Geoengineering's time has come -- or so a chorus is beginning to swell. Since so far we've failed to apply political or economic fixes to the unfolding global warming disaster, a technofix can look -- depending on where you sit -- like either a slam-dunk no-brainer or a regrettable last resort.

Geoengineering means deploying technology to roll back climate change now that we've missed the opportunity to avert it. Schemes come mostly in two flavors: carbon dioxide removal and solar radiation management. In the former, we try to suck carbon dioxide out of the atmosphere and get it back in the ground; or we shunt CO2 aside at the smokestack before it gets to the atmosphere, and bury or store it; or we promote algae blooms that absorb CO2 at the ocean surface and then die off and carry it to the ocean floor. In the latter, we try to deflect solar energy from the Earth by stirring up reflective sea mist or seeding clouds with sulfur particles or doing something else to sunscreen the planet.

In other words: Tamper with the climate even more to deal with the fallout from our climate-tampering! Sounds terribly Rube-Goldbergy -- and it is. (If you want more detail, try Grist's explainer on the subject.) These are large-scale undertakings with large-scale implications for largely opaque systems that we don't largely grasp.

Unfortunately, the slam-dunkness of geoengineering turns out to be illusory at best. We really don't know if any of these schemes can or would work. How much time, energy, and money should we put into finding out?

Things are going to get a lot warmer around here. And everywhere.

Even if the entire global economy woke up tomorrow morning, drank its coffee, and swore off fossil fuels, our future would still unfold at higher temperatures than our past. You can dream up wisecracking variations on "Hot enough for you?" and "Getting hot in here!" all day -- believe me, we have -- and that fact would just sit there, staring dejectedly at you and refusing to crack a smile.

Here at Grist we looked at the news, eyed the calendar, and decided that it's time to turn our gaze in the thermometer's direction. Our theme of the month for May is Hot and Bothered -- which is not just how we feel about what our carbon emissions are doing to the climate, but also, increasingly, how we're all going to feel about what the climate is doing to us.

Here's some of what we're working on this month:

• Not so hot? Not so fast
  Perhaps you've heard the statistic that's been going around suggesting that the planet has not, in fact, grown any hotter for 15 years? We'll untangle what's true in this claim, what's not, and why it's not a "get out of jail free" card for climate-change deniers. (Hint: It may well have to do with oceans.)

• Hot towns
  As summers just keep getting hotter, which American cities are the most screwed -- and which best placed to ride out the rougher weather?

• Wildfires
  Last year, they burned an area the size of Massachusetts and Connecticut combined. How much worse can they, will they get? And why do we keep making our homes in places likely to be threatened by them?

• Heat map
  All summer, our handy-dandy 50-state map will track wildfires, droughts, storms -- all U.S. disasters that are potentially related to rising temperatures. By autumn, we'll have a record of all the scars this season will have wrought on our landscape.

• Now you see it
  We're putting together a stunning gallery of before-and-after shots of those places where once, there were glaciers, and now, there aren't.

• Don't just sweat there -- do something??
  As warming trends continue, so does the rising chorus of can-do optimists who argue that we have the technical capacity -- and perhaps the moral obligation -- to geoengineer our way out of the climate mess. Can humankind somehow pull down the Earth's shades? Should it? Grist, along with Earth Island Journal, is hosting a live discussion on this question this Thursday in Berkeley, Calif., at 7 p.m. Join us for "Hack the Sky" if you're nearby!

These and other stories await you during Grist's Hot and Bothered theme for May. Got other ideas along these lines? Tell us below in the comments, or on Twitter or Facebook.

We know that paying attention to the news about climate and the environment is unlikely to leave you in a sunny mood. That's as it should be. But we also know that if you let the green news get you too blue, you'll never summon the spirit to do anything about it.

That's why we've decided to make Happiness our theme of the month here at Grist for April. (And apologies for the slightly late start, but, you know, we had to get our taxes out of the way first.)

Don't fret that we've gone feel-good soft; we're not trading in our critical edge for the warm-and-fuzzies just yet. But we think that there are plenty of compelling questions to explore where the fields of "happiness studies" and sustainability overlap -- at the intersection of Bliss and Green, if you will.

We started asking these questions a couple of years ago with David Roberts' groundbreaking essay "The medium chill," which described trading in relentless ambition for "satisficing" -- "stepping off the aspirational treadmill, forgoing some material opportunities and accepting some material constraints in exchange for more time to spend on relationships and experiences."

As part of our Happiness Month, Roberts will revisit this topic. (Although he protests that he's already said his piece on the matter, we know that once he dives in again we'll have to rip his digits from the keyboard to get him to move on.)

Climate change is a Big Problem. Moving our energy economy off fossil fuels is a Big Problem. Transforming our factory food system into something healthier? Remodeling our cities around sustainable models? Protecting our air and water? Big Problems, all.

Sometimes the sheer size of these problems can overwhelm us and leave us listless and passive. Which is one reason we've picked an offbeat theme for our coverage this month: Get Small -- Micro Solutions to Macro Problems.

Can we steer around big obstacles by thinking differently -- diminutively -- about them? Can we tackle big challenges by breaking them down into smaller ones? Do massive, planetary-scale dilemmas look different at eye height?

"Small is beautiful," sure -- that idea has a proud and venerable pedigree. But "small is strong"? "Small wins"? "Small saves the planet"? These are the ideas we're going to kick around.

For example: Did you know that there are entire species of animal that are adapting to climate change by getting smaller? We've got 'em here for you!

We'll look at what climate change looks like up really close -- at the level of dust, snowflakes, and molecules.

We'll explore -- from all sides -- the hypothesis that neighborhoods and local communities may be better positioned to cope with climate-driven change than nations and megalopolises.

We'll take a look at the indomitable online popularity of tiny abodes -- mini-apartments and nano-houses.

And we're planning a contest in which you can help us come up with a better name than "shrinkage" or "downsizing" (or even "rightsizing") for what happens when something gets smaller so it can be better.

We hope you'll stick around and get small with us. And do add your own ideas on this theme in the comments below -- but keep them, you know, brief.

We've made some changes on our Grist front page -- in the service of a simpler, clearer, more sprightly delivery of Grist's non-grumpy green news. We're moving to a single, unified list of all our posts -- Grist List items, Gristmill news posts, features, blog posts, columns.

Some of you have met these changes already, because we've been showing them, selectively, for a couple of weeks. We did something that, while increasingly the norm in the web industry, remains a little uncommon in the online journalism world: a live A/B test of our new homepage design versus the old one.

A/B testing is a kind of controlled experiment with concrete results. Thirty percent of you got the "new" Grist. The rest of you got the existing version of the site. And we looked at what happened.

What did we learn? First, judging from the absence of howls of consternation from our never shy readership, the change didn't cause many of you to blink an eye. Second, our metrics showed that the new design actually boosted click-throughs from the homepage to story pages by enough percentage points to make a significant difference.

Of course, if you're reading Grist on your phone, as we know more and more of you are doing, then this is how you've been seeing our stories for some time. The mobile theme for our site (what you see if you visit Grist on your phone's browser) shows all our posts in a single stream. We know this works well because, hey, we read on our phones, too.

We know, too, that the homepage itself is the point of entry for a diminishing fraction of visitors to Grist. More commonly, now, you arrive on wings of Twitter or thumbs of Facebook, alight on a story or two, and flutter off. Such readers -- and indeed all our visitors -- are still only a click away from the complete Grist List and Gristmill pages; topics like Climate and Energy, Food, and Cities; and regulars like David Roberts and Ask Umbra.

Nothing in the world of digital publishing stands still for very long. So don't be surprised if you keep noticing little things changing around here -- we're probably testing another new tweak. And of course let us know what you think: in comments below, here or anywhere, or via email. Thanks!

For 33 years the Population Institute has given out its Global Media Awards, and this year, I'm proud to say, Grist's Senior Editor Lisa Hymas has won one.

The institute honored "7 Billion, Unpacked," an explanation in comic book format of the planet's crossing the 7-billion population mark. It ran in Grist in October 2011.

Hymas collaborated with comics artist Thomas Pitilli to create the feature, which was part of our special series on "What to Expect When You're Expanding."

Congratulations to Hymas (and us as well, I guess). We love comics!

Also: That 7 billion number is already way out of date.

This thing we call "the sharing economy" -- the messy, fascinating world of networked goods exchange, freecycling, carsharing, and beyond -- is an unusual hybrid of normally warring sensibilities and belief systems.

It's got enough touchy-feely-huggy utopianism to turn the stomach of any self-respecting contemporary skeptic. But it's got enough market-economics pragmatism to raise the hackles of your typical leftie communitarian.

The sharing economy, in other words, cuts across our assumptions in intriguing ways. That's one reason we've picked this subject as our January theme here at Grist. Another is that the sharing-economy vision offers one imaginable route around that big pileup on the road just ahead of us, where an out-of-control growth economy is slamming into the physics of climate.

Why is there so much buzz and innovation around sharing right now? Part of it is the limping economy, of course -- the "real one," the one that's all what's mine is mine. Part of it is a growing awareness that mindless consumption is a big ingredient in the recipe for our sweating climate. And then there's technology.

The internet has always threatened/promised to remove comfortable middlemen and disrupt existing profit margins. The money newspapers lost on classified revenues when Craigslist came along was also money that ended up, fractionally, in all our pockets when we stopped having to pay cash to place our classifieds.

Rinse and repeat, industry by industry. You end up with a good number of happy Airbnb customers as well as a good number of unhappy hoteliers. Now the car-free population can connect with car owners whose vehicles are idle; they're mostly pretty happy, but the taxi folks are steaming.

How can we square the ethos of sharing with a go-go internet startup culture that typically has at least one eye on IPOs and acquisitions? Are sharing and capitalism really at loggerheads, and if so, what could a "sharing business" possibly mean? Anybody got something good to trade for a set of drill bits? (I only used them once!)

Many of us are excited about the benefits, environmental and otherwise, of an economy that's less hellbent on exploiting resources for profit and more mindful of ways to get fuller, fairer use out of the (mountains of) stuff we've already got. To get those benefits, we're going to have to grapple with some of these tougher questions around sharing. So over the next couple of weeks we'll dig into them here. (Susie Cagle's nifty illustrated explainer is a good place to start.) We'll also try to provide you with some helpful resources. In the spirit of this thing, we trust you'll step up and share some of yours, too.

Two months ago, Grist blogger Philip Bump took a look at a new study of global warming data, prepared a short post explaining the findings, and wrote this headline to summarize his interpretation of the numbers: "If you're 27 or younger, you've never experienced a colder-than-average month."

The National Oceanic and Atmospheric Administration had reported an alarming but unfathomable statistic -- that the previous month had been "the 332nd consecutive month with an above-average temperature" across the Earth's land and sea surfaces.

Bump translated it into terms that made more direct sense to those of us who don't do instant calculations in our heads as we read.

His choice reframing of this information took wing across the web, the press, and social media, landing everywhere from a column by The New York Times' Nicholas Kristof to Slate to a post at Treehugger.

It has now reached the status of "statistic you no longer need to cite a source for," which is how it appeared in a front-page story in yesterday's New York Times: "Nobody who is under 28 has lived through a month of global temperatures that fell below the 20th-century average, because the last such month was February 1985."

Of course, the moment a number reaches that status, it also becomes a target for would-be debunkers. Some folks, like this guy at Forbes, charged that the headline was misleading, because -- though the data for global average temperatures is quite clear -- members of the under-27 set have nonetheless experienced "colder than average months" if you look at local, rather than global, averages. This is a convenient but specious dodge; the NOAA data was worldwide, and so was our point. We're talking, after all, about the planet, not your neighborhood.

When you succeed in planting an idea in the collective online consciousness, it's only human to want credit. Attribution helps earn trust; links are a courtesy. In the newsroom, you'll frequently hear the wounded cry of the journalist who feels somehow ripped off by the competitor who fails to offer a hat-tip.

But in the bigger picture, really, who cares? Ideas can't be patented, nor should anyone try. We're glad to see Bump's conceptual craftsmanship propagate across the network, with or without a link to the original. Part of our mission here at Grist is to keep trying out new ways of talking about the climate crisis until we find ones that stick. This one left a mark.

UPDATE: A friend writes in to point me to this Joe Romm post from 2011, which features a very similar notion: "People under 35 have never seen normal global temperatures." Romm's post in turn is based on one by Robert Grumbine that digs deeper into the numbers: "If you're younger than 26, you have never seen a month where the global mean was as cold as the 161 year average." (Bump tells me he'd never seen these posts before composing his.)

All of which, I think, is further reason to put aside the whole "whose idea is it?" discussion, focus on the substance, and try to understand what was successful here so we can repeat it. There's nothing new under the sun, but meanwhile, it keeps getting hotter here.

We knew this one was coming, but now it's official: Lisa Jackson, President Obama's long-embattled administrator of the Environmental Protection Agency, is leaving her post.

Jackson served for four years as lead environmental regulator for the Obama administration, taking innumerable volleys of criticism from all directions. Serious environmentalists felt she caved too regularly to White House-driven compromises, allowing the climate to become a footnote and essential initiatives to be watered down. Meanwhile, the Tea Party right set her up as a job-killing bogeyperson and marshal of a "war on coal." (Green types only wished that war was real.)

As the first African American EPA administrator, Jackson brought a more inclusive approach to her environmental work -- moving both her agency and the national public far beyond old green stereotypes. The achievements of Jackson's tenure were real: major improvements in automobile emissions standards, important new controls on mercury in power-plant fumes, and the first-ever federal ruling that greenhouse gases should be classed as pollutants.

And yet no one who is conscious of the climate crisis can fail to see the last four years as, fundamentally, a failure where it most counts -- a critical, fleeting, now-missed chance to jam open a closing window of opportunity and alter our global-warming course. Early in Obama's first term, the White House and a then-Democratic Congress took one futile run at a watered-down cap-and-trade measure, then played dead on the issue. Obama barely mentioned the climate during his reelection campaign. Prospects for stronger action remain dim.

We did it! Or rather, you did it: Thanks to all of you amazing Grist readers who rose to our challenge, our December fund drive hit its goal.

In 10 days we raised 2,530 donations for a total of $78,251.

This gives us even more goose bumps than the James Bond music that played on our mental soundtracks as we created the fund drive's secret-agent-y theme.

Why? Because it means that you share our belief that the stories we cover matter, and the work we do deserves support.