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The Suburban Golf Course, Reconsidered For The Age Of Climate Change

The Suburban Golf Course, Reconsidered For The Age Of Climate Change

How a community of civic-minded Texans filed a lawsuit to halt real-estate development on a golf course, then took action to transform it into a 200-acre, flood-resistant conservancy.

[Photo: Stan Cook]

Less than four years ago, the golf course at the center of Clear Lake City, Texas, looked like any other suburban golf course, with vast tracts of meticulously manicured lawns stretched across 178 acres of rolling hills. Golf courses are one of the least sustainable uses of urban green space, and like any of the thousands of golf courses scattered throughout the U.S.—which make up a whopping 45% of golf courses worldwide—Clear Lake City’s required an inordinate amount of water for maintenance and upkeep. But today, the golf course is something else entirely: a glimpse at the future of climate change resilience.

With an ongoing, five-phase project called Exploration Green, Clear Lake City has begun to transform the former country club into a network of engineered, flood-detention ponds designed to accommodate an estimated half billion gallons of stormwater. Each of the ponds, which will undergo fine grading and erosion control, will act as giant, slow-draining landing basins to harness water and mitigate flooding to immediate areas. 

The new systems will greatly expand upon the city’s preexisting drainage ditches, which have long proved insufficient for the town’s explosion of development and growth in recent decades, and overwhelmed communities downstream during heavy rainfalls. Working to accommodate water rather than blockade it, Clear Lake City’s residents are embracing a strategy of learning to live with nature—a tactic that the Dutch have been known to practice to great success. When completed, the Clear Lake City Water Authority (CLCWA) will have essentially retrofitted the city’s existing landscape to withstand a 100-year storm event.

[Image: SWA]

A PRESSING NEED

Last August, Hurricane Harvey swept through the region, dropping upwards of 60 inches of rainfall and causing an estimated $125 billion of damage. It was the second most destructive hurricane in the U.S. on record, after Katrina. Luckily for the citizens of Clear Lake City, Phase 1 of Exploration Green was nearing completion—and saved nearly 200 homes that would have otherwise flooded. After witnessing its success, the CLCWA took steps to aggressively fast-track its initial 15-year project timeline to just five years, with one 100,000-acre detention pond to be completed per year. When all five phases of Exploration Green are completed in 2022, the revamped green space is projected to protect more than 2,000 flood-prone homes from heavy rains and stormwater runoff.

Climate change is here. Cities need to adapt—and faster than they realize, with lean solutions that, like Exploration Green, make use of existing infrastructure. Here’s what Clear Lake City is doing to make resiliency a reality—and what other flood-prone cities could learn.

[Photo: Jerry Hamby]

A GRASSROOTS EFFORT

The long saga of reclaiming the golf course began in 2005, when its owner, Renaissance Golf Group LLC, looked to sell the land to residential and commercial developers for a hefty profit. Shuttered for nearly a decade after losing popularity over the years, the golf course had already become a de facto park for local residents.

Wary of recent overdevelopment and increasing flood risk in the community, the city’s residents approached the CLCWA to see what could be done. The water authority, in turn, hired two hydrologists to survey the property “to see how potential development would affect flooding,” says board president John Branch. After determining that paving the green space would significantly increase flooding, Branch, the water authority, and a team of community members began a battle to acquire the land and halt further development.

When the owners denied the CLCWA’s offer to purchase the golf course, they had the land publicly condemned and took it to court, in a case that motioned through the local court system, and up to the appellate circuit. “An appeal would have gone up to the State Supreme Court,” says Branch, “at which point the seller decided he’d rather cut his losses and go ahead and sell it to us.”

In 2011, the CLCWA successfully acquired the land for $6.2 million—significantly below its real estate appraisal that reached as high as $15 million. Through a series of Town Hall meetings that followed, the idea for Exploration Green was born. The water authority hired Houston-based landscape architecture and urban design firm SWA Group—which has worked on local projects including Buffalo Bayou and Hermann Park—to create a master plan for a newly converted green space encompassing permanent water storage, as well as wetlands, and native habitats that will serve as a year-round park for residents. 

As Branch attests, forming the idea for Exploration Green and getting it off the ground would not have been possible without enthusiastic involvement from the community—many whom are longtime employees, colleagues, and contractors of the nearby NASA Johnson Space Center (which opened in 1973), and the various aerospace engineering, biochemical, and petrochemical industries also stationed in proximity. “I’m a former Shell employee and can bring in some engineering tech knowledge from a different industry,” says Branch, “but most everyone else on the board are NASA employees or contractors.” 

While not all residents have rallied behind the effort (a small number of them convened in 2013 to form the organization Friends of the Old Golf Course, in opposition), it has largely been supported by a majority consensus through the Town Hall meetings. Exploration Green, Branch explains, is named to nod to the community’s collective ties to pioneering science efforts, as well as to Houston’s urban park, Discovery Green.

[Photo: Jerry Hamby]

AN ENGINEERED LANDSCAPE

When Clear Lake City—a master-planned, residential community on the south-eastern edge of Houston, and the first of its kind to be built in Texas—was first developed in 1963, its design placed a golf course at the center of the community. Five decades on, the centralized green space, which snakes throughout the community, has proved to be a unique boon to Exploration Green. Crucially, because the community was also developed before there were any existing water, sewage, or drainage facilities in place, Clear Lake City—and its water systems, administered under CLCWA—holds infrastructural autonomy from the city of Houston.

This proved beneficial for the CLCWA, which was able to more nimbly begin construction efforts, notes Kelly Shipley, an associate project manager of Lockwood, Andrews, & Newnam Inc., the firm that is design engineering the project and overseeing construction. “The area was built before detention requirements existed, so there was nothing there,” says Branch. “But because [the golf course] was open green space,” she adds, “it had absorbed a lot of the rainwater,” making it an ideal site for detention ponds.

“The goal of Harris County’s Flood Control is to get water off the streets and out of the area—so their existing drainage channels are made to do that,” Shipley explains. “What Clear Lake is doing is converting those channels into city detention ponds, which, instead of turning the water out, will slow it down, and allow more time for the water to get back out into the bayous and the Gulf. It’s retaining water, and providing a place for that water to go and prevent it from flooding people downstream.”

Engineering each of the detention ponds will require a huge excavation effort, and the team estimates the removal of more than 200,000 dump trucks of soil over the course of the project, a logistical demand that played a large factor in determining feasibility for an expedited completion schedule. The nearly 340,00 cubic yards of soil that have been excavated thus far for Phase 1, Branch said, has been sold to a nearby development to use as fill.

[Photo: Jerry Hamby]

MORE THAN A SEASONAL SOLUTION, A YEAR-ROUND AMENITY

The strategy of building to accommodate storm runoff, rather than blockade or banish it, is core to Exploration Green—and as part of that, the community has also taken steps to ensure the place can double as a park for the vast majority of the year when it’s not storm season.

“We kind of looked around and said, ‘Hey, we don’t want it to just be a big hole in the ground with a fence around,’” says Branch. “We wanted it to be something special and kind of the same flavor of a green open space that could be used by the community.”

To that point, each of the detention ponds will maintain an amount of water year-round to create the feeling of a natural lake, surrounded by six miles of recreational hiking and bicycling trails. While the CLCWA will continue to administer the construction and maintenance of Exploration Green, the Explorer Green Conservancy—a non-profit entity formed by residents and volunteers—will spearhead fundraising and restoration efforts to bring native wildlife, wetland grasses, and trees to the site. Aside from beautifying the space for day-to-day use, the plantings will also help naturally treat contaminated stormwater before it’s released into the drainage systems and bayous.

Alliances and partnerships with other organizations have followed. Trees for Houston is donating 1,000 young trees for each phase of the project, and the Texas Coastal Watershed Program have provided a grant that will be used to create a wetlands nursery. “We’re also working with the Houston-Galveston Area Council to connect our hike and bike trails to existing trails throughout the county,” Branch says.

[Image: Lecon, Inc.]

A CASE FOR HOUSTON’S GOLF COURSES

Hurricane Harvey was an important test, and Phase 1 of Exploration Green passed–even as it was under construction.

That empowered the CLCWA to open-source its design on the Exploration Green website, with the hopes that others would be able to benefit from their research. Other flood-prone communities in the Greater Houston region, including Inwood Forest, which was hard hit by Harvey, have already reached out to learn from their model, says Branch, as have various communities from other regions of the country, including Michigan and Virginia.

In a recent study conducted by the University of Houston’s Hobby School of Public Affairs, a majority of more than 2,000 residents polled primarily from Harris County voiced support for tighter building code restrictions and increased infrastructure projects to control flooding. Yet that same group also voiced significant opposition to funding those building measures through a tax hike—emphasizing a problematic divide between reaching a popular consensus, and having the means and agency to address it.

As Branch points out, many of Houston’s golf courses were flooded when Harvey hit the region last August—making Exploration Green an especially relevant case study. While a unique set of advantageous circumstances enabled the residents of Clear Lake City to take direct action on a swift timeline, he believes communities everywhere should feel empowered to engage and bring about direct change in their hometowns.

“We were a government entity, the people here supported us, they wanted something done, and there are a lot of ways to build it,” he added. “But you just can’t sit around waiting for someone else to do something.”

 

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Local infrastructure can encourage healthy decisions

Audrey Power, of Topeka, says she walks on the Shunga Trail every day for her health. (Thad Allton/The Capital-Journal)

The environment people live in has a big influence on how healthy they are.

 

That doesn’t mean failed New Year’s resolutions can be blamed entirely on surroundings — a healthy lifestyle is still largely determined by individual choices — but infrastructure and community initiatives can go a long way in encouraging residents to make healthier, more responsible decisions.

Shawnee County is on the path to making this a reality for its residents, thanks to a variety of planned additions to trails and walkways.

“Our 10-year master plan is to have 150 miles of trails in the county,” said Mike McLaughlin, communications and public information supervisor for Shawnee County Parks and Recreation. “We currently have just over 54 miles. An important element of the trails is connectivity. If we can get the current trails to connect to one another, it encourages more use, and people can use them to get to more places for more reasons.”

The Kansas Department of Transportation recently provided a grant to extend the Deer Creek Trail from S.E. 10th Street through Dornwood Park to S.E. 25th Street. McLaughlin said the hope is to eventually connect it to the Lake Shawnee Trail. That would allow cyclists, or ambitious runners, the ability to start on Shunga Trail at its new S.W. 29th and McClure entry point and travel all the way from southwest Topeka to Lake Shawnee without leaving the trail.

McLaughlin said the deciding factor between whether someone hops in a car or walks or bikes to their destination often comes down to how close a trail is to their residence. That’s just one example of how improved accessibility can enhance a community’s health.

“The best policies are those that make the healthy choice the easy one. That’s not always the case,” said Gianfranco Pezzino, senior fellow and team leader for public health systems and services at the Kansas Health Institute. “If you live, for example, in a place that doesn’t have easy access to affordable fresh food, the easy choice is to go to a convenience store around the corner to buy food less healthy for you.”

For that reason, Pezzino said, the 2016 closure of Dillons at S.W. Huntoon St. and Washburn Ave. is a sore spot for him. While driving an extra two to three miles to another Dillons store may not seem like a burden to some, those without cars are more likely to choose unhealthy options without a grocery store within walking distance.

The issues, though, are challenging. Dan Partridge, director of the Lawrence-Douglas County Health Department, said the Lawrence community has been working on the food desert issue for years, looking particularly at East and North Lawrence areas that don’t have adequate access to food.

“It’s been a long road,” he said. “It’s really about a grocer has to turn a profit. It’s hard to overcome that when the market analysis doesn’t look promising.”

Researchers like Pezzino at the KHI conduct studies that lead to publications created for policymakers, arming them with analysis of the community so they can make informed decisions that affect the health of Kansans.

A 2017 survey by the National Recreation and Park Association showed 85 percent of Americans seek high-quality parks and recreation amenities when choosing a place to live, and 95 percent believe it’s important for their local agency to protect the environment by acquiring and maintaining parks and trails.

“If people live in neighborhoods that have damaged sidewalks or not enough lights, or aren’t near pleasant parks or walkways, they won’t do it,” Pezzino said. “If they don’t have the transportation, they can’t go to places like Lake Shawnee or Gage Park.”

While the thought of trails passing by every neighborhood is nice, reaching the 150-mile total envisioned in the county’s master plan takes funding. McLaughlin said the community’s private companies have helped in that regard.

Blue Cross Blue Shield of Kansas made contributions to fund a fitness loop trail at the Shawnee North Community Center. The health insurance company sees obvious benefits from encouraging physical activity among residents and regularly awards funding to health initiatives in its 103-county service area.

BCBS partners with the Kansas Association for Youth in a “Be the Spark” program that provides grants creating the opportunity for middle school and high school students to be physically active. Another initiative, Pathways to a Healthy Kansas, promotes physical activity, nutrition and tobacco-free environments for 16 communities across the state.

“In my opinion, it makes sense for the industry we’re in to improve the health of the community,” said Marlou Wegener, chief operating officer of the BCBS of Kansas Foundation. “It’s a goal for us to place a strong emphasis on supporting the communities we serve.”

Azura Credit Union made a $180,000 gift for naming rights, trail markers and maps for Azura Trails at Skyline Park. McLaughlin said the 4.7 miles of trails, which cover Burnett’s Mound, wooded areas and prairies, offer the most panoramic views in Shawnee County. Before the signs were installed, most people didn’t even know the trails were there.

If the nearly 100 miles of additions are completed as planned over the next decade, the trails — and the opportunity for a healthier means of transportation — will be hard to miss.

“When thinking about changing behaviors, you need to be physically able to do it, of course, but you also need the opportunity and the motivation to make the change,” Pezzino said. “We need to make sure people have the opportunity to begin with. That alone might not be enough, but without the opportunity, people won’t have what they need to develop healthier behaviors.”

Reporter Morgan Chilson contributed to this story.

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Maximizing Benefits of Trees in Hot Climates

http://www.thebrittonfund.org/wp-content/uploads/2012/06/BFhotclimates2013.pdf

Everyone appreciates cool shade on a hot day. But in urban settings in the arid west, trees provide benefits beyond
the shade they cast. Researchers at the Center for Urban Forest Research in Davis, CA, have been working since
1992 to quantify the benefits that trees provide. However, with water supplies dwindling as population grows, arbor‐
ists must help educate the general public on how to maximize these benefits while conserving resources.
Trees provide a multitude of benefits. During hot months, the obvious benefit is savings on air conditioning,
usually powered by electricity. Saving money on power bills will be the most apparent advantage that can be “sold” to
residential and commercial clients, as well as to municipalities that are implementing tree care budgets.
There are other less obvious yet quantifiable benefits. Mature trees increase property values. Not only do they
increase “curb appeal,” research shows that residential properties with trees fetch a higher selling price than those
without. The HomeGain.com 2012 National Home Improvement Survey stated that landscape improvements provide a
whopping 215 percent return on investment when selling a home.
BENEFITS BEYOND AESTHETICS
Through photosynthesis, trees use carbon dioxide and produce
oxygen. Climate change has increased concern for reducing carbon
“footprints.” Trees absorb carbon and sequester it in their the leaves,
branches, trunks and roots while alive. This storage continues with
wood in service as buildings and furniture. Trees also facilitate the
storage of carbon in soils by fueling the growth of mycorrhizae on their
roots.
Air quality is improved by the trees that are planted and prop‐
erly maintained. Trees absorb pollutants such as ozone and “grab”
drifting smoke, dust and other particulate matter.
Finally, trees intercept storm water and turn it into a resource
instead of a liability. Storm water may contain a cocktail of pollutants
such as gasoline, pesticides and fertilizer nutrients that end up in
oceans, rivers and wetlands. Trees divert torrential rains with their leaves and their roots absorb water, holding the soil
and slowing erosion.
RUNNING THE NUMBERS
Tree benefits are often calculated using “Leaf Surface Area” (LSA). The greater the LSA, the greater the bene‐
fits. What this amounts to is the bigger the tree, the bigger the benefits. Along the same lines, the longer the tree
grows and thrives, the bigger the payback.
While calculating LSA can be a complex procedure, there are many resources available to determine a tree’s
value. For example, the National Tree Benefit Calculator allows a user to input a zip code, then a tree’s species and size
to calculate an overall benefit in dollars, as well as storm water retention, increase in property value, energy savings,
air quality benefits and atmospheric carbon capture, all monetized. Using the calculator, a five‐inch diameter yellow
palo verde tree in the Las Vegas area provides $44 in benefits a year. The benefit more than doubles to $103 if the tree
grows to 10 inches in diameter.
LOCATION, LOCATION, LOCATION
Maximizing these benefits requires proper tree selection, placement, planting and maintenance. Sources for
species selection include the Cooperative Extension, numerous books available from any major bookseller and even the
local water authority.
To reap the greatest energy savings in hot climates, trees should be planted on the east and west sides of a
building, to provide shade to the west or southwest exterior windows. Trees should be planted so the mature canopy
edge is as close to the building as possible to maximize summer cooling, although access and fire safety must be con‐
sidered. Deciduous trees allow the sun to provide winter heating, thus reducing winter fuel use and cost.
Maximizing Benefits of Trees in Hot Climates
The shade that trees provide in hot climates go beyond
aesthetics and can be quantified. All photos courtesy:
Helen M. Stone
www.thebrittonfund.org
For optimal carbon capture, grouping plants with similar needs will make irrigation and other maintenance
procedures more efficient, which will reduce carbon inputs. Woody plants such as trees and shrubs sequester more
carbon than grasses and other herbaceous plants.  
Trees in mulched areas are better carbon collectors than trees in turfgrass. While fast‐growing trees sequester
more carbon early in their lives, they usually have a shorter lifespan than slow‐growing trees, so plant a diversity of
species for the best long‐tem results.
For improving air quality, trees planted near streets and park‐
ing lots collect dust and other particulate matter. Not only do they in‐
tercept and remove pollutants, their mitigating qualities also reduce
gases and hydrocarbons emitted by parked cars as the engines cool
down.
SIZE MATTERS
Although large trees provide more cooling than small ones, be
sure the tree has room to grow. A massive oak in a four‐by‐four foot
cutout in a parking lot will only struggle and succumb, while an acacia
can adapt to the small space and provide cooling for years. Parking lots
can be designed so that trees have adequate soil volume to establish a
large, healthy root system.
Minimize pruning by adopting structural pruning practices that
build a strong tree architecture. Avoid thinning trees, as this reduces
their effectiveness as cooling and shading features in the landscape. Prune in the dormant season when leave area re‐
duction is less important to energy saving requirements of the warmer months.
WATER ISSUES
When storm water interception is a concern, look for trees that have big, rough leaves or dense thick cano‐
pies such as conifers. Conifers are also a good choice when choosing “air cleaners” because they provide shade and
foliage all year. Trees with long leaf stems such as maple or ash and rough or fuzzy leaves (i.e. sycamore and oak) are
especially efficient at scrubbing air pollutants.
Water is a major issue in arid climates, and the benefits that trees provide must offset the water they need to
thrive. Choosing desert species such as mesquite, acacia and palo verde is recommended, as well as low‐water‐use spe‐
cies from Mediterranean climates with little summer rainfall.
According to the Arizona Municipal Water Authority (AMWA), a mature desert tree will use 4,000 gallons of
water a year. Obviously, trees use more water in summer than winter, so irrigation systems must be designed to ac‐
commodate mature trees at peak usage. However, proper scheduling is crucial. Schedules must be adjusted so that
irrigation is decreased (or even eliminated), during rainy winter months. Mulch also conserves soil moisture.
A wise native plant restoration specialist once said that people don’t live in deserts — they live in oases. Trees
provide incomparable benefits to the health and well being of desert dwellers, but proper selection, design, planting
and maintenance are critical to make the advantages outweigh the inputs they require.
Further Reading/Links:  
Tree Benefit Calculator
http://www.treebenefits.com/calculator/index.cfm
Desert Southwest Community Tree Guide
http://www.fs.fed.us/psw/programs/cufr/products/cufr542_72dpiDsrtSWCommTreeGd04.pdf
Potential of Tree Shade for Reducing Residential Energy Use in California
http://joa.isa‐arbor.com/request.asp?JournalID=1&ArticleID=2704&Type=2
Fourth in a series of 10 Technical Information sheets by Helen M. Stone and Dr. AJ Downer. Funded by The Britton
Fund, Inc. and supported by the Western Chapter of the International Society of Arboriculture. Copyright 2013.

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Here’s How Cities Can Get the Most out of Their Parks

Neighborhood green spaces aren’t always living up to their full potential.

A neighborhood park can be a powerful tool to help nearby residents lead healthier lives. According to one study, every dollar spent on creating and maintaining park trails saves nearly $3 in healthcare expenses. And America is chock full of neighborhood parks: Across the country, there are over 9,000 local parks and recreation departments and more than 100,000 public park facilities.

Parks seem like an ideal place for Americans to meet the national recommendations for physical activity (an hour a day for youth and a 150 minutes a week for adults). But because neighborhood parks are rarely designed with urban health in mind, these spaces—which the study defines as anywhere from two to 20 acres—often don’t fulfill their potential as pieces of public health infrastructure. A new study by researchers from the RAND Corporation, City Parks Alliance, and The Trust for Public Land is offering some solutions.

Researchers analyzed 175 neighborhood parks in 25 major Americancities. From 2014 to 2016 they observed park use, park-based physical activity, and park conditions, as well as the way users felt about their local parks. The study points to tangible ways that cities can encourage residents to use parks more in general, and for physical activity in particular. Among those recommendations: better facilities, targeted programing, and more marketing.

“The first thing a park needs is facilities and amenities,” says Deborah A. Cohen, a senior researcher at the RAND Corporation. “Parks used the least are ones that didn’t have anything in them. To make a playground more attractive to kids, it’s got to have lots of different features—it can’t just be swings. Kids like spinners, they also like water features. Make sure there’s something there in the park people can come and see.”

Park usage varies based on different factors such as age, gender, and socioeconomic status. Poorer communities are less likely to be frequent visitors: In the study, a 10 percentage point increase in local household poverty correlated with a 12 percent decrease in park use. Research also shows that most parks are geared toward youth rather than adults. Nearly all of the parks in the study had outdoor basketball courts and baseball fields, but only a third had a walking loop. When they were present, these loops were the amenity that generated the most activity for adults and seniors. Researchers found that park usage skewed male (57 percent) and young—seniors represented only 4 percent of park visitors. However, seniors make up 20 percent of the general U.S. population; a marked effort at engaging them would increase overall park usage and likely help to make the demographic healthier.

The report argues that parks should cater to the various demographics in the surrounding community. (Phil Noble/Reuters)

Targeted programming is key, says Catherine Nagle, the executive director of City Parks Alliance. Parks need to “provide professional staff to organize more programming locally that serves the needs of that particular neighborhood,” she says. Nagle observes that communities with young families sometimes want yoga classes for mothers and infants, while those with older or immigrant populations may have different needs. Additionally, supervised activities, such as dog training, increased average park use by 48 percent. Yet more than half of the parks surveyed had no supervised programming at all.

 
These activities draw residents in, Cohen says, because humans are social by nature. But you still need to get them to the park. “Facilities and amenities are important, but marketing is really important, because most people don’t know what’s available in their parks,” adds Cohen. Promotional materials would go a long way in bolstering park usage; materials like banners and signs advertising park activities led to more than 60 percent increase in both the number of park users and the number of hours those users exercised.

One of the largest barriers to building better park infrastructure and programs is budget. Out of the 119 park administrators surveyed in the study, half said their parks had gone through budget and staff decreases in the past two years. These budget shortfalls—and the ensuing decline in park hours and facilities—become a spiral.

Nagel believes there are ways to work around a lack of funding, largely by leveraging the resources of private companies, nonprofits, and other city agencies. She recommends that parks explore working with community health centers and hospitals to connect “physical spaces with health providers and insurance companies—the entities that are taking care of our health needs but not on the preventative sides.” Nagel cites the success of public-private partnerships like the one between the Los Angeles Parks and Recreation department and the nonprofit Los Angeles Parks Foundation. Working in tandem, the organizations have created neighborhood parks in underserved neighborhoods.

“Parks have an unrealized potential to improve everyone’s quality of life and longevity, and that’s been too neglected,” says Cohen. “We need to focus more on these wonderful community assets.”

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Climate Change Is Complex. We’ve Got Answers to Your Questions.

https://www.nytimes.com/interactive/2017/climate/what-is-climate-change.html

Part 1

What is happening?

 

1.Climate change? Global warming? What do we call it?

Both are accurate, but they mean different things.

You can think of global warming as one type of climate change. The broader term covers changes beyond warmer temperatures, such as shifting rainfall patterns.

President Trump has claimed that scientists stopped referring to global warming and started calling it climate change because “the weather has been so cold” in winter. But the claim is false. Scientists have used both terms for decades.

2.How much is the Earth heating up?

Two degrees is more significant than it sounds.

As of early 2017, the Earth had warmed by roughly 2 degrees Fahrenheit (more than 1 degree Celsius) since 1880, when records began at a global scale. The number may sound low, but as an average over the surface of an entire planet, it is actually high, which explains why much of the world’s land ice is starting to melt and the oceans are rising at an accelerating pace. If greenhouse gas emissions continue unchecked, scientists say, the global warming could ultimately exceed 8 degrees Fahrenheit, which would undermine the planet’s capacity to support a large human population.

3.What is the greenhouse effect, and
how does it cause global warming?

We’ve known about it for more than a century. Really.

In the 19th century, scientists discovered that certain gases in the air trap and slow down heat that would otherwise escape to space. Carbon dioxide is a major player; without any of it in the air, the Earth would be a frozen wasteland. The first prediction that the planet would warm as humans released more of the gas was made in 1896. The gas has increased 43 percent above the pre-industrial level so far, and the Earth has warmed by roughly the amount that scientists predicted it would.

To read the full article follow the link below:

https://www.nytimes.com/interactive/2017/climate/what-is-climate-change.html