than currently feasible.

Efficient spin-up of Earth System Models usingsequence acceleration

Sérgio Sacani

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