Thanks to new funding, MagLab geochemist Jeremy Owens will learn more about ancient climate change, extinctions, oxygen levels, and new species to understand future climate impacts.
In an interview this week, Owens talked about how his $75,000 award will advance his research; what ancient isotopic x Isotopic are different forms of the same chemical element that have slightly different atomic weights due to varying numbers of neutrons in the atom's nucleus. signatures can tell us about the Earth's history and modern climate change; and how nearly failing out of college became the turning point that launched his career.
When did you find out about the Sloan Research Fellowship?
It actually was on January 27, which is my birthday. It was a really nice birthday gift. They sent a nice email, which was quite a shock as it came through. You end up reading it at least three or four times thinking, "I clearly have misread this." It comes with some funding for future research, so we can go after new questions.
What kind of research do you do?
I'm a metal isotope oceanographer and paleo oceanographer. I'm interested in how certain tools — specific isotopes — can tell us about past Earth and climate change, and in how we can bring these tools together to learn new information to provide a more in-depth, nuanced understanding of how climate has changed in Earth's history. We're interested in the timing of these changes — when they happen, especially compared to extinctions or explosion of new species. But also, how severe are these climate change events? Did the ocean not only experience a loss of oxygen, but also become incredibly toxic because it contained hydrogen sulfide that caused these extinctions?
To understand these nuances, you have to look at a variety of isotope tools, which we largely haven't done in our field because they are each difficult measurements. But we're getting to a point where we can do this.
What does your research process look like?
The amount of work from start to finish is broad. We have to go out in the field and collect the sample first. Depending on the time period and what type of rocks we're analyzing, that will take us all over the world. If it's relatively recent geologic history — the last 200 million years — we have ships that go out and drill the ocean floor and get sediments and rocks. If it's older, then we go collect rocks that are generally uplifted onto continents.
From there, we bring this back to the lab and cut the rocks. Then we'll powder it so it becomes a nice, smooth, homogenized powder. We take it into the lab and become more like lab rats — the geochemistry part. We dissolve the rock almost entirely, or we might extract out certain portions, filtering out different elements or minerals. Then comes the important part: purifying the sample for the specific element that we're interested in. We then take that and run it on one of the mass spectrometers at the MagLab to analyze the isotopes of those various elements. At bare minimum, if everything is working perfectly, it's about a year from start to finish, from collecting the samples to actually running them — but usually longer.
Can you give a specific example of something you've discovered?
The isotopes we're interested in are what we call "proxies," which tell us information about the environment that occurred at a certain period. These elements aren't direct recorders, per se, of oxygen in the oceans. But they have a chemical fingerprint that allows us to interpret changes in oxygen in the ocean.
For instance, a lot of the work I've done in the last five years at the MagLab has been on thallium and vanadium isotopes. The reason thallium is so powerful is that it responds to changes in manganese oxide burial — the burial of these precipitants out of the ocean. That's important because manganese is the first element that responds to changes in oxygen. So, if oxygen is present, manganese will bond to it and form these manganese oxides, which take thallium out of the ocean and have a different isotopic signature. And if there's no oxygen, that manganese oxide that was once buried will actually re-dissolve, and manganese will go back to the ocean and not affect the thallium isotope signature. Thallium allows us to fingerprint changes in manganese, which is indirectly (but our best record) related to the amount of oxygen in the ocean. That's how thallium works as a "proxy." And what we've found out here in these last few years, which has been groundbreaking, is that the thallium is changing earlier than any other isotope proxies in the geologic record. And much of this response coincides with the start of extinction events, which we previously could not fingerprint. We just knew that the extinctions happened, but didn't have a good record of ocean oxygenation.
What makes you excited about that discovery?
It's exciting to understand Earth's history. But, to be honest, it actually scares me a little bit, because this discovery suggests that the loss of oxygen in the oceans directly has an impact on extinction events. Currently we're losing a significant amount of oxygen in our oceans. In the last 50 years, there has been a lot of data that suggests that this is happening. If this continues, it could be the start of a broader extinction in the marine record. We know this is already somewhat occurring, but it could be much more significant and could lead to future climate scenarios that are not favorable for current marine life.
What will your Sloan Research Fellowship money enable you to do?
There are two topics I would like to focus on. One is having a better understanding of what typical background conditions are during periods without significant extinctions. We don't really know, because it's hard to get funding for times in our history when there's not significant climate or biological change. Hopefully, we can go into a few time periods and look at the background state to understand what is "normal."
The second thing we'd like to do is study various proxies, various isotopes, of one single sample or one time period to better illustrate what may be occurring in Earth's history. We haven't been able to do that to this point because it's expensive to analyze all these different elements at the same time.
Earth is a complicated system with many feedbacks. Each element fills in a portion of the picture, but no single element can tell us the entire picture. And that is the challenge — to be able to separate each one of their strengths and weaknesses to understand the story that each one is telling us.
What other elements do you want to look at?
Historically, the elements that have been done for this kind of work are molybdenum isotopes and uranium isotopes. Each element can tell us about different chemical reactions that occur following the depletion of oxygen.
How will learning about what took place hundreds of millions of years ago shed light on climate change today?
Climate change is due to simple chemical reaction. As we're burning fossil fuels, we consume ancient organic matter and oxygen, and it combines and makes carbon dioxide and water, which occurs in our combustion engines. That same chemical reaction we know is happening in ancient Earth when we have these climate changes. More and more work is showing that many of these changes were related to major volcanism. And it turns out that volcanic emissions have very similar reactions; some of them go right through coal and oil beds: They're actually burning up that organic matter and releasing carbon dioxide into the atmosphere. So, the chemical reactions are identical between ancient climate events and what's happening today, but these are very different events.
The timescales of these major volcanism events were much, much slower — they probably took half a million to a million years, in many cases. And obviously, what we're doing today is much quicker. The sequence of events from these ancient climate perturbations, or extinction events, can tell us at least what the progression of the environment will look like. That's our best window to understand future climate scenarios. It may not be a perfect analogue, by any stretch, but it's the best, or only, one we have. We can study the history and understand how these events transpired. And that might relate to what's going to happen, potentially, in our future.
We want to understand how the Earth responds to these climate events, what the feedback mechanisms are. The Earth is always changing, but those feedbacks to get it back to a state of pre-vulcanism were very slow. The Earth will be fine, but maybe without us, because these reaction rates are very slow.
Is there anything else you want to tell us?
When I was a college student, at the beginning I was a reasonable but not a great student. But then I had a quarter that was just awful. But that was actually the turning point in my academic life. I had five more quarters, and I decided that I was either going to do this or not. So I turned around. I was mostly on the Dean's List after that.
The point is, many people have really bad quarters or semesters throughout their undergrad history. It's more about what you do after that. That quarter totally killed my GPA. I thought, there is no way I'm going to grad school. But as it turns out, the person that nominated me for this Sloan Research Fellowship, Dr. Timothy Lyons, actually talked me into applying for grad school and took me as a grad student and eventually became my Ph.D. advisor and mentor.
That really changed my life. No matter where you are, you can really blossom if you put the time and effort into it, and find somebody who is willing to invest in you and mentor you. But it takes a lot of time and effort.
Story by Kristen Coyne
Jeremy Owens, a researcher in the National MagLab's Geochemistry group, got some good news on his birthday late last month: He was a recipient of a prestigious Sloan Research Fellowship, awarded yearly to 126 early-career scientists and scholars in recognition of their distinguished performance and potential in their fields.
Owens, an assistant professor in the Department of Earth, Ocean and Atmospheric Science at Florida State University, had to sit quietly on his hot news until today, when the awards were officially announced.
Last modified on 02 November 2022
Shukrani kwa ufadhili mpya, Jeremy Owens, mtaalamu wa kijiolojia wa MagLab, atajifunza zaidi juu ya mabadiliko ya hali ya hewa ya kale, kutoweka, viwango vya oksijeni, na spishi mpya ili kuelewa athari za hali ya hewa za baadaye. Owens alisema kuwa tuzo hiyo ya dola 75,000 itasaidia kuendeleza utafiti wake, na kwamba isotopu za kale ni aina tofauti za elementi moja ambayo ina uzito tofauti wa atomu kutokana na idadi tofauti ya neutroni katika nyuklia ya atomu. "Mfano wa ""mwisho wa miaka"" unaweza kutuambia juu ya historia ya Dunia na mabadiliko ya hali ya hewa ya kisasa; na jinsi karibu kushindwa kutoka chuo kikuu ikawa hatua ya kugeuka ambayo ilizindua kazi yake." Ni lini uligundua kuhusu Sloan Research Fellowship? Kwa kweli, siku hiyo ilikuwa Januari 27, siku ya kuzaliwa kwangu. Ilikuwa zawadi nzuri sana ya siku ya kuzaliwa. Nilipokea barua pepe nzuri, ambayo ilishangaza sana. "Mimi huendelea kusoma kwa mara tatu au nne na kufikiri, ""Ni wazi kwamba nimesoma vibaya.""" Pia, inakuja na fedha kwa ajili ya utafiti wa baadaye, hivyo tunaweza kwenda baada ya maswali mapya. Unafanya utafiti wa aina gani? Kwa mfano, kuna utafiti wa isotopu za chuma katika bahari ya Paleo. "Ninavutiwa na jinsi zana fulani - isotopu maalum - zinaweza kutuambia juu ya mabadiliko ya hali ya hewa ya zamani ya Dunia, na jinsi tunaweza kuleta zana hizi pamoja ili kujifunza habari mpya ili kutoa uelewa wa kina zaidi, wa nuance wa jinsi hali ya hewa imebadilika katika historia ya Dunia. """ Tunapendezwa na wakati wa mabadiliko haya <unk> wakati yanapotokea, haswa ikilinganishwa na kutoweka au mlipuko wa spishi mpya. Lakini pia, ni mbaya kadiri gani matukio haya ya mabadiliko ya hali ya hewa? Je, bahari haikupoteza oksijeni tu, lakini pia ikawa na sumu kubwa kwa sababu ilikuwa na hidrojeni sulfidi ambayo ilisababisha kutoweka kwa wanyama hao? Ili kuelewa mambo haya, ni lazima tuangalie vifaa mbalimbali vya isotopu, ambavyo hatujafanya katika uwanja wetu kwa sababu kila moja ni vipimo vigumu. Lakini tunafikia hatua ambapo tunaweza kufanya hivyo. Utaratibu wako wa utafiti unafanana na nini? Kiasi cha kazi kutoka mwanzo hadi mwisho ni kikubwa. Lazima tuende nje ya uwanja na kukusanya sampuli kwanza. Kulingana na aina ya mawe na aina ya mawe ya kuchunguza, inaweza kuwa na athari kubwa kwa mazingira. Katika historia ya kijiolojia ya hivi karibuni, miaka milioni 200 iliyopita, meli za kuagiza zilikuwa zikichimba chini ya bahari na kupata matope na miamba. Ikiwa ni ya zamani, basi tunaenda kukusanya miamba ambayo kwa ujumla huinuliwa kwenye mabara. Kutoka hapo, tunaleta hii nyuma kwa maabara na kukata miamba. Kisha, kuunganisha na poda, na kuunda homogenized unga. Sisi kuchukua ndani ya maabara na kuwa zaidi kama panya maabara <unk> sehemu geochemistry. Kwa hivyo, tunachunguza mwamba kwa kiasi kikubwa, na kwa njia ya kuchuja, tunaondoa madini na madini. Kisha inakuja sehemu muhimu: kusafisha sampuli kwa ajili ya kipengele maalum kwamba sisi ni nia ya. Kwa mfano, kwa mfano, unaweza kutumia spectrometer ya masafa ya MagLab, ambayo ni vifaa vya kuchanganua isotopu za vitu mbalimbali. Kwa kiwango cha chini, ikiwa kila kitu kinafanya kazi kikamilifu, ni karibu mwaka kutoka mwanzo hadi mwisho, kutoka kukusanya sampuli hadi kuendesha kweli <unk> lakini kwa kawaida zaidi. Je, unaweza kutoa mfano hususa wa jambo ulilogundua? Isotopu za kihistoria zinajulikana kama proxies, ambazo zinatoa habari kuhusu mazingira ya wakati fulani. Vitu hivi si vichekesho vya moja kwa moja, vya oksijeni katika bahari. Lakini zina alama ya kemikali ambayo huturuhusu kutafsiri mabadiliko ya oksijeni baharini. Kwa mfano, kazi nyingi ambazo nimefanya katika miaka mitano iliyopita katika MagLab zimekuwa juu ya thallium na vanadium isotopes. Sababu thallium ni nguvu sana ni kwamba inajibu mabadiliko katika manganese oksidi kuzikwa <unk> kuzikwa ya precipitatants hizi nje ya bahari. Hii ni muhimu kwa sababu manganese ni kiungo cha kwanza ambacho huitikia mabadiliko ya oksijeni. Kwa hiyo, ikiwa oksijeni iko, manganese itaunganisha na kuunda oksidi hizi za manganese, ambazo huchukua thallium nje ya bahari na kuwa na saini tofauti ya isotopu. Kama hakuna oksijeni, oksidi ya manganese ambayo ilikuwa imezikwa mara moja itasumbuliwa tena, na manganese itarudi baharini na haitaathiri saini ya isotopu ya thallium. Thallium inatuwezesha kuchunguza mabadiliko ya alama za vidole katika manganese, ambayo ni moja kwa moja (lakini rekodi yetu bora) inayohusiana na kiasi cha oksijeni katika bahari. Hivyo ndivyo thallium inavyofanya kazi kama "msaidizi". Katika miaka ya hivi karibuni, thallium imebadilika mapema kuliko isotopu nyingine yoyote. Na mengi ya majibu haya yanaambatana na mwanzo wa matukio ya kutoweka, ambayo hapo awali hatukuweza kuchapisha. """Hatujui kwamba kutoweka kwa wanyama kulikuwa kumetokea, lakini hatuna rekodi nzuri ya oksijeni ya bahari." Ni nini kinachokufanya uwe na msisimko kuhusu ugunduzi huo? Ni jambo lenye kusisimua kuelewa historia ya Dunia. Lakini, kwa uaminifu, kwa kweli inaniogopesha kidogo, kwa sababu ugunduzi huu unaonyesha kwamba upotezaji wa oksijeni katika bahari una athari moja kwa moja kwa matukio ya kutoweka. Kwa sasa tunapoteza kiasi kikubwa cha oksijeni katika bahari zetu. Katika miaka 50 iliyopita, kuna habari nyingi ambazo zinaonyesha kwamba hii ni kweli. Ikiwa hali hii itaendelea, inaweza kuwa mwanzo wa kutoweka kwa wanyama wengi baharini. "Tunajua hii tayari inatokea kwa kiasi fulani, lakini inaweza kuwa muhimu zaidi na inaweza kusababisha matukio ya hali ya hewa ya baadaye ambayo si mazuri kwa maisha ya sasa ya baharini. """ Pesa zako za Sloan Research Fellowship zitakuwezesha kufanya nini? Kuna mada mbili ningependa kuzingatia. Moja ni kuwa na uelewa bora wa nini hali ya kawaida ya nyuma ni wakati wa vipindi bila kutoweka muhimu. """Hatujui kwa kweli, kwa sababu ni vigumu kupata ufadhili kwa nyakati katika historia yetu wakati hakuna mabadiliko makubwa ya hali ya hewa au ya kibiolojia." Kwa matumaini, tunaweza kwenda katika vipindi vichache vya muda na kuangalia hali ya nyuma kuelewa nini ni "kawaida". "Kitu cha pili tunachotaka kufanya ni kuchunguza vipimo mbalimbali, isotopu mbalimbali, za sampuli moja au kipindi kimoja cha wakati ili kuonyesha vizuri kile kinachoweza kutokea katika historia ya Dunia.""" Hatujaweza kufanya hivyo kwa wakati huu kwa sababu ni ghali kuchambua vipengele hivi vyote tofauti kwa wakati mmoja. Dunia ni mfumo tata wenye majibu mengi. Kila sehemu hujaza sehemu fulani ya picha, lakini hakuna sehemu moja inayoweza kutufundisha picha nzima. Na hiyo ni changamoto <unk> kuwa na uwezo wa kutenganisha kila moja ya nguvu zao na udhaifu kuelewa hadithi kwamba kila mmoja ni kutuambia. Ni mambo gani mengine unayotaka kuchunguza? Kihistoria, elementi ambazo zimefanywa kwa ajili ya aina hii ya kazi ni isotopu za molybdenum na isotopu za uranium. Kila kiungo kinaweza kutufundisha juu ya athari tofauti za kemikali zinazotokea baada ya oksijeni kutoweka. Kujifunza kuhusu matukio ya miaka milioni mia moja iliyopita kutatuwezeshaje kuelewa mabadiliko ya hali ya hewa? Mabadiliko ya hali ya hewa husababishwa na mmenyuko rahisi wa kemikali. Wakati wa kuchoma mafuta ya makaa ya mawe, sisi hutumia vitu vya kale vya kikaboni na oksijeni, na huchanganya na kutengeneza kaboni dioksidi na maji, ambayo hutokea katika injini zetu za mwako. Mageuzi hayo ya kemikali yanatokea katika dunia ya kale wakati wa mabadiliko ya hali ya hewa. Kazi nyingi zaidi na zaidi zinaonyesha kwamba mabadiliko mengi hayo yalitokana na volkano kubwa. Vimeng'enyaji vya volkano huathiri sana mazingira ya ndani, na baadhi ya vimeng'enyaji vinaweza kuharibu madini ya makaa ya mawe na mafuta, na kutokeza kaboni dioksidi katika anga. Mageuzi ya kemikali ni sawa na yale ya hali ya hewa ya kale na yale ya leo, lakini ni tofauti sana. Vipimo vya muda vya matukio haya makubwa ya volkano vilikuwa polepole sana - labda vilichukua nusu milioni hadi milioni moja ya miaka, katika visa vingi. Na kwa wazi, kile tunachofanya leo ni cha haraka zaidi. Mfuatano wa matukio kutoka kwa machafuko haya ya hali ya hewa ya kale, au matukio ya kutoweka, yanaweza kutuambia angalau jinsi maendeleo ya mazingira yatakavyoonekana. Hiyo ni dirisha letu bora la kuelewa matukio ya hali ya hewa ya baadaye. Inaweza kuwa si analogi kamilifu, kwa muda mrefu, lakini ni bora, au tu, moja tuna. Tunaweza kujifunza historia na kuelewa jinsi matukio hayo yalivyotokea. Na hiyo inaweza kuhusiana na kile kitakachotokea, uwezekano, katika siku zetu zijazo. Tunataka kuelewa jinsi Dunia inavyokabiliana na matukio haya ya hali ya hewa, ni nini utaratibu wa kurudisha nyuma. Dunia inabadilika daima, lakini majibu hayo ya kurudisha hali ya kabla ya volkano yalikuwa ya polepole sana. Dunia itakuwa sawa, lakini labda bila sisi, kwa sababu viwango hivi vya athari ni polepole sana. Je, kuna jambo lingine unalotaka kutuambia? Nilipokuwa mwanafunzi wa chuo kikuu, mwanzoni nilikuwa mwanafunzi mwenye busara lakini si mwanafunzi mzuri. Lakini kisha nilikuwa na robo ambayo ilikuwa tu mbaya. Lakini hiyo ilikuwa hatua ya kugeuka katika maisha yangu ya kitaaluma. Nilikuwa na fedha tano za robo, na niliamua kwamba nitafanya hili au la. Kwa hiyo nikageuka. Nilikuwa hasa kwenye Orodha ya Dean baada ya hapo. Jambo ni, watu wengi kuwa na robo mbaya sana au semesters katika historia yao undergrad. Ni zaidi kuhusu nini kufanya baada ya hapo. robo hiyo kabisa kuuawa GPA yangu. Nilifikiri, hakuna njia nitakayoenda shule ya kuhitimu. "Lakini kama ilivyoonekana, mtu ambaye alinipendekeza kwa hii Sloan Research Fellowship, Dk Timothy Lyons, kweli aliniambia kuomba kwa shule ya kuhitimu na kunichukua kama mwanafunzi wa kuhitimu na hatimaye akawa mshauri wangu wa PhD na mshauri. """ Jambo hilo lilibadili maisha yangu kabisa. Haijalishi uko wapi, unaweza kustawi ikiwa utaweka wakati na juhudi katika hilo, na kupata mtu ambaye yuko tayari kuwekeza ndani yako na kukufundisha. Lakini hilo huchukua wakati na jitihada nyingi. Jeremy Owens, mtafiti katika kikundi cha Geochemistry cha National MagLab, alipokea habari nzuri siku ya kuzaliwa kwake mwishoni mwa mwezi uliopita: Alikuwa mpokeaji wa Sloan Research Fellowship, iliyotolewa kila mwaka kwa wanasayansi na wasomi 126 wa kazi ya mapema kwa kutambua utendaji wao wa kipekee na uwezo katika nyanja zao. Owens, profesa msaidizi katika Idara ya Sayansi ya Dunia, Bahari na Anga katika Chuo Kikuu cha Jimbo la Florida, alilazimika kukaa kimya juu ya habari zake moto hadi leo, wakati tuzo zilitangazwa rasmi. Marekebisho ya mwisho yalitolewa tarehe 2 Novemba, 2020.