Christmas is a season of broadly heightened sensory awareness — light, sound, touch and scent all contribute to shaping our powerful emotional attraction to the holiday experience. Our nervous systems are under relentless attack from Thanksgiving to New Year's.

I remember one Christmas morning
A winter's light and a distant choir
And the peal of a bell and that Christmas tree smell
And their eyes full of tinsel and fire
(I Believe in Father Christmas, Greg Lake)

Things we see, hear, handle and sniff play a central role in making the Yuletide season unique among holidays. Our afferent nerve fibers are bombarded in such steady and concentrated doses as to overwhelm our receptors. No wonder the kids get jacked up.

Lights, decorations, tar-tinkers and carols playing everywhere you go. Santa's helpers ringing bells on all the street corners. Everywhere good cheer, patience, civility and courtly behavior borne of the Christmas spirit. Simultaneously drawing energy from and feeding energy into everything. Everything feels so good!

Looks good, too. Canopies of decorations arching across metropolitan avenues. A village Christmas tree topped with a shining star in the park. Wreaths on doors, sidewalks full of shoppers toting packages, ribbons and wrappings stuffed into bulky shopping bags for the trip home from the store. Presents to be first secretly hidden from sight and then ostentatiously arranged and shown off around the tree.

And what a tree! Bedecked with garlands, beads, lights and ornaments that have endured among the family's possessions sometimes for generations. Scrooge was right. We do keep Christmas past, present and future in our hearts. Every December it pours out, to be reabsorbed through our eyes, our ears, our fingertips and, yes, our noses.

Yes, smells good, too. The olfactories play no secondary role.

Your nose tells you Christmas is close in everything from the cold, crisp air in your nostrils as you pick your way to church or town through the snow drifts in the light of early morning (in the car? drive with the windows open) to the blast of sweetness, spice and fruity aromas from cookies and cakes and pies baking in the oven at home.

Throughout the holiday season, cloves, cinnamon, nutmeg, gingerbread and mandarin oranges comingle with peppermint and chocolates. We identify and record them before we even taste them.

For the adults there's the pleasing bouquet of bourbon-laced eggnog or perhaps brandy-infused sidecars (depending on how seriously you take your holiday drinking). We quaff them while entertaining the neighbors, sitting around listening to the our old Christmas recordss and CDs, or just resharing time-worn and treasured family holiday stories.

In the living room the balsam or pine incense of the Christmas tree shares the air with the smoke of the fire crackling in the hearth and the evergreen branches and pine cones gracing the mantle.

On Christmas Day the fruity sweetness of baked goods gives way to the savory aroma of the roasting turkey or prime rib, or both.

Even before the food arrives, the dining room table contributes a scent of lit bayberry and beeswax candles glowing on a table set with the good china and crystal.

As the winter light fades, the wait for dinner becomes nearly as intolerable as the children's anxious bedroom vigil the previous night waiting for the darkness to expire.

But suppose, for a moment, you don't live inside a Currier and Ives Christmas card? Or the neighborhood gatherings are potlucks or catered affairs? Or the tree is artificial and the fireplace electric?

Not to worry. This is why God invented Chemistry.

There's a multitude of modern-living techniques designed to make your house reek of Christmas even if you lack many of the traditional aromatic standbys. Some you can make, some you can find and some you can buy. The fact, is making your house smell like Christmas has become a big business.

of course, the most obvious fallback is candles. They work great but can quickly run into real money if you're going to burn them for twelve straight days.

How about a homemade stove-top potpourri that will perfume your house for days and cost you only for some groceries? And when you're done, you and your friends can drink it. Just add vodka. It doesn't even have to be expensive vodka.

CRANBERRY & CINNAMON STOVE TOP POTPOURRI

• 2 oranges, sliced
• 3 cinnamon sticks
• 1 cup cranberries
• 3 teaspoons ground clove
• 2 teaspoons nutmeg
• 2 sprigs rosemary

Place ingredients into pot and fill with water to about 1 inch below brim and simmer. Should work for about three days according to Rachel Schultz, who publishes the website "On Homemaking." She has other, more complex potpourri recipes (not all potable) you can check out at rachelshultz.com

There are also oil diffusers and burners and even aerosols, all promising a wide range of holiday-themed scents. According to Demeter F.I. Inc. a scent maker, "Snow" is among top-selling scents during the Christmas season, along with "Egg Nog."

Senior Fragrance Development Manager Deborah Betz of International Flavors & Fragrances Inc., in New York, says changing holiday-odor fashion is trending this year toward hybrids of food and traditional Christmas scents like pine-cone-plus-apple. She also says manufacturers are beginning to cater to foreign noses with different Christmas ideals. (Yet another pernicious example of diversity attacking cultural tradition.)

"A lot of people think the holidays should smell like booze," she confides. She cites a cranberry pear Bellini candle and another called bubbly champagne, with hints of citrus and red currant.

But what else kindles Christmas feelings like the smell of a fresh-cut Christmas tree? More than 80 percent of American households where Christmas is observed use artificial trees, so that's a problem right there.

A polyvinylchloride Christmas tree may be more eco-friendly (until you throw it out); still it does nothing for your seasonal olfactories. So does modern chemistry have a solution?

Yes and no.

The compounds that create that Christmas Tree Smell comprise a fairly complex cocktail. Pinene, composed of two different molecules that are mirror images of each other, belongs to a class of hydrocarbons called terpenes. All trees release terpenes, but conifers particularly so. β-pinene has a fresh, woody fragrance, while α-pinene smells a bit more like turpentine. Both molecules are volatile liquids at room temperature, releasing most of the characteristic Christmas tree smell your nose recognizes.

Both pines and fir trees are rich in bornyl acetate, which produces a rich odor often described as balsamic or camphorous. Balsam firs and silver pines are two types of fragrant species rich in this compound.

Many conifers used for Christmas trees also waft odors from limonene (a citrus scent), myrcene (a terpene partly responsible for the aroma of hops, thyme, and cannabis), camphene (a camphor smell), and α-phellandrene (peppermint and citrus-smelling monoterpene). This courtesy of about.com: Why Christmas Trees Smell So Good

All by way of saying Christmas trees are a lot like Chekov's unhappy families. People's childhood reminiscences vary because different types of trees all have slightly different smells. So even with a natural tree you might be smelling someone else's childhood memories. And it's 50-50 those won't be as satisfying as yours.

You could try complementing your plastic masterpiece with tasteful natural evergreen arrangements. Indoor wreaths for, example, or a table centerpiece of pine branches, holly sprigs and berries, and fresh pine cones. Higher tech remedies include scented ornaments, infused oil scent makers to hide in the tree or other room odorants. Try Yankee Candle or even Home Depot, and of course there's a panoply of online offerings. Still time to ship in time for Christmas. Fair warning, some critics feel even the best synthetic remedies don't necessarily measure up to any of the real things. But you've got nothing more to lose. Dive in. Nose first.

We won't be going into the chemistry of baking pies and roasting fowl today, much less how to synthesize them odoriferously, but here are links to popular (and sometimes quite expensive) Christmas oils and seasonal candles on offer that are sure to upgrade your personal environment's aromatic appeal.

• 7 Essential Oils For An Amazing Aromatic Christmas Aromatherapy Lifestyles
  
  
• 45 Candles That Smell Like Everything You Love About Winter Elle

Just in case the tree is fake, the meal is take-out and bourbon and brandy don't do the trick for you. Yup, it's beginning to smell a lot like Christmas.